Strategies for Preventing and Managing Harmful Cyanobacterial Blooms

Technical/Regulatory Guidance

External Review June 2020

Prepared by The Interstate Technology & Regulatory Council Strategies for Preventing and Managing Harmful Cyanobacterial Blooms Team

NOTE

This page is a placeholder. The support contractor prepares

ABOUT ITRC

The Interstate Technology and Regulatory Council (ITRC) is a state-led coalition working to reduce barriers to the use of innovative environmental technologies and approaches so that compliance costs are reduced and cleanup efficacy is maximized. ITRC produces documents and training that broaden and deepen technical knowledge and expedite quality regulatory decision making while protecting human health and the environment. With private and public sector members from all 50 states and the District of Columbia, ITRC truly provides a national perspective. More information on ITRC is available at www.itrcweb.org. ITRC is a program of the Environmental Research Institute of the States (ERIS), a 501(c)(3) organization incorporated in the District of Columbia and managed by the Environmental Council of the States (ECOS). ECOS is the national, nonprofit, nonpartisan association representing the state and territorial environmental commissioners. Its mission is to serve as a champion for states; to provide a clearinghouse of information for state environmental commissioners; to promote coordination in environmental management; and to articulate state positions on environmental issues to Congress, federal agencies, and the public.

DISCLAIMER This material was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof and no official endorsement should be inferred.

The information provided in documents, training curricula, and other print or electronic materials created by the Interstate Technology and Regulatory Council (“ITRC” and such materials are referred to as “ITRC Materials”) is intended as a general reference to help regulators and others develop a consistent approach to their evaluation, regulatory approval, and deployment of environmental technologies. The information in ITRC Materials was formulated to be reliable and accurate. However, the information is provided "as is" and use of this information is at the users’ own risk.

ITRC Materials do not necessarily address all applicable health and safety risks and precautions with respect to particular materials, conditions, or procedures in specific applications of any technology. Consequently, ITRC recommends consulting applicable standards, laws, regulations, suppliers of materials, and safety data sheets for information concerning safety and health risks and precautions and compliance with then-applicable laws and regulations. ITRC, ERIS and ECOS shall not be liable in the event of any conflict between information in ITRC Materials and such laws, regulations, and/or other ordinances. The content in ITRC Materials may be revised or withdrawn at any time without prior notice.

ITRC, ERIS, and ECOS make no representations or warranties, express or implied, with respect to information in ITRC Materials and specifically disclaim all warranties to the fullest extent permitted by law (including, but not limited to, merchantability or fitness for a particular purpose). ITRC, ERIS, and ECOS will not accept liability for damages of any kind that result from acting upon or using this information.

ITRC, ERIS, and ECOS do not endorse or recommend the use of specific technology or technology provider through ITRC Materials. Reference to technologies, products, or services offered by other parties does not constitute a guarantee by ITRC, ERIS, and ECOS of the quality or value of those technologies, products, or services. Information in ITRC Materials is for general reference only; it should not be construed as definitive guidance for any specific site and is not a substitute for consultation with qualified professional advisors.

HCB-1

Strategies for Preventing and Managing Harmful Cyanobacterial Blooms

External Review June 2020

Prepared by

The Interstate Technology & Regulatory Council

Strategies for Preventing and Managing Harmful Cyanobacterial Blooms Team

1250 H Street, NW, Suite 850, Washington, DC 20005

Permission is granted to refer to or quote from this publication with the customary acknowledgment of the source. The suggested citation for this document is as follows:

ITRC (Interstate Technology & Regulatory Council). 2021. Strategies for Preventing and Managing Harmful Cyanobacterial Blooms. HCB-1. Washington, D.C.: Interstate Technology & Regulatory Council, Authoring Team. www.itrcweb.org.

ACKNOWLEDGMENTS The members of the Interstate Technology & Regulatory Council (ITRC) Strategies for Preventing and Managing Harmful Cyanobacterial Blooms Team wish to acknowledge the individuals, organizations, and agencies that contributed to Technology and Regulatory Guidance.

As part of the broader ITRC effort, the Strategies for Preventing and Managing Harmful Cyanobacterial Blooms Team effort is funded primarily by the US Environmental Protection Agency. Additional funding and support have been provided by the US Department of Defense, the US Department of Energy and the Lake Champlain Basin Program.

The Team also wishes to recognize the efforts of the following individuals:

Angela Shambaugh, Team Leader

Ben Holcomb, Team Leader

Jean Bradford, Writing Group Leader

Tony Ellanardo, Writing Group Leader

Kathy Coyne, Writing Group Leader

Steven Folsom, Writing Group Leader

Keith Pilgrim, Writing Group Leader

Michael Thomas, Writing Group Leader

Amelia Jones, Writing Group Leader

Kevin Sellner, Writing Group Leader

Rob Newby, Writing Group Leader

Beckye Stanton, Writing Group Leader

Brian Reese, Writing Group Leader

Christine Osborne, Writing Group Leader

[Add other appropriate acknowledgments such as: state regulatory representatives who developed the document, stakeholder participants, agency participants, industry participants, those who provided review and comment on the draft document, paid consultants/experts, etc.].

EXECUTIVE SUMMARY

Cyanobacteria are microscopic, photosynthetic organisms that can be found naturally in a wide range of freshwater aquatic systems. Under certain conditions, cyanobacteria can multiply and accumulate, to form harmful cyanobacteria blooms (HCBs). HCBs may produce potent toxins (cyanotoxins) that pose a threat to human health and their presence can also negatively impact animals, aquatic ecosystems and local economies by disrupting drinking water systems, recreation, commercial and recreational fishing, and property values.

In the academic and private sectors, development of solutions to address HCBs in water bodies have been long underway. Many of these solutions involve the implementation of technologies to prevent or manage HCBs by:

• reducing or removing nutrient loading to lakes, streams, rivers, reservoirs, ponds, and freshwater-influenced estuaries,

• managing active HCBs by physical or chemical controls,

• reducing the toxicity of cyanobacterial blooms, and

• improving wastewater and drinking water treatment technologies.

Because many of these technologies are emerging, proprietary, and span multiple scientific disciplines, water body managers are not well positioned to evaluate the efficacy of these technologies. Therefore, we developed this guidance document and associated web tools to provide criteria-based screening and third-party evaluation of the technologies’ peer-reviewed potential to prevent or manage HCBs.

Crucial to successful management of HCBs are structured, effective monitoring and communication programs. This guidance is also intended to help you select accompanying monitoring and communication approaches for cyanobacteria, nutrient reduction, or management technologies that are suitable for use in your water body based on water body characteristics, environmental triggers, and human activities. A wide range of options from rapid, physical response techniques to targeted prevention strategies provide water body managers with a variety of well-vetted technologies to address HCBs in a manner determined to be most appropriate for their community.

This guidance identifies a range of HCB monitoring, management, control, and prevention technologies relevant in the scientific community and environmental firms, and provides an independent evaluation, applicable to your water body through the filtering tools, to assess their potential implementation as a part of an integrated water resource management plan. As our understanding of cyanobacteria, cyanotoxins, and HCBs evolves, we recommend continued support for efforts focused on advancing innovative management of HCBs. The technologies and communication program components presented here were screened and narrowed down to be representative of successful approaches. All information presented in this guidance should undergo comprehensive, water body-specific assessment so that you may select the best strategies to protect your community and build support for implementation.

TABLE OF CONTENTS [The Table of Contents lists only section title and first-level subsection headings.]

EXECUTIVE SUMMARY ...... II 1 OVERVIEW ...... 1 1.1 Our Goals in Developing this Guidance ...... 1 2 USING THIS GUIDANCE FOR CYANOBACTERIA BLOOM RESPONSE ...... 3 3 INTRODUCTION...... 4 3.1 What are cyanobacteria? ...... 4 3.2 Health, environmental and economic impacts ...... 5 3.3 Cyanobacteria biological functions and environmental interactions ...... 12 3.4 Understanding Your Water Body and Developing a HCB Management Plan ...... 20 4 MONITORING ...... 22 4.1 Cyanobacteria Monitoring ...... 22 4.2 Developing a cyanobacteria monitoring program...... 22 4.3 Approaches to Monitoring ...... 25 4.4 Selecting Appropriate Sample Collection Methods for Your Lake’s HCB Event ...... 42 4.5 Water Quality Monitoring to Support Cyanobacteria Management ...... 48 4.6 Examples of Recreational and Drinking Water Monitoring Approaches for Cyanobacteria ...... 51 5 STRATEGIES FOR COMMUNICATION AND RESPONSE PLANNING FOR HARMFUL CYANOBACTERIAL BLOOMS ...... 51 5.1 Immediate Communication and Response Tasks ...... 57 5.2 Build, Improve and Maintain Response Capacity ...... 65 6 MANAGEMENT AND CONTROL STRATEGIES FOR HCBS ...... 75 6.1 Summary Table ...... 76 7 STRATEGIES FOR USE IN NUTRIENT MANAGEMENT ...... 79 7.1 Introduction ...... 80 7.2 Environmental Regulatory and Non-Regulatory/Voluntary Programs for Nutrient Control ...... 81 7.3 Public Education ...... 82 7.4 Source Identification and Prioritization ...... 83 7.5 Point and Nonpoint Sources of Nutrients ...... 85 7.6 Point Sources ...... 87 7.7 Nonpoint Sources ...... 102 8 RECOMMENDATIONS ...... 118 8.1 Overall understanding of cyanobacteria and cyanotoxins and their potential impacts ...... 118 8.2 HCB Monitoring ...... 119 8.3 Strategic Communication and Response Plans ...... 120

iii

8.4 HCB Management and Control Approaches ...... 121 8.5 HCB Prevention through Nutrient Reduction ...... 121 9 REFERENCES ...... 121

LIST OF TABLES

Table 3-1. Health impacts from various cyanobacteria, their toxins, and other compounds...... 6 Table 3-2. Compilation of HCB-specific economic impacts...... 9 Table 3-3. Reductions in property values from declining water clarity in multiple freshwater systems...... 10 Table 3-4. Role of water movement in planktonic cyanobacteria abundance and physiology. .... 17 Table 4-1. Monitoring methods used to identify and enumerate cyanobacteria...... 26 Table 4-2. Monitoring methods used to identify and measure cyanotoxins...... 38 Table 5-1. Summary of key HCB communication and response topics and tasks organized into two timeframes – immediate actions before or during a HCB and longer-term planning and continued collaboration beyond the immediate bloom season...... 52 Table 6-1. In-lake prevention and direct intervention strategies. The information summarized in the table below represents a typical, cost-effective application. For more specific information, strategies are hyperlinked to specific fact sheets...... 77 Table 7-1. Nutrient reduction strategy organization/selection based on source category and land use type...... 86

LIST OF FIGURES

Figure 1. High temperature selection of cyanobacteria relative to other common phytoplankton groups...... 16 Figure 2. Process and water quality conditions that influence one species of benthic cyanobacteria in flowing water (Phormidium)...... 18 Figure 3. Examples of planktonic cyanobacteria distribution in a water body...... 23 Figure 4. Common appearance and distribution of benthic cyanobacteria, which may be attached to substrate (A) or may break free as mats and float to the surface (B)...... 24 Figure 5. Common sequence of monitoring steps used to evaluate risk from cyanobacteria exposure...... 26 Figure 6. Using the jar test to assess the presence of planktonic cyanobacteria. Well mixed sample (A), settled material not likely to be cyanobacteria (B) and floating material likely to be cyanobacteria (C)...... 28 Figure 7. Using the stick test to assess the presence of cyanobacteria. Photos A and B show filamentous green algae, which has a hair-like appearance. Some benthic cyanobacteria may be picked up with a stick (Photos C and D) but do not look like hair...... 29 Figure 8. Using a microscope to identify cyanobacteria...... 32

Figure 9. Considerations in selecting HCB monitoring approaches. Physical sampling is discussed in the following sections. Remote sampling is discussed in section 4.3.1.3...... 43 Figure 10. Examples of several ways to collect grab samples for cyanobacteria...... 44 Figure 11. Phormidium in the Eel River. A/B-Micrographs of Phormidium cells (400x), C/D/E- Underwater photographs of Phormidium. F/G-Looking down on brown or orange patches of Phormidium mats in the river (blue thermometer is 15 cm long)...... 46 Figure 12. Two different rake samplers for benthic cyanobacteria...... 47 Figure 13. Secchi discs are a common tool used for measuring water transparency. Secchi measurements are often used to evaluate changes in phytoplankton, including cyanobacteria, over time. A- Clear water. B - Cyanobacteria bloom event...... 49 Figure 14. High frequency monitoring buoy deployed at Lake Hopatcong, New Jersey...... 50 Figure 15. New Jersey Department of Environmental Protection HCB response flow chart...... 55 Figure 16. Idaho HCB response flow chart...... 56

APPENDICES

Appendix A. A Visual Guide to Cyanobacteria

Appendix B. NALMS Survey on Risk Communication

Appendix C. Management and Control Strategy Sheets

Appendix D. Team Contacts

Appendix E. Glossary

Appendix F. Acronyms

v STRATEGIES FOR PREVENTING AND MANAGING HARMFUL CYANOBACTERIAL BLOOMS

1 OVERVIEW

Ponds, lakes, streams, and estuaries may take on unusual appearance and color – greens, reds, and browns are common – due to suspended algae or cyanobacteria. This document has been specifically developed to address accumulations of cyanobacteria because some species may produce toxins that are harmful to humans and animals.

Cyanobacteria are photosynthetic organisms that live in a wide range of aquatic and terrestrial systems environments. Many forms are microscopic and live in the water column or at the bottom of freshwater aquatic systems, such as lakes, reservoirs, and streams, so most of the time they go unnoticed. Cyanobacteria have an important role to play in aquatic ecosystems. They provide food and oxygen and also bring valuable nitrogen into the system. When environmental conditions become ideal (i.e. still waters, abundant sunlight, long days, high temperatures, and excess nutrients), cyanobacteria can grow, accumulate, and become extremely abundant. These dense populations are known as “blooms”.

Harmful cyanobacteria blooms (HCBs) may produce potent toxins, referred to as cyanotoxins. For this reason, they are a concern to human health, animals, aquatic ecosystems and the economy. HCBs can negatively impact drinking water systems, recreation, commercial and recreational fishing, and property values. These effects often mean that immediate response and communication are very important. In some cases, action to physically disrupt or remove the HCB might be appropriate. In others, natural decay and dispersal makes more sense. In all cases, potential for the release of cyanotoxins present inside the cells (intracellular toxins) into the water (extracellular toxins) must also be taken into consideration. Once the blooms subside, there is opportunity to consider how to reduce the magnitude, frequency, and extent of HCBs in the future.

1.1 Our Goals in Developing this Guidance

Many water resource plans now include prevention and management of cyanobacteria as a high priority. In this document, prevention is defined as proactive steps that you can take to make it more difficult for cyanobacteria to grow (e.g. nutrient reduction). Management is defined as a physical intervention in ongoing HCBs. Water body characteristics, environmental triggers, and human activities must all be considered to use prevention and management strategies successfully. Monitoring is key to identifying what supports HCB growth and evaluating whether your strategies have been successful. Consistent, informative, effective communication helps protect your community and builds supports for implementation of your resource plan.

This guidance is focused on strategies that you may use in response to cyanobacteria blooms that are found in freshwater aquatic environments, including lakes, streams, rivers, reservoirs, ponds, and freshwater-influenced estuaries. Furthermore, our guidance is intended to help you select monitoring, nutrient reduction, management, and communication approaches that may be suitable for use in your water body. We also recognize the need for rapid response, highlighting information and tools that are key when time is critical.

ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1.1.1 Introduction

Cyanobacteria are found in most aquatic ecosystems and may be present in terrestrial ones as well. The document introduction discusses the important roles cyanobacteria have in ecosystems and key aspects of cyanobacteria ecology that may be influenced by management approaches. We also present an overview of the human and animal health impacts that may be associated with exposure to cyanobacteria and share resources that will help you learn more about these topics.

1.1.2 HCB Monitoring

Data on cyanobacteria populations and the presence of cyanotoxins is needed to better understand current conditions and trends over time. We review common monitoring approaches and share additional resources that may be useful as you develop a cyanobacteria or cyanotoxin monitoring program. We have also developed a simple tool and metrics to help you decide which monitoring approaches may be suitable for your water body and monitoring budget.

1.1.3 Strategic Communication and Response Plans

How you respond to and communicate information about HCBs is important. Observations and results from testing or monitoring should be shared with your partners and the public in a uniform and consistent way. They should also be incorporated into broader actions at the local, state, and regional level for better overall communication about HCBs and potential HCB-related illness. We provide a framework to help you identify key partners, determine which tasks are important to do during HCB events and those that can wait, and build a strategic communication and response plan for HCBs. Examples of existing plans and communication approaches are shared throughout the chapter so you can see how other states and regions respond to HCBs.

1.1.4 HCB Management and Control Approaches

Ultimately, the goal of many lake management strategies is to prevent the occurrence of future blooms. There may also be times when management of active HCBs by physical or chemical control may appropriate. This chapter focuses on strategies for cyanobacteria management that are used in the water body itself. The number of potential approaches continues to increase and makes it difficult to choose one that may be successful in your water body. We review them based on peer-reviewed studies, history of use, cost, and how the technique works to control cyanobacteria. This information is shared in factsheet format for easy download. We also provide a tool that helps you compare strategies and select those that may make sense for your water body.

1.1.5 HCB Prevention through Nutrient Reduction

Water quality protection and restoration has focused on nutrients for decades. Limiting nutrients like phosphorus and nitrogen that serve as ‘food’ for cyanobacteria is key to reducing future HCBs. Land use activities are very important sources of nutrients that may eventually reach surface waters. We review common nutrient management approaches used in agriculture, forests, urban/suburban, and rural environments. Our summary graphic organizes nutrient management

2 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 approaches by land use sector and may help you identify areas that warrant investigation in the watershed surrounding your water body. We also point you to resources and examples of nutrient reduction strategies in use across the US and elsewhere.

1.1.6 Recommendations

Our understanding of cyanobacteria ecology, the production of cyanotoxins, and the triggers that encourage HCBs continues to evolve. There are many unanswered questions and a lot of research underway. New approaches to control HCBs in the water or catch nutrients flowing off the land are in development. As we developed our guidance document, information gaps and needs were recognized. We provide a series of recommendations that will inform and support future management of HCBs.

2 USING THIS GUIDANCE FOR CYANOBACTERIA BLOOM RESPONSE

This guidance document and the interactive selection tools provide the following information:

• basic, current information about the ecology of cyanobacteria

• a summary of monitoring approaches for HCB

• an outline of key elements of successful risk communication

• a summary of validated in-water body HCB management and control strategies

• a summary of key nutrient management strategies that help prevent HCBs

• suggested case studies, on-line resources, and other information that support the development of HCB prevention, management, and communication plans

This guidance does not replace current policy or regulatory standards. In addition, the guidance does not cover the following topics:

• state-specific permitting requirements

• detailed design criteria for individual site-specific use

• an exhaustive strategy selection

• verification or certification of strategy approaches

3 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

3 INTRODUCTION

3.1 What are cyanobacteria?

Cyanobacteria are prokaryotic organisms that are taxonomically classified as members of the Kingdom Bacteria (ITIS 2020). They are a normal component of water and bottom-dwelling biological communities. They are found in many aquatic and terrestrial systems.

Cyanobacteria are often lumped into a non-scientific category called ‘algae’ that includes organisms from a variety of taxonomic groups (Guiry 2019). Cyanobacteria blooms are also known as blue-green algae blooms or harmful algae blooms (HABs). In this document, we use the term ‘harmful cyanobacteria bloom’ (HCB) specifically to distinguish cyanobacteria from other potentially harmful algae populations in marine and freshwater habitats.

READ MORE START

Scientists have researched cyanobacteria and cyanotoxins for several decades, but overall understanding of their health-related impact to the human environment has advanced rapidly since 2000, and new, important findings are announced on a regular basis. Currently, the majority of research has focused on a single cyanotoxin (microcystin), and more specifically, on a subset of microcystin congeners (i.e., there are more than 200 known variations, or congeners, of the microcystin molecule) for test purposes. This focus on microcystin leaves significant gaps in the understanding of the ways other cyanotoxins affect people and animals. The body of research into the toxicity of the other cyanotoxins (anatoxin-a, beta-methylamino-L-alanine (BMAA), and others) is not as extensive as for microcystins and cylindrospermopsin, and USEPA and many states have not developed threshold values for these toxins. Individual states or jurisdictions may want to conduct additional literature review if the cyanobacteria taxa present in blooms produce these lesser-researched toxins to identify appropriate threshold values.

READ MORE START

USEPA and a number of state agencies have publicly available documents describing cyanobacteria and cyanotoxin monitoring in water bodies used for recreation and as drinking water sources, many of which can be found at USEPA’s Recommendations for Public Water Systems to Manage Cyanotoxins in Drinking Water (USEPA 2015g) and the USEPA’s list of state HCB monitoring programs. The USEPA Cyanotoxin Management Tools for Public Water Systems also offers tools for preparing a cyanotoxin management plan, treating and monitoring cyanotoxins, and communicating the risks.

The American Water Works Association and Water Research Foundation have developed a technical guidance manual for managing cyanotoxins in drinking water with a self-assessment tool for public water system operators to evaluate their risk and ability to handle a detection of cyanotoxins in finished water (AWWA/WRF 2015). Public water suppliers should consult with their state drinking water program to ensure the updated emergency response plan conforms to their state’s regulations and/or recommendations regarding HCBs. Public water system operators serving more than 3,300 people should update their emergency response plans to include a cyanotoxin event, consistent with requirements under the America's Water Infrastructure Act of 2018.

[READ MORE END]

5.2.5 Evaluate, Report, and Summarize HCB-related illness

It is important to evaluate information about individual illness cases during and after the bloom season. It may be helpful to review reports and articles of previous HCB-related human and animal illnesses (Backer et al. 2013, Backer et al. 2015, Hilborn et al. 2014). The agency or

68 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 poison control center tasked with collecting illness reports should draft procedures for internal tracking and/or submission to the OHHABS reporting system. Year-end summaries of the past year’s illness reports should be finalized, and any outstanding illness reports submitted to internal and/or OHHABS reporting systems.

It is important to ensure personal identification and privacy requirements are met when reporting aggregated illness information to stakeholders or the public. Aggregated reports by county and category (human, pets, livestock, fish, or wildlife) may be sufficient. It may also be helpful to include both the number of initial reports received and then the subset that meet the internal and/or OHHABS criteria for reporting illnesses as HCB-related. See California’s summary of OHHABS reporting.

Previous illness case information may also inform outreach to affected groups and locations. For example, nationwide concerns regarding dog illnesses in 2019 provided the opportunity to promote resources available for dog owners and veterinarians, including USEPA’s “Protect your pooch” page.

5.2.6 Develop, Evaluate, and Improve Outreach

Scientists throughout the US recognize that HCBs are a growing environmental and public health issue with far-reaching consequences. USEPA and many state agencies have prepared and distributed a wide variety of informational materials on HCBs. However, there are many ongoing and yearly opportunities for public outreach to inform people about the risks HCBs pose to their health and wellbeing. Agencies and other responsible entities can respond to ongoing blooms and prepare for upcoming bloom seasons by reviewing their outreach methods and materials and making adjustments as needed. A non-inclusive list of potential opportunities and examples is included below.

• Outreach events:

o Use Healthy and Safe Swimming Week information to help public health agencies inform the public about the health effects of exposure to HCBs. CDC has many Healthy and Safe Swimming Week resources.

o Outreach may also be timed to occur prior to major summer holidays, including 4th of July and Labor Day, when HCB are likely occurring and water recreation is high.

• Coordinated Responses:

o Develop official agency talking points and distribute them to anybody who may potentially respond to inquiries, including customer service staff, command center staff, spill hotline staff, and emergency management staff.

• Checklists for common questions/responses:

o Minnesota’s Blue-green algae and harmful algal blooms

69 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

o Virginia’s cyanobacteria page

o CDC’s FAQs on cyanobacteria and HCB-related health promotion materials including fact sheets, social media tools, posters, and reference cards that can be modified

o USEPA Health and Ecological Effects page

• Public outreach and social media messaging:

o Change out-of-office messages to let callers know how to find information/safety precautions on their own.

o Develop uniform social media messaging by working with all agencies that may be responding to HCBs.

o Create messages for topics such as early-season bloom awareness, mid-season bloom awareness or pre-holiday weekend messaging, boilerplate language that can be edited to respond to high profile events or media stories, and recommendations for dog safety during bloom and waterfowl seasons.

o Check out Toledo’s Water Quality’s FAQ for HCBs for an early-season drinking water example.

o Visit Wisconsin’s HCB toolkit, which includes easy-to-use guides that include general information about HCBs, health and safety information for people and pets, and communication tools.

o Review and evaluate past social media posts. Questions to consider when evaluating the effectiveness of social media posts include:

▪ Did the post get the response expected?

▪ Was there confusion? Which parts of the message created confusion?

▪ Did the message get derailed?

▪ Did the post reach the target audience?

▪ Was misinformation disseminated by other parties? If so, how could this information be effectively countered?

• Visual guides:

o Provide visual examples of blooms to help the public learn to identify potential HCBs for social media and outreach. For examples, see the Cyanobacteria Visual Guide or California’s quick visual guide factsheet.

70 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• Signage:

o Work with partners on developing consistent informational and advisory signage for bloom locations.

o Some states use a combination of educational (also referred to as general awareness) signage and advisory signage.

o Signs in multiple languages, particularly both English and Spanish, improve messaging.

o Examples include:

▪ USEPA has HCB infographics that can be customized

▪ Virginia Department of Health

▪ Wisconsin Department of Health Services

▪ Ohio Department of Health

▪ Utah Department of Environmental Quality

• Outreach to dog owners and veterinarians:

o Develop posters for dog owners and coordinate posting at veterinary clinics.

o Work with state veterinary boards to distribute information to practicing veterinarians.

o Develop a webpage and other outreach resources devoted to dogs and other animals, such as:

▪ CDC Animal Safety Alert Cyanobacteria blooms poster

▪ California HABs Portal domestic animal page

▪ Wisconsin Harmful Harmful Algal Bloom Toolkit

▪ Utah’s HABs pages on protecting dogs during blooms

• Outreach to fishing and hunting communities

o Nevada Department of Wildlife’s HCB page

o Utah’s advice for hunters

o California Waterfowl article on hunting dogs and HCBs

71 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• Conduct literature reviews to remain up-to-date on current information - the EPA Freshwater HABs Newsletter is an excellent place to start.

• Maps:

o Create maps that identify active blooms and any advisories in effect. Maps on dedicated HCB webpages provide visual/spatial snapshots of bloom conditions that support data and narratives and improve public understanding.

o Provide narratives and legends that clarify what the data represent. These can include caveats that all blooms in the state may not be represented on page/map, the map does not necessarily represent real-time data, bloom conditions in one area do not mean an entire water body is affected, and bloom locations can change rapidly due to wind and wave action.

• Surveys:

o Survey specific groups such as water body managers, public and/or environmental health department staff, and veterinarians to evaluate their needs for outreach materials.

o Other studies, including a survey done by the ITRC HCB Team and North American Lake Management Society (NALMS), indicated regional differences in preferences regarding HCB notification methods. The ITRC/NALMS survey on HCB notification methods provides information on regional HCB outreach/education efforts in a central location to help decision- makers identify the most effective HCB outreach/education methods going forward. See Appendix B [LINK to Appendix B] for more details and key findings.

• Communication on HCB management activities:

o Communicate updates and results once management strategies to control a HCB have begun.

o Communicate that some HCB management treatments may release toxins into the water column. Use signage and other communication methods to inform people of the lake’s status as changes occur, especially if the appearance of the lake improves while cyanotoxins may still be present.

o Communicate expectations, effectiveness and details about chemical treatment and management strategies before the activity begins.

72 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

5.2.7 Continue Coordination

5.2.7.1 Build and improve relationships with internal, external, and stakeholder contacts.

After bloom season concludes, it is important to continue building the network of people involved in an HCB response, such as local or state health departments, laboratories, public drinking water systems, state parks, lake managers, poison control centers, recreational water facilities, emergency preparedness and response agencies, physicians and veterinarians, local governments, and agriculture. Develop lists with key contacts (and their alternates) for time- critical notifications and ensure these contacts are entered into an incident report database. Refer to the USEPA for a list of health and environmental agencies by state for more information. Incorporate notification preferences as identified by the ITRC/NALMS notification survey [add link to appendix].

5.2.7.2 Organize Meetings and Workshops

Regular meetings and annual workshops can enhance internal and external coordination. Pre- season workshops for partners can provide an important forum to assess interagency coordination, review lessons learned about bloom response, identify areas for improvement, and exchange information to strengthen HCB responses. Workshops can include distribution of and training for test kit use. Additional suggestions include:

• Schedule monthly HCB-update meetings with partners to build and sustain working relationships and ensure ongoing communication between stakeholders.

• Develop a citizen science program to increase monitoring, testing, and coverage of water bodies. Many states provide opportunities for members of the public and watershed associations to measure and collect water quality parameter data following training in appropriate methods. Citizen scientists collect a wide array of water quality information across the country. For example, Vermont recruits and trains volunteer cyanobacteria monitors and lake water quality monitors.

• Participate in and facilitate trainings, workshops, webinars, and conferences at the local, state, and national level. USEPA’s freshwater HCB newsletter is a great source for upcoming HCB-related events. Along with a monthly newsletter, USEPA offers national and regional webinars and phone-meetings, allowing state agencies and other entities the opportunity to learn from each other and from academic researchers. To sign up for the newsletter send an email to [email protected].

• The national and regional chapters of the North American Lake Management Society provide resources and opportunities to collaborate on water body monitoring and management, including HCBs.

• If possible, offer free access to peer reviewed literature on HCBs.

73 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

5.2.8 Establish Agreements and Funding Sources

Establish operational memorandums of understanding or interagency agreements, as appropriate, to clarify roles and responsibilities, processes, and shared resources. Stable and consistent funding can allow for continuity of trained staff, sufficient resources, and well-developed response tools.

5.2.9 Optimize and Improve Data Management

Making HCB data available to the public is important for any HCB program. There are many ways to post data, including webpages, social media, online databases, GIS-based mapping programs, and standalone applications such as smartphone apps like the CyAN Project. Three examples:

• California Harmful Algal Blooms (HABs) Portal

• Washington State Toxic Algae website

• Utah Department of Environmental Quality Harmful Algal Blooms Home

Once the data have been posted for public consumption, consider long-term storage of the information. Multi-user databases with the ability to share information with other applications and the public can greatly increase the productivity of an HCB program. When possible, a team should be identified for developing a new database or a pathway to integrate the HCB data into an existing database. Data on HCBs and HCB-related illnesses may be able to be incorporated into existing public health tracking portals, such as Tracking California.

5.2.10 Develop and Refine Monitoring Plans for Recreational Waters and Drinking Water Sources

Comprehensive monitoring programs can become very expensive very quickly if the area monitored experiences frequent and widespread blooms. When designing a monitoring approach, it is important to consider how it will inform and support HCB management and response activities. It’s also helpful to perform post-action evaluation to improve future response and develop management and prevention recommendations. Monitoring programs serve an important role in HCB response as they can provide information on current conditions, variability across space and time, and insight into long-term changes at water bodies. Monitoring data generate critical information for public health responses and serve as educational resources for the general public. Blooms often appear rapidly and fade quickly, and it is not possible to capture every HCB that occurs. Instead, there is value in focusing on indicators that HCB are increasing, toxins are present, or that important uses such as beaches, drinking water, or wildlife are threatened. Long-term monitoring programs can provide insight into the frequency, extent and magnitude of HCBs. For technical details on monitoring options, see the Monitoring Section.

74 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

6 MANAGEMENT AND CONTROL STRATEGIES FOR HCBS

Resolution and prevention of cyanobacterial blooms and their potential toxicity is the ultimate goal of any Harmful Cyanobacterial Bloom (HCB) management strategy. However, this can be a daunting task given the large number of potential remediation technologies. The intent of this chapter is to consolidate and evaluate established and emerging treatment techniques currently being used to combat HCBs. The presentation of each strategy contains an assessment of the approach’s effectiveness, advantages, limitations, estimated relative cost, and information to help guide you to effectively implement the strategy in your water body.

Technology to treat, prevent, and manage HCBs is constantly evolving. The strategies presented in this chapter are not intended to be all encompassing. Nor is the goal to provide specific guidance for all water bodies and water body types; each water body is unique. This document does not provide endorsement for any specific technique. The information presented for each strategy represents the typical application scenario; there are additional scenarios that may not have been considered. Check with all required officials before implementing any management strategy. No treatment is guaranteed to provide total prevention or remediation. Blooms may return and, if improperly implemented, some management strategies can aggravate the situation or create harmful unintended consequences.

Any in-lake intervention strategy that employs the use of algaecides (e.g. peroxide, ozone, permanganate, or any product that kills cells) to manage an HCB event has the potential to create a scenario in which dissolved, toxic by-products are released into the water column. At elevated levels, these dissolved toxins can represent a threat to human health. This is a concern for drinking water treatment facilities. However, elevated levels of toxic by-products may overwhelm or complicate this process. Recreational water users can also be at risk if significant levels of toxins remain in the water after an in-lake HCB treatment. Therefore, all algaecides and coagulation compounds should be used at their minimum effective dosages and preferably in the early stages of HCB development. It is important to work closely with vendors and other experts while planning in-lake treatments. Monitoring for these toxic by-products is very important, particularly with respect to drinking water supplies and recreational-use water bodies.

In-lake treatment strategies can be categorized broadly as prevention or direct intervention approaches, with some strategies capable of being applied as both. The goal of prevention strategies is to prohibit cyanobacteria from dominating the natural community sometime later in a year and avoid future blooms. This is accomplished by controlling or manipulating conditions that favor cyanobacteria, or by the addition of compounds which may directly inhibit their growth and accumulation. Intervention strategies are used when a bloom has already begun and typically act directly on the cyanobacteria to reduce or remove them and sometimes their toxins (if present) from the system.

Treatments can also be grouped into their application type, whether they are chemical, mechanical, biological alterations, or some combination. Depending on the size of the water body and the bloom, some treatments can be deployed with little infrastructure. Other technologies require significant capital investment to implement or deploy, as well as annual maintenance costs, which can vary by scale of the deployment, region, and goals of the treatment.

75 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

If you wish to prevent future blooms by reducing inflowing nutrients from multiple land uses in a watershed, nutrient management strategies can be found in the Nutrient Reduction chapter. Strategies presented in the Nutrient Reduction section reduce the likelihood of HCB development downstream of the nutrient source. The strategies in this chapter solely considers strategies that are initiated within the water body or immediate shoreline area, broadly characterized as “in-lake” treatments. Note that this document uses imperial units (feet, acres) for large, linear, and spatial measurements and metric units (mg, L) for small mass and volume measurements.

6.1 Summary Table

HCBs pose serious threats to humans, domestic animals, and wildlife, as well as aesthetics for some water bodies. We have assembled a suite of in-lake strategies that can be considered for the prevention of future blooms or the reduction/elimination of an ongoing bloom, summarized in Table 6-1. This summary table presents information to help you select the most useful and practical approach for your water body of concern. Each management strategy entry summarizes the following information:

• Name of the technique

• Whether the approach is intended for prevention, intervention, or both

• Prevalence of documented history of use in the field and in research

• Relative cost ($, $$, $$$) per growing season to implement/maintain the strategy

• Maximum size of the water body that the strategy may be practically applied to

• A brief technical description of the strategy

For the purposes of characterization, working definitions for the following terms have been included as table notes and in the document glossary: prevention, intervention, substantial, limited, emerging, small, large, shallow, deep, lake/reservoir, pond, bay/estuary, and river.

To access more detailed fact sheets summarizing relevant information for potential implementation of each strategy you may:

• Follow the hyperlinked strategy in Table 6-1.

• Apply filtering criteria using our web tool [Link to tool when available] to refine the strategies best suited for the water body of concern.

76 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Table 6-1. In-lake prevention and direct intervention strategies. The information summarized in the table below represents a typical, cost-effective application. For more specific information, strategies are hyperlinked to specific fact sheets.

Cost per Management Management Supporting Water Body Growing Brief Technical Description Strategy Strategy Type Field Data Size Season

Shifting the pH out of the optimal growing range for cyanobacteria,

Acidification Prevention Limited $$ Unknown changing how well the cell is able to regulate its buoyancy and maintain its cell wall.

Placement of barley straw bales or Barley and rice Small bags in the shore zone of a water Prevention Substantial $ straw Lake/Reservoir body 1-1.5 months prior to expected bloom.

Indigenous bacteria are added to a Bacterial bio- Intervention & Small, Deep water body with a dense surface Emerging $-$$ manipulation Prevention Lake/Reservoir bloom of cyanobacteria using floating chambers.

Chlorine stock solution is added, Chlorine Small, Deep typically during the drinking water Intervention Limited $$ compounds Lake/Reservoir treatment process to disinfect and to reduce biological activity.

Mixing slightly acidified solution of Clay and Small clay and surfactant and dispersing surfactant Intervention Substantial $$-$$$ Lake/Reservoir over a bloom; sand may be added to flocculation cap the settled material.

Registered by the USEPA (but prohibited in some states from use) for controlling algae in water Copper Intervention & bodies. Copper algaecides interfere Substantial $-$$ Any compounds Prevention with the ability of algal cells to respire, photosynthesize and, at some concentrations, maintain cell integrity.

Physical removal of upper, nutrient- Small, Deep rich layer of bottom sediments to

Dredging Prevention Limited $$$ Lake/Reservoir reduce internal nutrient loads and limit cyanobacterial growth.

Floating Prevention Limited/ $$$ Small, Artificial islands planted with

wetlands Shallow various emergent plants, designed Substantial Lake/Reservo to absorb nutrients and support ir aquatic microbial communities attached to roots. Eventual

77 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

removal of plants reduces nutrient loading.

Flushing, Intervention Substantial $$-$$$ Deep Manipulation of in-lake hydraulics, and Lake/Reservo hydraulics by the pass through of

drawdown ir a large volume of water to control cyanobacterial growth and favor the growth of beneficial algae.

Mixers, Prevention Substantial $$$ Deep Designed to destratify a water aerators, and Lake/Reservo body or reduce limiting nutrient

diffusers ir concentrations in the hypolimnion to avoid exposure of nutrient-rich bottom waters into the epilimnion.

Monitored Intervention Substantial $ Any Permit HCB to decline naturally. natural Requires communication with

attenuation local users on threats and concerns and posting notices/signage.

Nano-bubbles Intervention & Emerging $$ Small Dispersal of 100 nm bubbles of Prevention Lake/Reservo air, oxygen, or ozone, to increase ir DO, oxidize organics, and/or kill cyanobacteria.

Nanoparticles Intervention Limited/ $-$$$ Unknown Iron-based nanoparticles used to

(Iron-based) adsorb HCBs and degrade Emerging cyanotoxins.

Organic Prevention Limited/E $-$$ Unknown Application of any of a diverse biocides merging group of biologically derived compounds (or synthetic analogs) that appear to have biocidal or bacteriostatic activity.

Ozonation Intervention Limited $$$ Unknown Infusion of ozone gas, a strong oxidizing agent, leading to a rapid breakdown of organic material.

Phosphorus- Prevention Substantial $$-$$$ Large Addition of lanthanum- binding Lake/Reservo substituted bentonite or

compounds ir aluminum-containing materials (e.g., alum) binds P to limit internal P sources.

Permanganate Intervention Limited $-$$ Small Acts as a total algaecide which Lake/Reservo may be effective against ir controlling cyanobacteria and their toxins.

78 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Peroxide Intervention Substantial $$ Small Application of granular or liquid Lake/Reservo peroxide compounds to HCB to ir levels approximating 3-7 mg/L kills cyanobacteria.

Shading with Prevention Limited $ Large Pond Application of colored dyes to

dyes reduce photosynthesis of algae and cyanobacteria.

Skimming and Intervention Limited $$ Unknown Physical removal of scum from

Harvesting buoyant HCBs.

Ultrasound Prevention Emerging $$-$$$ Small Transmitters propagate high- Lake/Reservo frequency pressure waves through ir the water column, which are thought to destroy gas vesicles of buoyant cyanobacteria.

Ultraviolet Intervention Limited $$$ Small, Advanced oxidation technique (UV) Shallow that works by passing water over

Exposure Lake/Reservo UV lamps resulting in the ir destruction of organisms’ DNA.

Notes: Intervention: an in-lake strategy that may be implemented to provide immediate relief for an ongoing bloom. Prevention: an in-lake strategy that may be implemented to decrease the likelihood or intensity of a future bloom. Substantial: multiple conclusive studies support this method. Limited: few conclusive studies support this method; or multiple inconclusive studies. Emerging: new area of research (post-2015). Small: less than 600 acres (Cael et al. 2017). Large: greater than 600 acres (Cael et al. 2017). Shallow: light penetration to the bottom, typically average depth of about 10 feet or less. Deep: experiences thermal stratification, typically depths greater than 10 feet.

Methods that are considered outdated or have only a very narrow range of applicability, as well as those that have only anecdotal support or endorsement from commercial providers, are not addressed in this document (see Appendix C for more information).

7 STRATEGIES FOR USE IN NUTRIENT MANAGEMENT

There are several structural and non-structural strategies in nutrient management which may be used to prevent the occurrence or reduce the magnitude, frequency, and extent of HCBs. Although nationwide guidance materials reviewed by the authors found no standard definition of “structural” vs. “non-structural” strategies, we are remaining consistent with standard practice on how various reduction measures are categorized by applying the following working definitions: Structural strategies in nutrient management typically incorporate unit treatment processes (and

79 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 could be either passive and natural or active and mechanical) such as sedimentation, filtration, adsorption, ion exchange, or disinfection. Non-structural strategies are generally programmatic in nature, such as education and outreach, regulation and enforcement, maintenance, and/or source control based.

The specific strategy chosen will depend on the planned or designated use and characteristics of the water body as well as the nutrient source. The Interactive Nutrient Management Graphic [Link to graphic when available] will assist a user in choosing appropriate strategies to use in a particular situation.

7.1 Introduction

Nutrients are important factors in the development of HCBs in aquatic ecosystems (Glibert and Burkholder 2006, Heisler et al. 2008, Smith, King, and Williams 2015). Nutrients can be carried to surface water bodies by several means, such as stormwater runoff, wastewater discharges (including residential septic systems), and agricultural practices. The most prominent source of nutrients will vary by location, making it important for water managers to understand the land use in the surrounding area.

Phosphorus may be one of the most important nutrients contributing to HCBs in freshwater systems, while nitrogen has been a key element in marine systems. Recent research however has suggested that nitrogen may be just as important as phosphorus in freshwater systems, with increases in both nutrients producing effects larger than the additive effect of each nutrient alone (Glibert and Burkholder 2006, Heisler et al. 2008, Paerl et al. 2019). Intracellular toxins, particularly nitrogen-rich toxins such as microcystin, tend to be lower when N is limited (Brandenburg et al. 2020). The forms and ratios of nutrients (e.g. organic, inorganic) may determine which genera and even species of cyanobacteria dominate, so nutrient reduction practices should consider both nutrients (Paerl and Otten 2016).

Irrespective of the specific relationship between phosphorus and nitrogen with HCBs, excess nutrient loading is directly linked to the formation of HCBs. Therefore, controlling nutrient entry into surface waters through best management practices (BMPs) is important for HCB prevention and reduction. In fact, nutrient reductions have successfully reduced bloom density and/or produced shifts in algal communities in some lakes where treatments have been implemented (Edmondson 1970, Paerl and Otten 2016, Lyon and Maxwell 1999, OECD 2003). Many nutrient reductions can be implemented through wastewater treatment upgrades, dredging, stormwater management, and changes in fertilizer use at large scales.

There are regulatory and non-regulatory options to consider when implementing nutrient control depending on the nutrient source. Further, public education and risk communication may help garner support and cooperation in strategy implementation and success.

Overall, water managers are encouraged to prioritize nutrient reduction by following these steps:

1. Check with regulatory agencies to determine whether key nutrient sources in a watershed have already been identified, and whether watershed plans or nutrient concentration

80 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

goals, such as total maximum daily loads (TMDLs) or site-specific criteria, have already been developed for the HCB-affected water body.

2. Develop actions that secure community cooperation such as outreach and education programs.

3. Gather existing data to characterize relative loading using models and/or monitoring, as necessary.

4. Identify predominant nutrient sources in the watershed. Leverage local knowledge, Geographical Information System (GIS) mapping, National pollution discharge elimination system (NPDES) databases, etc. if no previous assessment exists.

5. Prioritize efficient nutrient reduction strategies and the critical areas in the watershed where they should be installed.

6. Implement control strategies, emphasizing control of sources where most effective reduction is achievable.

While this document touches on all six elements above, its primary focus is on assessing control strategies. Here, we will explore these options and provide some recommendations about best practices.

7.2 Environmental Regulatory and Non-Regulatory/Voluntary Programs for Nutrient Control

In recent years, non-regulatory (i.e., voluntary) approaches to achieving environmental outcomes have been more favored than in the past (Lyon and Maxwell 1999, OECD 2003). The effectiveness of such programs is often not completely clear because of the numerous variables involved in an environmental outcome. Regulatory controls usually involve a system for tracking or reducing environmental discharges and reporting to an authority. Non-regulatory approaches often involve actions such as education, behavior change, or best practices modification and other practices that are not required by law. In general, a mixture of regulatory and non- regulatory approaches to mitigating environmental issues, including nutrient management and control, have been implemented in an attempt to reduce HCBs. A few of the measures pertaining to nutrient control to reduce HCBs are discussed below.

7.2.1 Regulatory Controls

Regulatory options involve permitting, monitoring, and reporting nutrient/pollutant discharges to help both the governing body and the water body manager better inventory and understand the amount of substance released and the potential impact on surface water.

7.2.1.1 Federal Controls: Clean Water Act

The 1972 Federal Clean Water Act (33 U.S.C § 1251) provides multiple ways to regulate nutrient entry into water bodies. The Clean Water Act (CWA) was designed to regulate discharges into surface waters from point sources, such as the end of pipes or constructed ditches

81 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

(USEPA 2016). Water quality standards include criteria used to calculate permit effluent limits, in addition to setting goals for TMDL restoration efforts. Section 319 of the CWA also provides a funding mechanism to incentivize implementation of nonpoint source watershed plans.

Point source pollution is controlled under the NPDES. Under NPDES, government agencies may issue permits to industry, municipal, or other organizations allowing release of pollutants from a specific site. The permit limits what a site can discharge and also contains monitoring and reporting requirements. USEPA delegates authority to conduct NPDES permitting to most states. More information about control of point source pollutants can be found in section 7.5.

READ MORE START

Watershed planning models, such as BASINS, SWAT, SPARROW, and Model My Watershed, allow for the estimation on how different conservation implementation scenarios across a watershed will affect downstream nutrient inputs. Implementation scenarios can include varying the BMP type, adoption rate, and whether the BMPs are targeted to high risk areas or installed randomly. The watershed planning models can be coupled with process-based models that estimate the algal and HCB response within a water body, such as WLEEM - Western Lake Erie Ecosystem Model (Verhamme et al. 2016), National Oceanic and Atmospheric Administration’s (NOAA) HAB Forecast, etc., to estimate the potential HCB reduction under certain scenarios. At the field scale, determining the correct BMP to minimize sediment and nutrient loss can be difficult due to a multitude of factors that affect BMP efficiency (e.g. soil type, slope, crop rotation, etc.). Some models, such as the Nutrient Tracking Tool, STEP-L, and Region 5, are able to estimate the effectiveness of BMPs at the field scale, which can help in the local managers determine the best BMP.

READ MORE STOP

For more information on models, the USEPA report titled “Nutrient and Sediment Estimation Tools for Watershed Protection” provides a detailed list of models and an explanation on the strengths of these various tools.

7.4.2 Nutrient Source Tracking

Nutrient source tracking (NST) uses state of the science forensic tools to identify sources of nutrients. It focuses on the most bioavailable forms of nutrients (e.g., nitrate and dissolved phosphorus), which are primarily responsible for algal growth and formation of HCBs. Tools used in NST include DNA markers to identify human waste sources, stable isotopes of nitrate and water, and advanced chemical indicators of sewage such as pharmaceuticals and personal care products (PPCPs). These advanced tools are often combined with traditional tools to locate and abate specific sources. Thus, NST can result in effective nutrient source control, often at a lower cost, by directly targeting and abating the most bioavailable nutrient sources. There are various approaches to nutrient source tracking that can be used in combination to build multiple lines of evidence to support nutrient source identification. These include:

• Isotopic analysis of nitrogen sources: Provides an indication of a broad range of sources of nitrogen within a water body. This method is useful if sources are not known.

• Measuring chemical indicators of wastewater: Identifies nutrients that are specific to human or livestock waste. This method can be used to identify and/or confirm wastewater sources.

84 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• Source-specific DNA markers: Identifies sources of nutrients that can be linked to human or animal sources. In contrast to chemical indicators, this method can identify nutrient contributions from waste of specific groups or species of animals.

• Adding tracers to source water: Used to confirm sources of nutrients. This method is most specific, as tracers must be added to the source of nutrients.

READ MORE START

Application Examples

In response to an algae TMDL in the Ventura River Watershed, Ventura County, California, where a nitrogen load allocation for approximately 3000 septic systems was assigned to a county environmental health department, nutrient source tracking was used as a strategy to refine this load allocation. Groundwater and surface water samples were collected downgradient of areas with varying septic densities and analyzed for nutrients, chemical sewage markers (pharmaceutical and personal care products), and nitrate isotopes. Results showed that groundwater nitrate concentrations were higher downgradient of areas with higher septic densities and chemical sewage markers and nitrate isotope results confirmed that septic effluent was a significant source. Surface waters were found to be affected where high density septic systems were impacting groundwater discharging to the stream, resulting in a narrowing of contributing septics to approximately 30% of the total septics in the watershed. These results are being used to help inform septic management actions including sewering of septic areas in the watershed and potential refinement of the septic load allocation in the TMDL. A summary of this project can be found in a report published by the California Stormwater Quality Association (Genkel, Ervin, and Steets 2019).

A similar nutrient source tracking study in the Atlanta Region showed that septic system density was correlated with nitrate concentrations in streams during dry weather and these results are also being used to inform septic management and policy in the region; a summary of this project can be found in a report published by Geosyntec Consultants (2019). These studies show how NST can be used to conclusively identify nutrient sources and support management actions to reduce loading from identified sources to surface waters.

READ MORE STOP

7.5 Point and Nonpoint Sources of Nutrients

Point sources and nonpoint sources refer to our ability to identify specific sources of nutrients and other pollutants to a body of water. These terms are defined more precisely in sections 7.6 and 7.7, but are categorized in Table 7-1 as related to specific land use types. Each of the point and nonpoint sources listed on the table are linked to a section of text below that more fully describes the source along with structural and non-structural strategies to mitigate or prevent nutrients from entering the water from each source. Regulatory considerations and examples are also provided for several of these sources of nutrients. It should be noted here that some sources of nutrients, such as stormwater runoff can be considered both point and nonpoint sources

85 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 depending on whether the stormwater is released into the body of water at a specific site, like a drainage pipe for example, or enters the water through diffuse flow.

Table 7-1. Nutrient reduction strategy organization/selection based on source category and land use type.

Land Use Type

Ag/ Lake Crop shore Land Forest Urban Suburban Source Category Description

Point Sources

NPDES permits establish discharge limits and conditions for discharges from municipal Municipal and Industrial wastewater treatment facilities x x x Wastewater Management to waters of the United States

Stormwater is rainwater or melted snow that runs off streets, lawns and other sites. When delivered to the water at a specific site such as through a drainage pipe, it can be x x x x x Stormwater Management considered a point source

Confined Animal Feeding Operations are agricultural facilities where many animals are raised, generating large amounts of manure and wastewater. Management of nutrients from these facilities component of nutrient reduction Confined Animal Feeding to reduce the incidence of x Operations cyanobacteria blooms

Nonpoint Sources

Runoff from agricultural land can be mitigated by best management practices, which Agriculture are intended to reduce the amount pollutants entering the x waterway.

x x Forestry Management Sources of pollution associated with forestry include removal of

86 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

streamside vegetation, road construction and use, timber harvesting, and mechanical preparation for the planting of trees.

Hydromodification/Habitat Hydromodification activities Alteration/Wetland/ include channelization and Riparian Areas channel modification, dams, and streambank and shoreline x x x x erosion.

Septic systems are underground wastewater treatment structures, Septic Systems commonly used in rural areas without centralized sewer x x x systems.

Management of stormwater Municipal and Rural Roads flowing off paved and unpaved Nutrient Management roads is important for the protection of downstream water x x x x quality.

Other Management Strategies for Nonpoint Source Nutrient Management Other less prominent nonpoint nutrient sources may exist x x x x within a watershed.

7.6 Point Sources

The term “point source” is defined in section 502(14) of the Clean Water Act as any discernable, confined and discrete conveyance, including but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from which pollutants are or may be discharged. This term does not include agricultural stormwater discharges and return flows from irrigated agriculture. Any source that does not meet this legal definition is classified as a nonpoint source.

7.6.1 Municipal and Industrial Wastewater Management

Wastewater carries considerable nutrients from human waste and industrial processes that can contribute to HCBs. Wastewater treatment can play a role in reducing the nutrients released and decreasing the extent, magnitude, and duration of HCBs. Currently, many wastewater treatment facilities in the US do not have nutrient permitting requirements. However, future regulatory requirements for nutrient reductions are likely for facilities upstream of water bodies with HCB problems and it is worth considering proactive point source nutrient reduction strategies.

87 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Wastewater treatment plants process water from homes and businesses. These waters may contain high levels of nitrogen and phosphorus from a variety of sources. Typically, wastewater treatment plants reduce nutrients to standards set and monitored by state and federal organizations before discharging to a water body. However, during times of high volume or heavy rainfall, wastewater treatment systems can operate less efficiently or overflow, releasing nutrients to the environment. Even when standards are met, wastewater can be a major source of nitrogen and phosphorus to a water body that contribute to HCBs.

Enhanced treatment systems enable wastewater plants to produce discharge that contains less nitrogen and phosphorus (USEPA 2019g). Sometimes appreciable nutrient reductions can be achieved with relatively inexpensive changes in plant operations (non-structural changes). In other circumstances, particularly those where changes to achieve very low nitrogen or phosphorus levels are required, expensive structural changes to treatment plant operations may be needed.

7.6.1.1 Non-structural Strategies

Industrial and municipal wastewater treatment plant operators can sometimes alter treatment processes to minimize the amount of nitrogen and phosphorus that is discharged to water bodies affected by HCBs. In other cases, operators can identify alternative discharge locations or otherwise modify the discharge schedule to reduce their load and minimize downstream HCB threats. It can also include policies, law and public education. Some examples are:

• Discharge Management

• Land Application

• Treatment Process Modifications

• Technology-based performance requirements

Lagoon discharge management provides an effective and non-energy intensive process for treating wastewater that utilizes ponds that are operate largely through environmental and biological means. Due to this, treatment process can depend on factors operators do not control such as temperature, wind, and light. Variable treatment outcomes can produce periods where excess nutrients can be discharged from lagoon ponds which can contribute to HCBs downstream of lagoon releases.

To combat excess nutrient loads, non-structural strategies that are commonly employed to regulate lagoon release include coagulation, flotation, land applications, and plant systems. Newer, experimental strategies being tested to remove nutrients from wastewater, such as absorption of nutrients with microalgae (Cai, Park, and Li 2013) or grasses on artificial floating islands in paper production wastewater (Ayres et al. 2019). These approaches can reduce the nutrient loading by removing sources of suspended solids and the associated particulate nutrient or by encouraging biological uptake of nutrients by plants and microbes.

88 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Alternatively, the risk of pond effluent to HCBs can be minimized by altering the discharge timing. Most lagoons discharge episodically and implementing controlled discharge to less sensitive periods for downstream waters affected by HCBs can be considered. Other modifications include separation of ponds with plastic curtains held in place by float and weighted anchors and more recent advancements that encourage growth and uptake of nutrients using floating mats of vegetation.

By their nature, processes in mechanical plants can sometimes be more easily altered to optimize nutrient removal (see for example the Nutrient Roadmap Primer). Treatment process modification can be conducted to encourage microbially-mediated removal by altering the amount of time that wastewater is exposed to aerobic and hypoxic environments. Chemicals can be introduced that change the alkalinity or amount of organic carbon in the wastewater to improve the efficiency on biological nutrient removal processes (USEPA 2015a). Another option is to add chemicals to induce precipitation of phosphorus (USEPA 2009).

Wastewater treatment plants differ extensively with respect to specific operational changes that could potentially be manipulated to reduce discharged nutrients. Optimization studies, including experimental manipulations, need to be conducted on a facility-by-facility basis. Once changes are recommended, plant operators will require additional training to implement them effectively. Given the added expenses involved, it is important to note that optimization processes are unlikely to be implemented without encouragement, via regulatory requirements or incentives, from regulators. However, with proper incentives considerable reductions are possible. For example, Montana recently conducted an on-site evaluation and operator training program and was successful in achieving and average reductions of 59% for nitrogen and 33% for phosphorus at a cost of less than $10,000 per facility.

Both lagoon and mechanical point sources can minimize their nutrient load by moving all or part of their discharge to surrounding lands. According to USEPA 2015a, land application is a broad term used to describe systems that discharge effluent (which may be primary, secondary or tertiary treated) into a natural soil system for additional treatment and dispersal into the receiving environment. Nutrient reduction from these processes can vary widely, sometimes becoming less effective over time if nutrient concentrations increase in the surrounding soils.

Water quality trading is a market-based approach to efficiently distribute and incentivize treatment upgrades or other approaches for reducing nutrient loads within the same watershed hydrologic unit code (HUC). This is based on the fact that some nutrients require implementation of costly control measures from one source, while measures to reduce the same nutrient at other sources are less expensive. Trading allows greater, but less costly nutrient reductions from one source to be transferred to another source where reductions may be more expensive in order to meet regulatory obligations. This flexibility allows for better outcomes at lower costs, capitalizing on cost differentials and economies of scale. In the United States, one of the objectives for water quality trading is to increase the speed for which reductions are implemented, as well as increase potential reductions through further technological advancements, for total daily maximum loads established under the CWA. Furthermore, these improvements may come at a cheaper overall cost of implementation and compliance, while improving the efforts and outcomes of environmental remediation.

89 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Further, water quality trading forgoes nutrient reduction for one source by utilizing improvements made by another source that exceeded required regulatory reductions. These reductions overall increase the efficiency of the system of environmental reductions, as it incentivizes polluters with the resources to make larger strides in pollutant reduction to do so. For more information on the advantages and disadvantages of water quality trading, see Three Strengths and Weaknesses of Water Quality Trading Policies (Fialko 2018).

More information about water quality trading options is available at Frequently Asked Questions about Water Quality Trading.

Pros. The advantages of these non-structural strategies can include:

• Reusable resources byproducts

• Reduced nutrient loading to enhance long-term water quality

• Can lead to improvements in community relations

• Reduced energy expenditures through optimization of aeration processes

• Monetary investment can be cheaper than other treatment alternatives.

• In the case of water quality trading, there can be substantial cost savings while achieving nutrient release reduction goals.

• Energy investment for operation is comparatively small versus other treatment alternatives

For more information about nonstructural wastewater treatment options that will reduce nutrient release, see the following sources:

• Wastewater Technology Fact Sheet – Facultative Lagoons

• Case Studies on Implementing Low-cost Modifications to Improve Nutrient Reductions at Wastewater Treatment Plants

Cons. While each of the strategies listed can be contribute to prevention of harmful cyanobacterial blooms, there can be some drawbacks to each as well.

• Lagoon discharge management

o Requires sufficient land

o Has a lower nutrient removal efficiency compared to other wastewater treatment approaches

o Nutrient removal can depend based on environmental conditions that can vary, such as temperature

90 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

o High ammonia loading under certain conditions although this can be remedied

• Treatment Process modification: Chemical

• Water Quality Trading

o Trading potential may depend on market conditions and available trading partners

o Trading must be restricted to avoid “hot spots,” or areas where discharges are high (Fialko 2018, MPCA 2019)

Regulatory or policy considerations. There are regulatory and policy considerations which should be considered when using these strategies.

Lagoon Discharge Management.

Requirements for lagoon discharges fall under local and national regulations for environmental quality. In the US the most common issue related to effluent is exceedance of total suspended solids. These suspended solids are often associated with cyanobacteria or other biological growth, rather than from fecal or other waste from influent. Upgrades to pond systems can be made to bring suspended solids and other nutrient loading down to the discharge limits proscribed by law.

Disinfection requirements can also change depending on the nature of land application being conducted. These requirements are often dependent on whether or not public can access the land and the type of crop irrigation being conducted. In the United States, these requirements differ on a state-by-state basis and the agency that oversees Clean Water Act implementation should be conducted to review potential land application options.

Water Quality Trading

In the United States, water quality trading must be consistent with the CWA. Generally, the USEPA supports reductions in nutrients and sediments, but will consider other pollutants on a case-by-case basis. Load allocations for each point source should be established based on total daily maximum loads, or in the case where a total daily maximum load has yet to be established, a baseline for the specific pollutant should be established based on performance requirements or other management practices developed from the necessary water quality standards.

More information

Principles of Design and Operations of Wastewater Treatment Pond Systems for Plant Operators, Engineers, and Managers (MDEQ 2015).

Application Examples

Lagoon Discharge Management

91 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

An examination of different lagoon designs was thoroughly reviewed by the USEPA in 2011 (USEPA 2011). Because of the number of variables involved in designing lagoons, specific case studies are unlikely to be relevant for each case. However, with the global popularity of lagoons as a wastewater treatment approach there is a large base of knowledge which can be accessed depending on the specific requirements of the lagoon requiring upgrades.

Treatment Process Modification

USEPA reports in its 2015 report that a wastewater treatment plant in Crewe, Virginia used lime for alkalinity control and also added molasses as an additional source of carbon. This process helped to enhance biological removal of phosphorus while also continuing at a steady rate of nitrogen removal. The average total phosphorus removal from the effluent was 0.06 mg/L. With aeration, the total nitrogen concentration dropped from 7.65 mg/l to 3.63 mg/l (USEPA 2015a, h).

Water Quality Trading

A 2005 review of water quality trading in the US identified 19 pollutant trading programs. Most of these systems had already established total daily maximum loads for the pollutant(s) being regulated, which included one or more of water flow, heavy metals, phosphorus, and nitrogen. The prices of implementing the trading programs and of operation varied between the projects. However, for the high costing programs, high implementation costs were found to be due to the level of detail required for an application, length of time for approval, and complications during negotiation. Operation costs were high due to monitoring costs, extensive application reviews, oversight, and inspection. In cases where trades did not occur, some of the many the reasons were down to not finding reasonable trading prices, tracking water quality changes, lack of stakeholder/polluter participation, and compliance issues.

Other considerations. Phosphorus is an important nutrient for plant growth, and experts have estimated that natural deposits will have been depleted within the next century. Capturing phosphorus from wastewater for beneficial use is an important strategy for sustainability, as well as in preventing HCBs.

7.6.1.2 Structural Strategies

Wastewater treatment plants can undergo upgrades that can reduce the number of nutrients discharged to surface waters, which can reduce the number of HCBs. However, structural changes to wastewater treatment plants can be expensive. There are changes to operations practices that can also help to reduce nutrient discharge that are lower cost than some of the structural changes. There are currently no standards for the most effective types of upgrades.

Some examples of structural strategies within a wastewater treatment plant, as stated by USEPA (USEPA 2015a) are:

• Aeration modifications, which work to create an anaerobic environment that supports denitrification.

92 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• Process modifications

• Configuration modifications

• Lagoon and other discharge modifications

For more information on these structure strategies and their effectiveness, see USEPA (2015a).

The USEPA is continuing to work to better understand what types of wastewater treatment is most effective, and currently has a study underway to access the most effective upgrades. See USEPA’s National Study of Nutrient Removal and Secondary Technologies for more information.

Pros. Some of the benefits that wastewater treatment plant structural improvements to reduce nutrient discharge are:

• Can reduce long term costs of water treatment plant operation

• Can produce reusable resources from waste products

• Reduce greenhouse gas and other air emission

• Reduces nutrient loading to enhance long-term water quality

• Can lead to improvements in community relations

• Accessible federal grants and/or loans for upgrading.

Cons. A few of the drawbacks of wastewater treatment plant structural improves are:

• Certain treatments or reactor types can involve complex implementation for successful operation

• Expensive up-front costs

• Does not removal all nitrogen and phosphorus

• Long-term durability of certain treatments and/or plants have not been well evaluated

Regulatory or policy considerations. Many legacy wastewater treatment plants release nutrients above the permissible limits of their host country. These permissible limits were designed in part to reduce eutrophication, and as HCBs and other water quality issues continue to receive further attention these upgrades may be become non-optional.

Application Examples.

A water treatment plant in Olbergen, Netherlands was discharging impermissible levels of nitrogen, phosphorus, and carbon/chemical oxygen demand (COD) due to waste coming from a

93 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 potato processing plan (Abma et al. 2010). The wastewater plant upgraded its treatment system to biologically convert excess carbon/COD into biogas (methane) while removing excess hydrogen sulfide, remove phosphorus from the water and precipitate the waste phosphorus so it could be recycled as fertilizer, and built a bioreactor to convert ammonia to nitrate. The generated biogas led to an extra annual 1.5 GWh of electric power, reduced total sludge production through the use of bioreactors, and saved €1.5 on discharge costs through decreased loading of nitrogen, phosphorus, and COD (Abma et al. 2010).

The Metropolitan Syracuse Wastewater Treatment Plant (“Metro”) in Syracuse, Onondaga County, NY is another example of a treatment plant where upgrades successfully reduced nutrient levels in the wastewater effluent. In 1998, Onondaga County signed an Amended Consent Judgement with the State of New York to decrease the ammonia and phosphorus discharges into Onondaga Lake. The Metro plant, whose treated effluent discharged into Onondaga Lake, was upgraded with the largest biological aerated filter system in North America and the largest tertiary ballasted settling system in the US. The biological aerated filter resulted in year-round nitrification (conversion of ammonia to nitrate) and contributed to the reduction of Metro ammonia loads from 522 metric tons/year between 1998 and 2003 to 82 metric tons/year between 2004 and 2007. The tertiary ballasted settling system, which came on-line in 2005, contributed to the Metro phosphorus load decreasing from 34 metric tons/year (annual average between 1998 and 2004) to 13 metric tons/year (annual average between 2004 and 2007), and ensured that the Metro effluent Total Phosphorus (TP) concentrations met the 0.12 mg/L limit in 2007 (OCDWEP 2009).

7.6.2 Stormwater Management

Stormwater is classified as a point source when it is discharged to a water body via piping or conveyances. Stormwater is regulated through the NPDES Stormwater Program. Control of stormwater with use of MS4 permits and control of industrial activities, construction activities, and CAFOs are methods to prevent HCBs. More information about control of nonpoint sources is presented in section 7.7.

Stormwater runoff can be a significant source of nutrients to urban watersheds. When stormwater flows over impermeable surfaces, it collects materials in its path, such as grass clippings, fertilizers, pesticides, animal waste, sewage, or other materials (Masoner et al. 2019, MPCA 2015a, USEPA 2019f). The nutrients that stormwater contains often depend on the surrounding land use.

Municipal stormwater can contain a variety of substances that could contribute to HCBs, such as fertilizers, sewage, and other solid wastes (USEPA 2019c). In a recent study of urban stormwater at 21 sites across 17 states, stormwater samples were found to have a median number of 73 organic chemicals. Phosphorus detections ranged from 4 to 788 µg/L with a median concentration of 92 µg/L (Masoner et al. 2019). Another study found that nutrient (especially phosphorus) concentrations in stormwater runoff were strongly related to road density and street canopy (Janke, Finlay, and Hobbie 2017).

Stormwater that flows from an industrial site could have a variety of substances, depending on the type of materials that are handled and produced at the site. Examples range from domestic

94 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 sewage to deicing chemicals to food processing waste. Stormwater that flows over a construction site might have sediment or chemicals from the site that could contain nutrients, while stormwater running through CAFOs could collect nutrients from animal waste.

Specific strategies to manage stormwater from each of these sources are available from USEPA’s NPDES Stormwater Program.

To help prevent HCBs, nutrients in stormwater need to be diverted from water bodies. This can be done through use of non-structural and structural BMPs.

7.6.2.1 Non-structural Strategies

Non-structural BMPs control nutrients in stormwater through policies and practices. Non- structural BMPs can be used by businesses or residents and involve site design strategies, stormwater pollution prevention plans, governmental regulations, or programmatic implementation of daily practices that will prevent materials from contacting stormwater. Education and training programs to raise worker or citizen awareness about protecting water bodies from stormwater are also potential elements of non-structural BMPs. Another type of non-structural BMP is undisturbed natural forest and wetlands (Horner et al 2002). Non- structural BMPs could be implemented at a site level, but could also be implemented at a community or regional level. More specific examples are described below.

READ MORE START

Restrictions on application of lawn fertilizers containing phosphorus and/nitrogen fertilizer restrictions have been put into place in several states, such as Minnesota (2002), New Jersey (2011), and Vermont (2011).

• Apply minimal amounts

• Use appropriate blends such as low P

• Apply once per year

See the following resources for more information:

• NJ Healthy Lawns Health Water

• MN Phosphorus Lawn Fertilizer Law

• VT Soil Fertility and Fertilization Guidelines for Lawn Turf

READ MORE STOP

Housekeeping. Housekeeping involves keeping work areas and sites orderly to prevent addition of nutrients or pollutants to stormwater that runs across the area.

• Pick up grass clippings

95 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• Use good spill prevention and response

Storage practices. Maintaining good storage practices will also reduce the addition of nutrients to stormwater:

• Store materials indoors

• Store materials in places unlikely to contact stormwater, or

• Cover materials with tarps

Control soil erosion on properties. Soil is an important source of nutrients, making control of erosion important.

• Leave vegetation in place when possible

• Prevent stormwater from flowing over disturbed soil areas

Outreach. Focused outreach or public education can be effective in controlling nutrients as well.

• Communicate with residents about good lawn maintenance

• Train grounds workers on good practices

At construction sites and industrial sites, non-structural BMPs for stormwater can also include:

• Controlling dust emissions

• Training employees on good practices to reduce stormwater runoff

• Installing water protective landscaping

• Aerating sites to avoid compaction from construction

Pros. Non-structural BMPs can be low-cost, easy to implement, and in some cases more effective than structural BMPs (Horner et al 2002) in preventing nutrients from entering water bodies. Non-structural BMPs that involve leaving natural areas in an undisturbed state have ecosystem benefits beyond HCB control (Horner et al 2002). Employee training, another type of non-structural BMP, is also part of good facility operations plan and may also meet other facility requirements, such as hazardous materials laws.

In the case of educational programs, (Pecher et al. 2019, Tonk et al. 2007)) report that increasing awareness among citizens might not directly affect water quality initially. They found only modest success in reducing stormwater pollution in commercial areas after conducting educational campaigns initially. However, over the long term, greater awareness may lead to “major and influential developments,” such as dedicated funding for stormwater management (Taylor and Wong 2002).

96 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Cons. As noted above, the non-structural BMPs are often dependent on changing human attitudes and behavior, such as cleaning up grass clippings and limiting fertilizer use. In addition, while setting aside areas of forest or wetlands to protect them from development has many positive effects, large areas may be required to achieve the benefit, which is often not feasible in urban areas. There can be tremendous pressure to use the land for other purposes, such as residential or retail development.

READ MORE START

In locations where deicing of roadways occurs, the deicing chemicals may run into stormwater BMP structures. The type of chemicals used and the likelihood of affecting water quality in a way that could lead to an HCB should be considered as well. For example, if chlorides reduce growth of vegetation around a BMP, the effectiveness of the BMP could decline. Further, deicers could raise the salinity of a water body. Some cyanobacteria can be more salt-tolerant that other freshwater species of algae, allowing more cyanobacteria to flourish (Pecher 2019, Tonk 2008).

New Hampshire has information on the Environmental, Health, and Economic Impacts of Road Salt at and Minnesota provides information on the environmental impacts of road salt and other de-icing chemicals.

READ MORE STOP

Regulatory or policy considerations. Several states and local governments have created policies on phosphorus in fertilizer. The effectiveness often depends on how aware community members are about the policies and the importance the importance with which they view the issue (Persaud et al. 2016).

Application Examples

An example of implementation of non-structural BMPs for nonpoint source is the Chesapeake Bay TMDL. After 25 years of little progress in improving the water quality of Chesapeake Bay, USEPA set out a more aggressive plan to control nutrient entry into the water. The Chesapeake Bay TMDL combines over 270 TMDLs from surrounding areas to create one TMDL. The area is using both point source strategies like wastewater treatment plant upgrades and nonpoint source BMPs, as well as policies on fertilizer use and other practices to improve the water quality. In 2018, USEPA reported a 60% decrease in the amount of phosphorus entering the Bay. USEPA also reports record acreage of underwater grasses after implementation of the strategies (USEPA 2018a). See the Chesapeake Bay TMDL for more information.

Another unique form of managing nutrient flow is being implemented by the state of Vermont where stormwater itself is being managed as a pollutant through a TMDL. Rapidly flowing stormwater can cause erosion and scour, contributing nutrients into a water body. Controlling the stormwater flow will help to increase infiltration. Read more about Vermont’s TMDLs at https://dec.vermont.gov/watershed/stormwater/impaired-waters/stormwater-tmdls.

97 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

7.6.2.2 Structural Strategies

Structural BMPs are physical constructed features that divert stormwater contaminants from surface water bodies. Structural BMPs are usually designed to slow stormwater rate of travel and allow for cleaning through filtering or settling and can help prevent HCBs by preventing nutrients from entering water bodies. Most of the features described below can be used for point or nonpoint sources, depending on the design and purpose.

Some examples include:

• Algal flow-ways (Algal Turf Scrubber): Algal flow ways, also known as “Algal Turf Scrubbers” are an engineered technology used to remove nutrients from a water body. The flow ways typically consist of screens with an attached algal community that are placed in a trough or raceway. Water is pumped over them and the algal community takes up nitrogen and phosphorus to incorporate into biomass that can be harvested for high value products such as biofuel. More information can be found at https://enst.umd.edu/research/research-centers/what-algal-turf-scrubber.

• Check dams: A check dam is a structure installed perpendicularly to the flow of a stream to slow down the water flow. This allows sediments and nutrients to settle out of the stormwater and reduces erosion. While this feature is often for nonpoint sources, it could also be used for point sources in some cases. See the Minnesota Stormwater Manual for more information on check dams for stormwater swales.

• Constructed embankments: Embankments are designed to capture and retain sediment in stormwater, reducing the nutrients that enter a body of water. See Sediment control practices - Sediment traps and basins in the Minnesota Stormwater Manual.

• Sedimentation systems: Like check dams and constructed embankments, sedimentation systems are designed to reduce the speed of water flow to allow nutrients to settle out before entering a water body. Some examples are sediment traps and sediment basins. Many more examples are listed in the USEPAs National Menu of Best Management Practices (BMPs) for Stormwater.

• Infiltration ponds and permeable pavement: Unlike systems designed to clean water before entering surface water bodies, infiltration ponds and permeable pavers allow stormwater to slowly infiltrate the soil, eventually returning the stormwater to groundwater. Nutrients and pollutants are removed from the water by the soil. See Infiltration basin in the Minnesota Stormwater Manual and Soak Up the Rain: Permeable Pavement from USEPA’s website.

• Phosphorus or nitrate capture systems

• Riparian buffers: According to the USEPA, riparian buffers are “vegetated zones adjacent to streams and wetlands that represent a best management practice (BMP) for controlling nitrogen entering water bodies.” Riparian buffers serve as a buffer around streams and water bodies, slowing entry of nutrients and other pollutants into the water. Riparian

98 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

buffers can be used for either point or nonpoint source control of nutrients depending on design. See Riparian Buffer Width, Vegetative Cover, and Nitrogen Removal Effectiveness (USEPA 2005b) for more information.

• Water harvesting for reuse

Please see the ITRC Stormwater Best Management Practices Performance Evaluation Chapter 3, BMP Screening Tool and Considerations for more information to consider on stormwater BMPs.

Pros. If non-structural BMPs fail to keep contaminants out of the stormwater, a structural BMP may help to prevent entry into a water body. Structural BMPs do not necessarily depend on human behavior and action (such as thoroughly cleaning up spills). They result in more immediate and measurable impact on water quality. In addition, structural BMPs can help lower flooding potential by slowing the water down or detaining it outside of the water bodies after a large rainfall.

Structural BMPs, like wetlands, rain gardens, or scenic ponds, might add aesthetic appeal or even add recreational opportunities to an area.

Cons. Structural BMPs require maintenance in order to maintain their effectiveness. Dredging, reconstruction, or inlet or outlet clearance might be required on a regular schedule (MPCA 2015b). BMPs with standing water, like stormwater ponds, may attract unwanted pests, like mosquitoes (Metzger 2008) or invasive weed species. They also can be a sink for trash and debris and pose physical dangers like a drowning hazard.

There may be high variability in the amount of nutrients both entering and exiting the system. The structural BMP installer should consider whether a BMP will be designed for typical runoff or to capture peak volumes. Extra steps, such as a way to establish and maintain a thermodynamic gradient, might be needed for dissolved phosphorus and adsorbed phosphorus (Rosenquist 2012).

Moreover, Small et al. (2018) found that even when volume of a nutrient, such as phosphorus, that enters a water body is decreased, a guarantee of reduced eutrophication is not assured. In a case study, preventing phosphorus from entering a lake by slowing the water prevented regular flushing of the lake. Warmer temperatures then induced release of phosphorus from the sediments, resulting in eutrophication (Small et al. 2018). Therefore, the selection of structural BMPs may need to be carefully evaluated for total impact on the lake systems.

Application Examples

Structural Stormwater BMP Performance. The ITRC Stormwater BMP Performance Evaluation Guidance provides an overview of the various performance data inventories available, including state technology verification programs (which focus primarily on proprietary devices) and the International Stormwater BMP Database (BMPDB) (which includes data for all BMP types).

The BMPDB is a publicly-accessible repository for stormwater BMP performance, design, and cost information. The overall purpose of the project is to provide scientifically sound information

99 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 to improve the design, selection, and performance of stormwater BMPs. The BMPDB is the largest known comprehensive database of stormwater BMP water quality performance study data that is regularly updated and maintained. Additionally, the BMPDB contains data from many parts of the United States, as well as several other countries. Continued population of the database and assessment of its data provides an improved understanding of the factors influencing BMP water quality performance and continue to help to promote improvements in BMP design, selection and implementation.

READ MORE START

The Water Research Foundation , a water quality focused non-profit research organization, is the current manager of the BMPDB project. As of November 2016, the BMPDB contains data sets from nearly 650 BMP studies that are accessible on the project website (www.bmpdatabase.org). The database contains searchable study data, web-based map interface, and a statistical analysis tool. The database can be used online or downloaded as a Microsoft Access file. Periodic statistical summary reports are also available from the website.

READ MORE STOP

ITRC has a guidance document specifically focused on stormwater BMPs. With this guidance, users are encouraged to select BMP types that are suitable for site-specific conditions and that are most effective for the bioavailable forms of nutrients that are controlling local HCB conditions. Other considerations should be weighed as well during BMP selection, including BMPs as sources of nutrients; for example, many vegetated BMPs include a vegetation support media that includes compost, which often exports nutrients into the BMP effluent. Be aware that for some BMP types, a statistically significant difference between influent and effluent concentrations may not be present. The effluent concentrations achieved by the BMP are relatively low and may be comparable to the performance of other BMPs that have statistically significant differences between inflow and outflow. For example, data sets that have low influent concentrations and similarly low effluent concentration (i.e., clean water in = clean water out) may not show statistically significant differences. However, this does not necessarily imply that the BMP would not have been effective at higher influent concentrations.

READ MORE START

This summary focuses solely on influent and effluent concentrations and does not characterize influent and effluent loads. For BMPs that provide significant volume reduction, load reductions may still occur in the absence of concentration reductions. Volume-related data can also be retrieved from the BMPDB and have been evaluated in detail for some BMP categories in reports posted at www.bmpdatabase.org.

READ MORE STOP

7.6.3 Confined Animal Feeding Operations (CAFOs)

Agricultural facilities where many animals are raised generate large amounts of manure and wastewater. Animals may be in open feed lots or confined inside structures and depending on the

100 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 number of animals present they may be considered animal feeding operations (AFOs) or concentrated animal feeding operations (CAFOs). CAFOs are considered point sources by the EPA and may be regulated under the National Pollution Discharge Elimination System (NPDES) if they have a discharge of pollutants to waters. Management of nutrients produced by AFOs and CAFOs is a priority in many parts of the country and also is an important component of nutrient reduction to reduce the incidence of cyanobacteria blooms.

Like other point sources, CAFO operations are regulated by NPDES regulations administered at the federal and state level (https://www.epa.gov/sites/production/files/2015- 08/documents/cafo_final_rule2008_comp.pdf). Facilities are defined by the number of animal units on site for farms raising cattle, dairy cows, sheep, pigs, horses, or poultry. Smaller farms may also be regulated as CAFOs if they have a point source discharge of waste and the regulating authorities identify them a significant contributor of pollution to a receiving water body. The regulatory definitions of large, medium, and small CAFOs can be found in the Code of Federal Regulations.

7.6.3.1 CAFO Management Strategies

With a few exceptions, most states have been authorized by EPA to identify and regulate CAFOs through a delegated state permitting program. Permit requirements may include a nutrient management plan and other documents that cover the:

• Management of manure, litter, and wastewater

• Proper management of mortalities

• Proper disposal of chemicals used at the facility

• Diversion of clean water away from the facility and strategies to keep animals out of surface waters

• Implementation of conservation practices and BMPs to protect water quality

• Protocols for testing of manures, wastewater, and soils

• Protocols for the land application of manure and wastes

• Documentation about how these elements were implemented

Permittees must provide annual reports describing their operations and renew their permit at regular intervals. Typically, inspections are required for permitted CAFOs however the frequency of these inspections may vary depending on their size and any state-specific requirements.

Management and permitting of concentrated animal facilities incorporates many of the strategies discussed elsewhere in this chapter for nonpoint agriculture. Large facilities in many parts of the

101 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 country operate storage lagoons and other wastewater management approaches that may store large volumes of manure and wastewater for several months at a time before being land applied.

Pros and Cons. While large scale animal operations may provide significant business efficiencies, the facilities, if not operated properly, can have a significant impact on local water quality. Operation of CAFOs have all the challenges of small scale agriculture – field based disposal of manure, soil erosion, and nonpoint source nutrient sources – as well as the challenges of managing significant amounts of manure and potential point source discharge from the production areas of the facilities if not well managed. Oversight of these entities through a single NPDES permit allows development of a coordinated water quality management plan for the entire operation, which may consist of several individual facilities or farms, and is potentially more efficient than having multiple smaller permits for specific aspects of operation. The sheer size of some CAFOs will continue to require new and novel approaches for management and disposal of potentially large quantities of manure to ensure the protection of downstream water quality.

Regulatory or policy considerations. Oversight of AFO facilities requires regular inspection and interaction with facility operators. States with regulatory authority over AFOs and CAFOs may choose to require additional measures beyond those outlined in the Clean Water Act. The amount of regulatory oversight of AFOs varies widely across the country.

Application Examples.

Vermont requires implementation of Required Agricultural Practices (RAPs) for all farms, including CAFOs and AFOs.

Iowa regulates AFOs – locations where animals are kept and fed for 45 days or more per year in a lot, yard, corral, building or other area – as confinements or feedlots. Both types include manure storage structures, but do not include livestock markets.

Colorado defines three types of animal operations - animal feeding operations (AFOs), concentrated animal feeding operations (CAFOs), and housed commercial swine feeding operations (HCSFOs).

7.7 Nonpoint Sources

As noted previously, any source that does not meet the legal definition of a point source is termed a nonpoint source. This includes any diffuse runoff that is not discharged through piping or conveyances (including stormwater), and any agricultural stormwater discharges and return flows from irrigated agriculture. This section discusses the dominant nonpoint sources and strategies to mitigate nonpoint nutrient discharge.

7.7.1 Agriculture

Agricultural Best Management Practices (BMPs) are intended to be practical, cost-effective actions that agricultural producers can take to conserve water and/or reduce the amount of pesticides, fertilizers, animal waste, and other pollutants entering our water resources. BMPs are

102 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 designed to benefit water quality and water conservation while maintaining or even enhancing agricultural production.

7.7.1.1 Non-structural Strategies

• Adopting Nutrient Management Techniques: Agricultural producers can improve nutrient management practices by applying nutrients (fertilizer and manure) in the proper amount, at the proper time of year, with an appropriate method, and with the correct placement.

• Monitoring: A significant element of verifying the efficacy of nutrient management techniques is the implementation of monitoring programs that provide a frame of reference to performance metrics.

• Recordkeeping: Memorializing nutrient management techniques and associated monitoring fortifies the management process and provides for continuous improvement.

• Engaging in Watershed Efforts: The collaboration of a wide range of people, stakeholders, and organizations across an entire watershed is vital to reducing nutrient pollution to our water and air. Agricultural producers can play an important leadership role in these efforts when they get involved and engage with their State governments, farm organizations, conservation groups, educational institutions, non-profit organizations, and community groups.

READ MORE START

United States Department of Agriculture’s (USDA) Natural Resources Conservation Council (NRCS) has recommended a 4R nutrient stewardship concept for nutrient management. The 4 Rs stand for Right Source (choose the right fertilizer product with the right nutrient ratio for the soil and crop needs), Right Rate (match fertilizer application rates with crop requirements), Right Time (synchronize nutrient availability with crop demand), and Right Place (place and keep nutrients where the crop can get to them and where nutrient use efficiency is maximized). Additional resources are also available from the North Central Region Water Network.

READ MORE STOP

Pros. Non-structural BMPs can offer a lower-cost alternative to structural BMPs, and often serve as a precursor to determine the appropriate practices to put into place.

Cons. The development of non-structural BMPs often requires attitudes to change towards reliance on consulting with outside entities to develop beneficial strategies for implementation. Without realization of an economic benefit, changing these attitudes may be complicated.

Regulatory or policy considerations. In the absence of specific local, state, or federal permitting requirements, agricultural producers can often utilize local agricultural extension agencies to provide assistance and guidance in the preparation of non-structural BMPs.

103 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

7.7.1.2 Structural Strategies

• Ensuring Year-Round Ground Cover: Agricultural producers can plant cover crops or perennial species to prevent periods of bare ground on farm fields when the soil (and the nutrients it contains) are most susceptible to erosion and loss into waterways.

• Planting Field Buffers: Agricultural producers can plant trees, shrubs, and grasses along the edges of fields; this is especially important for a field that borders water bodies. Planted buffers can help prevent nutrient loss from fields by absorbing or filtering out nutrients before they reach a water body. These buffers may serve as annual or perennial establishments to maximize their intended purpose and aligns with the agricultural producer’s goals in certain circumstances.

• Implementing Conservation Tillage: Agricultural producers can reduce how often and how intensely the fields are tilled. Doing so can help to reduce erosion, runoff, and soil compaction, and therefore the chance of nutrients reaching waterways.

• Managing Livestock Access to Streams: Agricultural producers can install fence along streams, rivers, and lakes, with an appropriate vegetated zone between the water body and the fence, to block access from animals to help restore stream banks and prevent excess nutrients from entering the water.

• Fallow Field Water Retention: During non-growing seasons and where applicable, fields can intentionally block water runoff and keep it on a field over the winter. This technique allows suspended particles to settle, keeping sediments and associated nutrients out of adjacent water bodies. No plowing and planting of a cover crop is required, and this is an additional cost-savings.

• Regenerative practices: Rotational grazing can maximize forage production by limiting livestock to defined portions of grazing areas, thereby reducing stress on other grazing areas to allow for natural reseeding, improving soil fertility, and reducing compaction.

Pros. Best Management Practices, when used appropriately, can mitigate the nutrient enrichment of neighboring water bodies which are the principal factors of eutrophication and Harmful Cyanobacteria Blooms. Importantly, the BMPs can aid in reduction of agricultural production costs through effective water and nutrient application rates as well as reduced erosion and soil loss; often more than offsetting the implementation costs. Certain BMPs for agricultural producers can be funded through federal/state/county cost-share programs.

Cons. BMP implementation costs are often an unanticipated capital expenditure for the agricultural producer. BMPs are often implemented on a field-by-field basis and change annually, making it difficult to track and to measure success. Moreover, the implementation of BMPs may not reach the targeted loading reduction of nutrients for all cases, resulting in additional measures to meet watershed management goals.

Regulatory or policy consideration. Some states have developed policy that associate implementation and maintenance of BMPs with a presumption of compliance with water-quality

104 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 standards for the pollutants addressed by the BMPs as a means to offset cost-prohibitive monitoring. Under certain circumstances, such as within watersheds that have developed Basin Management Action Plans for water quality improvements, the development and implementation of BMPs have become mandatory.

Application Examples

Agricultural Management Practices for Water Quality Protection

Ag BMP Success Stories

Other considerations. Certain agricultural practices, such as CAFOs, are designated by law as point sources. Nutrient management strategies at these facilities use BMPs addressing both point and nonpoint sources.

7.7.2 Forestry Management

Forested watersheds in general do not release large amounts of nutrients to surface waters and work to stabilize river flow and timing and volume of water reaching lakes, ponds, and reservoirs. Trees, both young and old, store nutrients within their trunk and roots. Perennial shrubs and annual plants also capture and retain nutrients. Undisturbed forest duff layers formed from composting leaves and branches protect underlying soils from erosion and release nutrients slowly over time.

Nutrients within healthy and well managed forested watersheds recycle within the forest itself and typically do not reach surface waters (Stone Environmental 2014). Water quality within healthy large forests is typically good. Smaller tracts can also provide important downstream water quality protection. Natural events such as landslides, windstorms, and heavy rain can create openings in forest cover that may release nutrients. Strategies outlined elsewhere may be of use to manage and reduce nutrients until these areas re-establish cover and natural recycling connections.

Activities in both managed woodlots and large tracts of forested lands typically disturb duff, expose soil, and otherwise facilitate the movement of sediment and nutrients to surface waters. Homes, businesses, and roads are found within large tracts of forested lands. BMPs specific to these land uses can be found elsewhere in this document. Strategies outlined below are designed to protect water quality in areas where forest harvesting and maintenance practices are underway.

7.7.2.1 Non-structural Strategies

Non-structural strategies for forestry management are broadly focused on working with landowners to understand forest ecosystems and raising awareness of the connection between forest activities and water quality impacts. Mechanisms to support and expand the use of best management practices through non-structural strategies include:

105 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• Conservation: Identify and preserve critical forested land and define healthy forest ecosystem services (clean water, climate control, recreational opportunities, etc.) in terms of their values to the community, particularly in areas experiencing rapid growth.

• Policy: Municipalities, states, and forestry organizations can articulate water quality goals and expectations for forest management through the creation of policy and forest management plans. State level forest policy, such as New Hampshire Forest Resource Strategies may establish consensus and strategies on how to conserve working forests, protect forests, and enhance forest resources for public benefit.

• Certification: Voluntary and mandatory certifications (e.g., sustainable) can be used to outline the goals of water-protective forestry approaches, review required practices and regulatory needs, and share best management practices that foresters can employ. Certification courses also can share cutting edge research and knowledge.

• Funding: Targeted funding programs, often through the USDA’s NRCS or state Extension offices, can pay for forest management plans that encourage the use of new strategies and improved forestry practices. Loans from state or federal agencies may be available to purchase equipment that is then shared or leased by foresters.

• Technical assistance: State and federal forestry staff can assist project managers in selection and implementation of best management practices.

• Forest Management Plans: Planning provides the mechanism to formulate short and long term goals to maintain forest biodiversity, balance forest uses and identify appropriate forest management practices, increases efficiency of management activities, and builds water- protective strategies into daily operations. Plans may also serve as communication tools between landowners, foresters, and local stakeholders.

• Public Education and Outreach: Targeted opportunities such as workshops and peer-to-peer training events can be highly effective in raising awareness about water and other forest resources, forest management plans, and preservation strategies, funding and experience with implementation of best practices. Federal, state, and local brochures and flyers serve to reinforce messaging.

• Forming Partnerships: Priorities for preserving forest resources can be implemented through partnerships among forest, land conservation, and water resources organizations to leverage resources and results.

Pros. Non-structural approaches can be very effective in delivering water quality goals in the forestry sector. Targeted policy and certifications set the standards for compliance. Funding and non-monetary assistance can encourage the adoption of strategies beyond basic compliance with regulations. Planning, education, and outreach reinforce policy goals and broaden public support for aspects of forestry management.

Cons. Policy and mandatory certifications may require a compliance, certification, and enforcement structure to be effective. Adequate funding requires a source of reliable revenue.

106 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Voluntary strategies may require significant outreach and education to gain acceptance. Stakeholder acceptance of some practices may take time to establish.

Regulatory or policy considerations. Forestry management impacts to water quality are considered nonpoint source and may have fewer state or federal regulatory oversight opportunities.

Application Examples. Examples of non-structural forestry management strategies supporting water quality nutrient management plans can be found in:

• Vermont’s Accepted Management Practices for Maintaining Water Quality of Logging Jobs;

• Forestry Best Management Practices - Mississippi and Wisconsin

• USEPA’s Watershed Academy module on Forestry Best Management Practices in Watersheds.

• USDA’s A Citizens’ Guide to National Forest Planning (2016) for guidance on forest management planning.

• US Forest Services’ Ecosystem Services Information

Other considerations. Areas experiencing rapid forest conversion near critical water resources should be prioritized for preservation and best management. More than 2,000 acres of forest land are cleared for development each day in the United States, and growth projections suggest that as many as 138 million acres of private forest land will be threatened by development between 2005 and 2030 (Stein et al. 2005). Data and mapping of forest conversion is often available from federal and state agencies, and non-governmental conservation and forestry organizations.

7.7.2.2 Structural Strategies

Structural strategies are water-protective approaches to be used in the forest environment during the active logging phase. Strategies may be voluntary or required. They are designed to minimize water quality impacts, such as sediment releases during logging and transport activities, protect existing stream corridors, and facilitate recovery of the site after active logging has ended. Structural strategies can also be used to maintain and support stream habitat. Examples include:

• The use of skidder bridges to protect stream crossings

• Proper construction of truck roads and skidder trails to prevent erosion

• Water bars to manage the flow of water across logging roads

• Construction of log landings to minimize erosion and soil compaction

• Containment areas for fuel used by on-site equipment and control of hazardous materials

107 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Pros. Forestry activities and logging may have significant impacts on water quality through erosion and sedimentation, release of fuels/hazardous substances, and increasing water temperature. Properly designed structural best management practices control or eliminate those impacts while improving efficiencies and minimizing over all costs, when considering the full cost associated with forest resource impacts. Water quality benefits of these approaches are easily measured.

Cons. Policy and mandatory structural requirements may require a compliance and enforcement structure to be effective. Structural strategies may require significant investment by foresters and may raise concerns about return on investment in poor market years (but see Vermont’s skidder bridge cost-share program).

Regulatory or policy considerations. State policy and mandatory participation may be necessary to achieve goals for structural strategies. Adoption of both mandatory and voluntary strategies might be facilitated by the availability of monetary support which requires reliable revenues.

• Application Examples. Examples of non-structural forestry management strategies supporting water quality nutrient management plans can be found in:

• Vermont’s Accepted Management Practices for Maintaining Water Quality of Logging Jobs

• Mississippi’s Forestry Best Management Practices

• USEPA’s Watershed Academy module on Forestry Best Management Practices in Watersheds

Other considerations. Funding to implement structural practices or equipment, such as funds allocated through USDA’s Healthy Forest Reserve Program or state programs, including drinking water source protection programs, may be available to fund structural practices that protect water quality and availability for public water supplies.

7.7.3 Hydromodification/Habitat Alteration/Wetlands/Riparian Areas

As defined on the USEPA website, hydromodification activities (USEPA 2016) include channelization, channel modification, dams, and streambank and shoreline erosion. In the context of nutrient management for HCBs, these activities can alter water temperature and the rates and paths of sediment erosion, transport and deposition. The channelization of streams and hardening of stream banks can increase the movement of nonpoint source pollutants within the watershed. Dams can negatively impact the temperature of the surface water they are influencing. Streambank and shoreline erosion can contribute increased levels of turbidity and nutrients to downstream waters (USEPA 2016, 2007).

As defined on the USEPA website, wetlands (USEPA 2018b) are areas where the water covers the soil or is present at or near the surface of the soil all year for varying periods of time during the year, including during the growing season. Wetlands also contain specially adapted plants (hydrophytes) and promote the development of wetland (hydric) soils (USEPA 2018b). In

108 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 addition, there is another similar regulatory definition of wetlands by the USACE and USEPA under Section 404 of the CWA.

Riparian areas are a natural buffer between upland areas and surface waters which may include wetlands, streams, and lakes. Both wetlands and riparian areas can act as natural filters of nonpoint source pollutants including nutrients to downstream water bodies (USEPA 2017a).

7.7.3.1 Non-structural Strategies

Nonstructural strategies for nutrient reduction related to hydromodification, habitat alteration as well as wetland and riparian areas are focused on the protection of water resources and land downstream from increased pollution.

Pros. These nonstructural methods are currently being implemented by local, state, and federal governments.

Cons. It is more difficult to measure success with nonstructural strategies. This may make these strategies less appealing as it is difficult to set concrete goals and benchmarks in terms of nutrient management.

Application Examples

The State of Maryland established the Shore Erosion Task Force which published recommendations to be implemented under a comprehensive Shore Erosion Control Plan.

The State of Virginia has the Chesapeake Bay Preservation Act which was established to protect and improve the water quality of the Chesapeake Bay, its tributaries, and other state waters. This act protects and preserves buffers in certain counties in Virginia (Virginia Department of Environmental Quality

The City of Atlanta, Georgia has buffer ordinances on streams and wetlands within the city.

The City of Seattle designates Riparian Management Areas (the land within 100 feet of a riparian watercourse) as environmentally critical areas.

The Vermont Agency of Natural Resources’ Rivers Program provides an opportunity for rivers to move with minimal damage to human infrastructure, corridor and floodplain protections. It also allows rivers to deposit phosphorus loads in their floodplains rather than in downstream lakes (https://dec.vermont.gov/watershed/rivers/river-corridor-and-floodplain-protection/river- corridor-planning-and-protectionhttps://dec.vermont.gov/watershed/rivers/river-corridor-and- floodplain-protection/river-corridor-planning-and-protection).

7.7.3.2 Structural Strategies

There are several structural strategies in terms of hydromodification, habitat alteration, wetlands, and riparian areas for nutrient reduction. The preservation, protection, and restoration of riparian areas and wetlands is a structural strategy (USEPA 2007). Both preserved and restored wetlands can act as particulate filters, nutrient sinks, and transformers of nutrients (Jordan et al. 2003).

109 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Vegetated riparian buffers are considered a BMP for nutrient reduction to surface waters (Mayer et al. 2007). In addition, planting trees and shrubs in riparian areas can reduce erosion as well as reduce the amount of sunlight and water temperatures, making the water body less optimal for algal growth (USEPA 2005b). The protection and restoration of streams and shorelines is another structural strategy (USEPA 2007). Stream restoration can include stabilizing stream banks, re- grading stream banks to restore a floodplain, installing riffle-pool complexes, or increasing sinuosity of a stream channel.

There are frequently local public education and advocacy groups that focus on the restoration and protection of surface waters. Many community groups aid in restoring riparian buffers by holding riparian buffer planting days.

Pros. Riparian buffer restoration can be an inexpensive way to reduce nutrients downstream and to protect surface waters from erosive stormwater. These areas can be replanted with trees, shrubs, or herbaceous vegetation that is generally locally available. If funds are not available, these areas can be preserved and allowed to re-vegetate on their own.

Cons. Wetland and stream restoration can be expensive in terms of materials and labor. Both of these restorative efforts generally require a team of experts to design and construct the restorations. In addition, these areas generally need to be monitored and often need to be maintained after construction.

Regulatory or policy considerations. Activities in surface waters including stream and wetland restoration are regulated by the US Army Corps of Engineers and often by the states. USEPA may also have the opportunity to comment on such projects. In addition, there are state and federal agencies such as US Fish and Wildlife Service (USFWS) that protect threatened and endangered species and other species of concern. These agencies will likely have the opportunity to comment on activities in wetlands and streams.

Riparian buffers are often regulated by localities, particularly in certain watersheds such as the Chesapeake Bay watershed.

Application Examples

“Restoration of wetlands from abandoned paddy fields for nutrient removal, and biological community and landscape diversity” focused on the restoration of abandoned rice paddy wetlands. It was found that these wetlands were efficient in the removal of nitrogen and phosphorus (Comín et al. 2001).

“Nutrient and Sediment Removal by a Restored Wetland Receiving Agricultural Runoff” focused on the removal of nutrients by a restored wetland receiving variable amounts of water from agricultural runoff. It was found that all the wetlands reduced nonpoint source pollution, but that variability of inflow could decrease the capacity of the wetland to remove nutrients (Jordan et al. 2003).

“Meta-Analysis of Nitrogen Removal in Riparian Buffers” focused on the removal of nitrogen by riparian buffers. It assessed characteristics of riparian buffers and how these characteristics

110 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

(buffer width, vegetation, etc.) influence the effectiveness of removing nitrogen (Mayer et al. 2007).

Other considerations. Stream restorations can be constructed to generate nutrient credits for stormwater in states like Virginia and North Carolina. These areas can also be important assets in water quality trading programs.

7.7.4 Septic Systems

More than one in five households in the United States depend upon individual onsite septic systems or small community cluster systems to treat their wastewater (USEPA 2005a). Septic systems treat wastewater in relatively small volumes (versus advanced centralized wastewater treatment plants) through both natural and technological processes, typically beginning with solids settling in a septic tank, and ending with wastewater treatment in the soil via a drain field. Septic systems include a wide range of individual and cluster treatment system designs that process household and commercial sewage.

Septic systems that are properly planned, designed, sited, installed, operated, and maintained can provide excellent wastewater treatment at reduced infrastructure, energy, and operating cost. The proper use of septic systems reduces the risk of disease transmission and human exposure to pathogens and positively affects water resources by recharging and replenishing groundwater aquifers.

Although septic systems may contribute a relatively small portion of total nutrient loads within a catchment, they can still represent a significant source of in-stream nutrients fueling HCBs, especially during periods when flow is low. In addition, it is estimated that 10-20% of septic systems are not adequately treating waste (USEPA 2005a). State water quality agencies identify septic systems as the second greatest threat to groundwater quality (USEPA 1998). Septic system failure results in contamination of surface and ground water with excess nutrients.

READ MORE START

Septic system failure can be attributed to three categories: design, operations, and maintenance.

• Design:

o Improper siting (shallow ground water, trees and vegetation, impermeable soils, springs, proximity to surface water bodies or drinking water wells)

o Inadequate sizing

o Local septic system density

o No absorption field in systems installed (pre-1970s)

o Inadequate construction (incorrect fittings, short-circuiting)

• Operations:

111 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

o Incorrect materials disposed in septic system

o Vehicles parked on absorption field or other activities that may damage the absorption field

• Maintenance:

o Periodic inspections not performed

o Pumping out of septic tank not conducted

o Loss of infiltration rate into absorption area and other age-related issues

READ MORE STOP

7.7.4.1 Non-structural Strategies

There are several options to address nutrient pollution prevention from septic systems in order to minimize risks of HCBs (NVPDC 1996). These fall into two categories: (1) non-structural BMPs to prevent failure of septic systems and (2) non-structural BMPs to minimize nutrient contamination from septic systems. State or municipal agencies provide guidance, policies, and regulations for the design, operation, and maintenance of septic systems (see US EPA Guidance, Policy and Regulations).

READ MORE START

Some watershed groups provide assistance for pumpouts and repairs of septic systems. The Bluegrass GreenSource in Kentucky used funding assistance through an USEPA grant to provide cost-share grants for repairs of free pumpouts for those who attended a workshop on how to maintain your septic system so that it functions to reduce harmful effects on water quality. This is just one example of how BMPs to prevent nutrient pollution can be achieved through homeowner outreach and education efforts.

READ MORE STOP

Pros. Non-structural strategies for septic system maintenance are relatively inexpensive and can be supported through homeowner outreach and education.

Cons. Reducing nutrient input to local water bodies through non-structural strategies can be a slow process, taking 10-20 years to see a significant response. This is due to a number of factors such as insufficient load reduction, low water exchange rate, and the release of “legacy” sources of phosphorus and other nutrients from sediments. In addition, septic systems are often grandfathered until they fail, and what constitutes a failure is often poorly defined.

Regulatory or policy considerations. In most states, maintenance of septic tanks is the responsibility of the building owner, and regulations often pertain instead to violations and necessary steps for remediation following septic system failure. Policy considerations can be specific to a region, and approaches to regulate septic system maintenance vary by municipality.

112 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Several case studies detailing steps taken by local governments are presented in Appendix E of this document.

Application Examples

Several case studies on increasing homeowner awareness are presented in this document (USEPA 2012).

Additional case studies highlighting successful outreach and education efforts can be found here.

A study conducted by Silverman (2005) showed that a door-to-door campaign to educate homeowners in northwest Ohio on proper maintenance of septic systems did not change management practices and suggests that more intrusive measures may need to be implemented to control pollution.

Four case studies are presented in Withers et al. (2012) detailed uncertainties in nutrient emissions from septic tanks in rural catchments of Europe and the UK.

Investigation of temporal variability in septic system discharges revealed seasonal impacts on nutrient pollution in streams (Richards et al. 2016).

Other considerations. Even with outreach and education, many homeowners do not think about their septic system until it fails. In the meantime, septic systems that are not properly maintained will continue to release pollutants to groundwater and may represent a significant source of nutrients to fuel HCBs. Studies show that the most successful non-structural strategies to reducing septic system failure include both education and support for the homeowner in conducting maintenance (USEPA 2012).

7.7.4.2 Structural Strategies

Structural BMPs for septic systems include considerations for siting, design, and installation of septic systems. Septic system technical Fact Sheets are available on the USEPA website and include several strategies to improve wastewater treatment and removal of pollutants.

READ MORE START

• Mound System: Enables the use of some sites that are unsuitable for in-ground systems. A more complete description is provided in Pipeline (National Small Flows Clearinghouse 1999)

• Effluent Screen: Enhances the removal of solids to prevent blockages that can damage the drain field.

• Leaching Chamber: Alternative to gravel drain fields that can extend the life of the drain field.

• Alternative Filters: Increases in loading rates may be achieved with crushed glass, recycled textiles, synthetic foam, and peat instead of sand.

113 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• Recirculating Sand Filters: Eliminate odors and increase oxygen content of effluent.

READ MORE STOP

Pros. Structural strategies to improve nutrient removal using septic tank systems are often complementary to non-structural strategies described above. They may be a more effective and proactive approach for reducing nutrients than maintenance alone. Many of the structural strategies listed above reduce the area needed compared to conventional septic systems or can be used in areas where conventional septic systems are not suitable.

Cons. Structural strategies for reducing nutrients in septic system effluent can be more costly to implement than non-structural strategies. Technical advances to septic systems may be more costly to construct and require more frequent routine maintenance compared to traditional septic systems. Extreme temperatures may need to be taken into consideration during design.

Regulatory or policy considerations. In most states, local health departments issue construction and operating permits to install septic systems under state laws that govern public health protection and abatement of public nuisances. Under most regulatory programs, the local permitting agency conducts a site assessment to determine whether the soils can provide adequate treatment to ensure that groundwater and surface water resources will not be threatened (https://www.epa.gov/septic/septic-systems-overview). A state-by-state list of septic system design and repair regulations in the US is provided by InspectAPedia.

READ MORE START

Inspection of septic systems are also required by some states upon sale of property. Iowa state law, for example, requires that septic systems must be inspected prior to the sale of a home or building and systems that are not adequate must be upgraded at the time of sale to meet minimum standards. Minnesota, on the other hand, requires that septic systems be inspected every three years, and that owners must disclose septic condition and compliance when selling or transferring property. In Delaware, property owners must have their system pumped out and inspected prior to completion of a sale, with some exceptions.

READ MORE STOP

Some states have incorporated water resource protection provisions to their septic system regulations because of the possible impacts from nitrogen and phosphorus. These provisions may include, but not be limited to, advanced treatment systems (aerobic systems or denitrifying drainfield media amendments to promote nutrient removal), prohibition of septic systems exceeding certain development densities, and inspection requirements as a condition of permitting.

Application Examples

Mounded drainfield design was investigated by (De and Toor 2017) showing that drip dispersal systems were most effective at reducing nitrogen and should be the preferred treatment approach in areas with shallow groundwater.

114 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Performance of recirculating sand filters was investigated in residential communities in CA and OR (USEPA 1999).

Crushed recycled glass was compared to sand by Gill et al. (2009). The glass performed similarly to sand in removal of nitrogen but was not effective at removing phosphorus. Addition of crushed glass to sand improved the rate and uniformity of percolation.

Other considerations. Structural strategies to enhance nutrient removal by septic systems should be carefully considered during new construction when implementation of many of the technical advances discussed here would be most cost-effective.

7.7.5 Suburban and Rural Road Nutrient Management

In general, road management and maintenance practices facilitate the movement of water off the road surface as quickly as possible to maintain safe driving conditions. The management of stormwater flowing off paved and unpaved roads, as well as from roadsides, is important for the protection of downstream water quality. This section discusses diffuse stormwater discharge; stormwater discharge through pipes or conveyances is regulated as a point source and was discussed in earlier sections. In the context of HCBs, stormwater from roads can be a significant contributor of nutrients and sediments to receiving waters. Surface materials from unpaved roads can wash off during storm events and high flows from both paved and unpaved roads can cause erosion of adjacent roadsides. Stormwater management from roads that are hydrologically connected (run adjacent to or cross water bodies) is particularly important. Strategies discussed in this section are focused on suburban and rural roads where space is typically of less concern than in the urban environment, allowing for management options that may not be feasible in more developed areas. As noted previously, stormwater from urban roads are managed as point sources through MS4 permits, and corresponding nutrient control was discussed previously.

7.7.5.1 Structural and Non-structural Strategies

Non-structural approaches focus on raising awareness about the water quality impacts caused by stormwater flowing from roads, designing new roads to have the lowest feasible water quality impacts, and updating maintenance practices to reduce water quality impacts. Installation and repair activities can be planned in advance, allowing identification of the appropriate approach and efficient management of equipment and staff. Non-structural approaches can also include the development of policy or legislation, permit requirements, and training opportunities.

There are many structural road BMPs designed to reduce erosion and minimize the movement of nutrients into adjacent waters. Generally, they promote getting water off the road quickly; stabilize and vegetate roadsides including adjacent ditches and stormwater structures (culverts, inlets, outlets, etc.); divert runoff to vegetated areas where pollutants and nutrients can be captured in the soil; maintain natural buffers and drainageways; minimize the creation of steep slopes; and maintain as much of the adjacent natural vegetation as possible.

Pros. Training and outreach around stormwater management from roads helps municipalities and road crews recognize locations and situations where surface waters may be impacted by nutrient- rich sediment and run-off. Planning for new roads and repairs of existing roads can then utilize

115 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 the best available management strategies applicable to local conditions. Education and outreach opportunities can utilize experienced local road crew staff as mentors and trainers. Hearing about the successful use of new BMP practices from peers increases acceptance and usage by other road managers.

State policy, regulations, and permitting may facilitate rapid adoption of stormwater rules across the entire state simultaneously. Funding opportunities can facilitate compliance and early adoption of the new requirements. With the large array of BMPs available for consideration, municipalities and responsible parties can develop road management plans to fit specific needs and budgets.

Cons. Not all states have mandatory stormwater management requirements for the construction of new roads or improvement of existing systems in the rural and suburban environment. Voluntary strategies may not gain widespread adoption due to cost and lack of available land to house BMPs. For existing roads, the cost of upgrades to meet water quality goals may be significant. Without dedicated funding to support implementation of strategies identified during training and prioritization exercises, road improvements may be delayed or never take place. BMPs must be adequately sized to accommodate increasing stormwater volumes expected with climate change, increasing cost.

Regulatory or policy considerations. Policy and regulation may be required to support widespread adoption of road management BMPs. Funding and other support structures (e.g. training and certifications) typically are necessary to support adoption.

Application Examples

Examples of non-structural strategies for road design and maintenance include

• Connecticut: Highway Stormwater Products

• Vermont: Municipal Roads General Permit requires communities to complete a Road Stormwater Management Plan by the end of 2020 and provides a suite of technical assistance and funding to facilitate compliance including the Road Erosion Inventory and the Better Roads Program.

• Washington Department of Transportation Municipal Stormwater Permit

Examples of structural approaches can be found in:

• Maryland – Structural Stormwater Controls

• Nebraska – Drainage Design and Erosion Control Manual

• Vermont – Better Roads Manual

Washington – Highway Runoff Manual

116 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

7.7.6 Other Management Strategies for Nonpoint Source Nutrient Management

Other less prominent nonpoint nutrient sources may exist within your watershed. Any location which has been developed or otherwise altered from its natural state could contribute or convey nutrients to surface waters. Roadside and agricultural ditches, resource extraction, marinas and boating facilities, developed lots in otherwise forested watersheds, and lakeshore development are all examples of areas that may be locally important sources of nutrients.

7.7.6.1 Non-structural Strategies

Since these sources are frequently localized and small scale, education and outreach campaigns are often the primary non-structural strategies. Policy and regulations may be appropriate where a single type of nonpoint source nutrient loading is abundant (e.g. low density development around lakeshores) or may be a concentrated disturbance (e.g. gold dredging in streams).

Pros. Small or scattered nutrient sources can be important drivers of HCBs, particularly for smaller water bodies. On larger water bodies, the cumulative effects of these small sources may be significant. To successfully reduce the occurrence of HCBs in low nutrient lakes, management of these smaller sources is often as important as the management of larger ones.

Cons. Management of these smaller sources is often voluntary or difficult to enforce. Homeowners are typically most directly affected and may not recognize the importance of managing their small nutrient contributions. It can be difficult to implement a permitting or regulatory program for smaller and less abundant nutrient sources.

Regulatory or policy considerations. Often policy, statute, and regulations are necessary to address these smaller sources. Without strategic and frequent reinforcement of messaging around the importance of these small nutrient sources, it can be difficult to get the stakeholder support necessary to create policy and regulations.

Application Examples. Many states have addressed smaller nutrient sources through voluntary and required approaches:

• Lakeshore regulations for new development – Maine, Minnesota,, and Vermont

• Voluntary Lakeshore guidance – Maine’s Lake Smart, Minnesota’s Restore Your Shore, and Vermont’s Lake Wise

• Boating Pump out requirements – New York’s regulations

• Resource extraction

• Green infrastructure – Illinois’ Green Infrastructure Plan

7.7.6.2 Structural Strategies

Structural BMPs for smaller or localized sources often focus on reducing the amount of impervious surface and directing stormwater away from surface waters. These approaches

117 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 decrease the overall volume of water and the cumulative nutrient load it delivers. Reducing flow also controls the physical erosion of ditches and streambeds receiving stormwater. Redirecting nutrient-laden stormwater onto vegetated areas allows water to infiltrate the soil, removing contaminants and supporting groundwater recharge.

Pros. Many of these small structural approaches are inexpensive to include when planning new development or can be retroactively applied on the landscape. They can be combined to create an overall stormwater management approach over a larger area.

Cons. The smaller scale of these BMPs can make them seem less important when compared to larger sources within the watershed. Application of these smaller scale projects is often voluntary. Maintenance of these smaller structural BMPs, critical for continued effectiveness, is often neglected.

Regulatory or policy considerations. Design and construction requirements for small scale structural BMPs may vary by state. Check with your state agencies regarding permits. In some arid areas of the United States, stormwater management intersects with water rights management and BMPS utilized elsewhere may not be allowed.

Application Examples. Check your state’s stormwater management entities for more information on managing small nutrient sources

• Slow it, sink it, spread it – green stormwater infrastructure guidance, Santa Cruz CA

• Vermont’s Guide to Stormwater Management for Home Owners and Small Businesses

• Connecticut’s Guidebook for Marina Owners and Operators for the Installation and Operation of Sewage Pumpout and Dumping Stations

• Alaska’s Clean Harbors Certification program

• USEPA’s Green Infrastructure website

8 RECOMMENDATIONS

Through this process, the HCB team identified information gaps and research needs related to HCBs. In this section, we provide a series of recommendations that will inform and support future monitoring, response, management, and prevention of HCBs, which are included below by the corresponding section.

8.1 Overall understanding of cyanobacteria and cyanotoxins and their potential impacts

One overarching recommendation is for all involved in the HCB community to develop and use a common language for cyanobacteria and HCBs. The common language should be applied to identifying cyanobacteria, describing prevalence or abundance of cyanobacteria, defining events of concern, and taking protective actions.

118 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

8.1.1 Health Impacts

• Develop a greater understanding of fish and plant tissue accumulation of cyanotoxins (such as by species or trophic level) and predictors based on water concentrations (may be water body type specific).

• Continue to research the impacts of cyanobacteria and cyanotoxins on human health

• Explore potential toxicities of cyanopeptides and threats to human health.

• Continue to characterize and assess the impacts of cyanobacteria and cyanotoxins on water distributed from drinking water facilities.

8.1.2 Cyanobacteria Ecology and Environmental Interactions (links to 3.3.1.2)

• Continue to research triggers stimulating the production of cyanotoxins.

• Continue to research the role of nitrogen and the management of HCBs in the freshwater environment.

• Continue to research the environmental and physiological triggers stimulating the growth of benthic cyanobacteria. Also important is research into the triggers for cyanotoxin production in this habitat.

8.1.3 HCB Management Plan

• Develop and distribute a standardized flexible/revisable guidance document that instructs managers on what should be identified as characteristics of the water body and incoming waters, land use in the watershed, and engagement options for residents, organizations, and others.

8.2 HCB Monitoring

8.2.1 Remote Sensing

• Expand the number of water bodies which can be evaluated using remote sensing for HCBs by developing and providing access to smaller spatial scale data and products

8.2.2 Pigments

• Explore the development of regionally based phycocyanin concentrations to support rapid assessment of HCB conditions in recreational settings.

8.2.3 Cyanotoxin Testing

Expand cyanotoxin testing to include:

• a greater range of the potential variants for each cyanotoxin class

119 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• capacity to run more cyanotoxins simultaneously with reduced overall turn-around time

• “unknown” or less studied toxins, such as cyanopeptides and guanitoxin/anatoxin-a(s)

• standardized methods for tissue cyanotoxins (including covalently bound toxin) for fish, wildlife and plants

• standardized methods and commercially available tests for cyanotoxins in human samples, such as serum and urine

8.2.4 Sampling for Cyanotoxins

• Expand access to standardized sampling methods for air monitoring for aerosols that potentially contain cyanobacteria and cyanotoxins to help in establishing a greater understanding of this component of potential exposure.

8.2.5 HCB data management

• Develop a standardized format to manage HCB-related data

8.3 Strategic Communication and Response Plans

• Develop and use a common language related to cyanobacteria and HCBs.

8.3.1 HCB Advisory Thresholds

• Conduct a critical assessment of toxicities of all potential cyanotoxins and cyanopeptides in drinking water and disseminate the results.

• Conduct further research on toxicity of guanitoxin/anatoxin-a(s) and establish health thresholds.

8.3.2 Drinking Water Supply Emergency Response Plans

• Adopt recommended drinking water facility infrastructure and treatment methods to address all potential cyanotoxins and cyanopeptides on a national basis.

8.3.3 Outreach

• Incorporate unique messaging to address benthic cyanobacteria, including potential occurrence with clear water and in mixed assemblages with non-toxic filamentous algae and diatoms, in outreach materials.

8.3.4 Monitoring Plans

• Identify effective monitoring plans across a suite of water body types and provide as a consolidated resource of examples for local managers and officials.

120 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• Address future climate in monitoring plans, including higher temperatures and boom-bust precipitation patterns (major storms separated by longer droughts).

• Address explicitly the potential for benthic cyanobacteria in monitoring plans, including the specific sampling methods that may be needed depending on water body type.

8.4 HCB Management and Control Approaches

• Conduct and disseminate scientific investigations on emerging methods for controlling HCBs.

• Document both successes and failures with HCB treatment technologies in the scientific literature.

• Assess effectiveness of emerging mitigation and control strategies on an ongoing basis and distribute the assessment results.

• Document potential costs for implementing and operating treatments in future efficacy assessments.

8.5 HCB Prevention through Nutrient Reduction

• Identify effective nutrient reduction practices that successfully reduce the frequency, magnitude, or toxicity of cyanobacteria populations, likely associated with specific land uses and receiving water characteristics.

• Rigorously monitor the efficiency and success of nutrient management best management practices, including long-term maintenance requirements and changes in effectiveness over time.

• Document both successes and failures with nutrient management practices in the scientific literature.

9 REFERENCES

Abma, W. R., W. Driessen, R. Haarhuis, and M. C. van Loosdrecht. 2010. "Upgrading of sewage treatment plant by sustainable and cost-effective separate treatment of industrial wastewater." Water Sci Technol 61 (7):1715-22. doi: 10.2166/wst.2010.977. Al-Tebrineh, Jamal, Leanne A. Pearson, Serhat A. Yasar, and Brett A. Neilan. 2012. "A multiplex qPCR targeting hepato- and neurotoxigenic cyanobacteria of global significance." Harmful Algae 15:19-25. doi: https://doi.org/10.1016/j.hal.2011.11.001. AP News. 2019. "Water officials halt $730,000 lake-wide treatment." AP News. https://apnews.com/a3889136a2ec4e558f6eb0378a9a8adc. AP News. 2020. "Cleanup costs of algae from Michigan lake worry homeowners." AP News. https://apnews.com/f5116f36c9a0f861e80556d268086ca2.

121 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Arif, M., J. Fletcher, S. M. Marek, U. Melcher, and F. M. Ochoa-Corona. 2013. "Development of a rapid, sensitive, and field-deployable razor ex BioDetection system and quantitative PCR assay for detection of Phymatotrichopsis omnivora using multiple gene targets." Appl Environ Microbiol 79 (7):2312-20. doi: 10.1128/AEM.03239-12. AWWA/WRF. 2015. "A Water Utility Manager’s Guide to Cyanotoxins ". American Water Works Association/Water Research Foundation. https://www.awwa.org/Portals/0/AWWA/Government/WaterUtilityManagersGuideToCy anotoxins.pdf?ver=2018-12-13-101839-130. Ayres, J. R., J. Awad, H. Burger, J. Marzouk, and J. van Leeuwen. 2019. "Investigation of the potential of buffalo and couch grasses to grow on AFIs and for removal of nutrients from paper mill wastewater." Water Science and Technology 79 (4):779-788. doi: 10.2166/wst.2019.098. Azevedo, S. M., W. W. Carmichael, E. M. Jochimsen, K. L. Rinehart, S. Lau, G. R. Shaw, and G. K. Eaglesham. 2002. "Human intoxication by microcystins during renal dialysis treatment in Caruaru-Brazil." Toxicology 181-182:441-6. doi: 10.1016/s0300- 483x(02)00491-2. Backer, L. C., J. H. Landsberg, M. Miller, K. Keel, and T. K. Taylor. 2013. "Canine cyanotoxin poisonings in the United States (1920s-2012): review of suspected and confirmed cases from three data sources." Toxins (Basel) 5 (9):1597-628. doi: 10.3390/toxins5091597. Backer, L. C., D. Manassaram-Baptiste, R. LePrell, and B. Bolton. 2015. "Cyanobacteria and algae blooms: Review of health and environmental data from the Harmful Algal Bloom- Related Illness Surveillance System (HABISS) 2007-2011." Toxins (Basel) 7 (4):1048- 64. doi: 10.3390/toxins7041048. Backer, L. C., and M. Miller. 2016. "Sentinel Animals in a One Health Approach to Harmful Cyanobacterial and Algal Blooms." Vet Sci 3 (2):8. doi: 10.3390/vetsci3020008. Baker, Louise, Barbara C. Sendall, Robin B. Gasser, Toni Menjivar, Brett A. Neilan, and Aaron R. Jex. 2013. "Rapid, multiplex-tandem PCR assay for automated detection and differentiation of toxigenic cyanobacterial blooms." Molecular and Cellular Probes 27 (5):208-214. doi: https://doi.org/10.1016/j.mcp.2013.07.001. Bates, Stephen S., David L. Garrison, and Rita A. Horner. 1998. "Bloom Dynamics and Physiology of Domoic-Acid Producing Pseudo-nitzschia Species " In Physiological ecology of harmful algal blooms, edited by D.M. Anderson, A. D. Cembella and G. M. Hallegraeff, 267-292. Heidleberg: Springer-Verlag. Beaulieu, Marieke, Frances Pick, and Irene Gregory-Eaves. 2013. "Nutrients and water temperature are significant predictors of cyanobacterial biomass in a 1147 lakes data set." Limnology and Oceanography 58 (5):1736-1746. doi: 10.4319/lo.2013.58.5.1736. Benayache, Naila-Yasmine, Tri Nguyen-Quang, Kateryna Hushchyna, Kayla McLellan, Fatima- Zohra Afri-Mehennaoui, and Noureddine Bouaïcha. 2019. "An Overview of Cyanobacteria Harmful Algal Bloom (CyanoHAB) Issues in Freshwater Ecosystems." In Limnology-Some New Aspects of Inland Water Ecology. IntechOpen. Beversdorf, L. J., K. Rude, C. A. Weirich, S. L. Bartlett, M. Seaman, C. Kozik, P. Biese, T. Gosz, M. Suha, C. Stempa, C. Shaw, C. Hedman, J. J. Piatt, and T. R. Miller. 2018. "Analysis of cyanobacterial metabolites in surface and raw drinking waters reveals more than microcystin." Water Res 140:280-290. doi: 10.1016/j.watres.2018.04.032. Bienfang, P. K., S. V. DeFelice, E. A. Laws, L. E. Brand, R. R. Bidigare, S. Christensen, H. Trapido-Rosenthal, T. K. Hemscheidt, D. J. McGillicuddy, D. M. Anderson, H. M. Solo-

122 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Gabriele, A. B. Boehm, and L. C. Backer. 2011. "Prominent Human Health Impacts from Several Marine Microbes: History, Ecology, and Public Health Implications." International Journal of Microbiology 2011:152815. doi: 10.1155/2011/152815. Biggs, B. J., Cathy Kilroy, Zealand New, and Environment Ministry for the. 2000. Stream periphyton monitoring manual. Christchurch, N.Z.: NIWA. Bingham, M, S.K. Sinha, and F Lupi. 2015. Economic Benefits of Reducing Harmful Algal Blooms in Lake Erie. Environemntal Consulting & Technology, Inc. Bouma-Gregson, Keith, Raphael M. Kudela, and Mary E. Power. 2018. "Widespread anatoxin-a detection in benthic cyanobacterial mats throughout a river network." PLOS ONE 13 (5):e0197669. doi: 10.1371/journal.pone.0197669. Brand, Larry E., Lisa Campbell, and Eileen Bresnan. 2012. "Karenia: The biology and ecology of a toxic genus." Harmful Algae 14:156-178. doi: https://doi.org/10.1016/j.hal.2011.10.020. Brandenburg, Karen, Laura Siebers, Joost Keuskamp, Thomas Jephcott, and Dedmer Van de Waal. 2020. "Effects of Nutrient Limitation on the Synthesis of N-Rich Phytoplankton Toxins: A Meta-Analysis." Toxins 12:221. doi: 10.3390/toxins12040221. Briand, J. F., S. Jacquet, C. Bernard, and J. F. Humbert. 2003. "Health hazards for terrestrial vertebrates from toxic cyanobacteria in surface water ecosystems." Vet Res 34 (4):361- 77. doi: 10.1051/vetres:2003019. Bullerjahn, George S, Robert M McKay, Timothy W Davis, David B Baker, Gregory L Boyer, Lesley V D’Anglada, Gregory J Doucette, Jeff C Ho, Elena G Irwin, and Catherine L Kling. 2016. "Global solutions to regional problems: Collecting global expertise to address the problem of harmful cyanobacterial blooms. A Lake Erie case study." Harmful Algae 54:223-238. Cai, Ting, Stephen Y. Park, and Yebo Li. 2013. "Nutrient recovery from wastewater streams by microalgae: Status and prospects." Renewable and Sustainable Energy Reviews 19:360- 369. doi: https://doi.org/10.1016/j.rser.2012.11.030. Calderón-Arrieta, Diego, Steven B. Caudill, and Franklin G. Mixon. 2019. "Valuing recreational water clarity and quality: evidence from hedonic pricing models of lakeshore properties." Applied Economics Letters 26 (3):237-244. doi: 10.1080/13504851.2018.1458187. Carey, C. C., B. W. Ibelings, E. P. Hoffmann, D. P. Hamilton, and J. D. Brookes. 2012. "Eco- physiological adaptations that favour freshwater cyanobacteria in a changing climate." Water Res 46 (5):1394-407. doi: 10.1016/j.watres.2011.12.016. Carmichael, W. W., S. M. Azevedo, J. S. An, R. J. Molica, E. M. Jochimsen, S. Lau, K. L. Rinehart, G. R. Shaw, and G. K. Eaglesham. 2001. "Human fatalities from cyanobacteria: chemical and biological evidence for cyanotoxins." Environ Health Perspect 109 (7):663-8. doi: 10.1289/ehp.01109663. Carmichael, Wayne W. 2001. "Health Effects of Toxin-Producing Cyanobacteria: “The CyanoHABs”." Human and Ecological Risk Assessment: An International Journal 7 (5):1393-1407. doi: 10.1080/20018091095087. Cavanagh, N., R. N. Nordin, L. G. Swain, and L. W. Pommen. Undated. "Lake and Stream Bottom Sediment Sampling Manua." BC Ministry of Environment, Lands and Parks. Water Quality Branch. https://www2.gov.bc.ca/assets/gov/environment/natural-resource- stewardship/nr-laws- policy/risc/lake_and_stream_bottom_sediment_sampling_manual.pdf.

123 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Cha, Y., K. H. Cho, H. Lee, T. Kang, and J. H. Kim. 2017. "The relative importance of water temperature and residence time in predicting cyanobacteria abundance in regulated rivers." Water Res 124:11-19. doi: 10.1016/j.watres.2017.07.040. Chia, Mathias A., Jennifer G. Jankowiak, Benjamin J. Kramer, Jennifer A. Goleski, I. Shuo Huang, Paul V. Zimba, Maria do Carmo Bittencourt-Oliveira, and Christopher J. Gobler. 2018. "Succession and toxicity of Microcystis and Anabaena (Dolichospermum) blooms are controlled by nutrient-dependent allelopathic interactions." Harmful Algae 74:67-77. doi: https://doi.org/10.1016/j.hal.2018.03.002. Chiu, Yi-Ting, Yi-Hsuan Chen, Ting-Shaun Wang, Hung-Kai Yen, and Tsair-Fuh Lin. 2017. "A qPCR-Based Tool to Diagnose the Presence of Harmful Cyanobacteria and Cyanotoxins in Drinking Water Sources." International journal of environmental research and public health 14 (5):547. doi: 10.3390/ijerph14050547. Chorus, Ingrid, and Jamie Bartram. 1999. Toxic cyanobacteria in water : a guide to their public health consequences, monitoring and management / edited by Ingrid Chorus and Jamie Bertram. Geneva: World Health Organization. Cirés, Samuel, Lars Wörmer, Ramsy Agha, and Antonio Quesada. 2013. "Overwintering populations of Anabaena, Aphanizomenon and Microcystis as potential inocula for summer blooms." Journal of Plankton Research 35 (6):1254-1266. doi: 10.1093/plankt/fbt081. Clark, John M., Blake A. Schaeffer, John A. Darling, Erin A. Urquhart, John M. Johnston, Amber Ignatius, Mark H. Myer, Keith A. Loftin, P. Jeremy Werdell, and Richard P. Stumpf. 2017. "Satellite monitoring of cyanobacterial harmful algal bloom frequency in recreational waters and drinking source waters." Ecological indicators 80:84-95. doi: 10.1016/j.ecolind.2017.04.046. Coffer, Megan M., Blake A. Schaeffer, John A. Darling, Erin A. Urquhart, and Wilson B. Salls. 2020. "Quantifying national and regional cyanobacterial occurrence in US lakes using satellite remote sensing." Ecological Indicators 111:105976. doi: https://doi.org/10.1016/j.ecolind.2019.105976. Comín, Francisco, José Romero, Oliver Hernández, and Margarita Menendez. 2001. "Restoration of Wetlands from Abandoned Rice Fields for Nutrient Removal, and Biological Community and Landscape Diversity." Restoration Ecology 9:201-208. doi: 10.1046/j.1526-100x.2001.009002201.x. Cornwell, J. C., H. Perez, K. G. Owens, K. G. Sellner, and D. Ferrier. 2016. Lake Linganore biogeochemial measurements - Sediment-water exchange rates of oxygen and nutrients from September 2016. In CCWS Contribution. Cambridge, MD: UMCES-HPL. Coyne, Kathryn J., Sara M. Handy, Elif Demir, Edward B. Whereat, David A. Hutchins, Kevin J. Portune, Martina A. Doblin, and S. Craig Cary. 2005. "Improved quantitative real-time PCR assays for enumeration of harmful algal species in field samples using an exogenous DNA reference standard." Limnology and Oceanography: Methods 3 (9):381-391. doi: 10.4319/lom.2005.3.381. Davis, Timothy, Matthew Harke, Maria Marcoval, Jennifer Goleski, Celia Orano-Dawson, Dianna Berry, and Christopher Gobler. 2010. "Effects of nitrogenous compounds and phosphorus on the growth of toxic and non-toxic strains of Microcystis during cyanobacterial blooms." Aquatic Microbial Ecology 61. doi: 10.3354/ame01445.

124 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

De, Mriganka, and Gurpal Toor. 2017. "Nitrogen transformations in the mounded drainfields of drip dispersal and gravel trench septic systems." Ecological Engineering 102:352-360. doi: 10.1016/j.ecoleng.2017.02.039. Deglint, Jason L., Chao Jin, Angela Chao, and Alexander Wong. 2018. The feasibility of automated identification of six algae types using neural networks and fluorescence-based spectral-morphological features. arXiv e-prints: arXiv:1805.01093. Accessed May 01, 2018. Doll, Cameron, Christopher R. Main, Colleen Bianco, Kathryn J. Coyne, and Dianne I. Greenfield. 2014. "Comparison of sandwich hybridization assay and quantitative PCR for the quantification of live and preserved cultures of Heterosigma akashiwo (Raphidophyceae)." Limnology and Oceanography: Methods 12 (4):232-245. doi: 10.4319/lom.2014.12.232. Dreher, Theo W., Lindsay P. Collart, Ryan S. Mueller, Kimberly H. Halsey, Robert J. Bildfell, Peter Schreder, Arya Sobhakumari, and Rodney Ferry. 2019. "Anabaena/Dolichospermum as the source of lethal microcystin levels responsible for a large cattle toxicosis event." Toxicon: X 1:100003. doi: https://doi.org/10.1016/j.toxcx.2018.100003. Edmondson, W. T. 1970. "Phosphorus, nitrogen, and algae in Lake Washington after diversion of sewage." Science 169 (3946):690-1. doi: 10.1126/science.169.3946.690. FDA. 2020. "Seafood Hazards Guidance Appendix 5. FDA and EPA Safety Levles in regulations and Guidance." Food and Drun Administration. https://www.fda.gov/media/80400/download. Ferrão-Filho, Aloysio da S., and Betina Kozlowsky-Suzuki. 2011. "Cyanotoxins: bioaccumulation and effects on aquatic animals." Marine drugs 9 (12):2729-2772. doi: 10.3390/md9122729. Fialko, Katie. 2018. "Three stregnths and Weaknesses of Water Quality Trading Policies." UNC Environmental Finance Center. http://efc.web.unc.edu/2018/04/26/three-strengths-and- weaknesses-of-water-quality-trading-policies/. Figueredo, Cleber C., Alessandra Giani, and David F. Bird. 2007. "Does Allelopathy Contribute to Cylindrospermopsis raciborskii (Cyanobaccteria) Bloom Occurrence and Geographic Expansion?1." Journal of Phycology 43 (2):256-265. doi: 10.1111/j.1529- 8817.2007.00333.x. Fiore, M. F., S. T. de Lima, W. W. Carmichael, S. M. K. McKinnie, J. R. Chekan, and B. S. Moore. 2020. "Guanitoxin, re-naming a cyanobacterial organophosphate toxin." Harmful Algae 92:101737. doi: 10.1016/j.hal.2019.101737. Foss, Amanda J., Christopher O. Miles, Ingunn A. Samdal, Kjersti E. Løvberg, Alistair L. Wilkins, Frode Rise, J. Atle H. Jaabæk, Peter C. McGowan, and Mark T. Aubel. 2018. "Analysis of free and metabolized microcystins in samples following a bird mortality event." Harmful Algae 80:117-129. doi: https://doi.org/10.1016/j.hal.2018.10.006. Gaget, V., P. Hobson, A. Keulen, K. Newton, P. Monis, A. R. Humpage, L. S. Weyrich, and J. D. Brookes. 2020. "Toolbox for the sampling and monitoring of benthic cyanobacteria." Water Res 169:115222. doi: 10.1016/j.watres.2019.115222. Gao, Y., J. C. Cornwell, D. K. Stoecker, and M. S. Owens. 2012. "Effects of cyanobacterial- driven pH increases on sediment nutrient fluxes and coupled nitrification-denitrification in a shallow fresh water estuary." Biogeosciences 9 (7):2697-2710. doi: 10.5194/bg-9- 2697-2012.

125 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Genkel, Charles, Jared Ervin, and Brandon Steets. 2019. "Nutrient Source Tracking to Support Modification of an Algae TMDL in the LA Region." California Stormwater Quality Association. Geosyntec Consultants. 2019. Final Report for the Septic System Impact to Surface Water Quality Study in Metropolitan Atlanta. Ger, Kemal, Elisabeth Faassen, Maria Pennino, and Miquel Lurling. 2016. "Effect of the toxin (microcystin) content of Microcystis on copepod grazing." Harmful Algae 52:34-45. doi: 10.1016/j.hal.2015.12.008. Gibble, Corinne, Kendra Negrey, and Raphael Kudela. 2017. "The use of blood collection cards for assessing presence of microcystin in marine and estuarine birds." Journal of Wildlife Rehabilitation 37:7-12. Gill, Laurence, Colin Doran, David Misstear, and Brendan Sheahan. 2009. "The use of recycled glass as a filter media for on-site wastewater treatment." Desalination and Water Treatment 4 (1-3):198-205. doi: 10.5004/dwt.2009.376. Glibert, PM, and JM Burkholder. 2006. "The complex relationships between increases in fertilization of the earth, coastal eutrophication and proliferation of harmful algal blooms." In Ecology of harmful algae, 341-354. Springer. Gobler, C. J., J. M. Burkholder, T. W. Davis, M. J. Harke, T. Johengen, C. A. Stow, and D. B. Van de Waal. 2016. "The dual role of nitrogen supply in controlling the growth and toxicity of cyanobacterial blooms." Harmful Algae 54:87-97. doi: 10.1016/j.hal.2016.01.010. Gobler, C.J. and Sunda, W.G. 2006. "Brown Tides." In Ecology of Harmful Algae. Ecological Studies (Analysis and Synthesis), edited by E. and Turner J.T Graneli. Springer, Berlin, Heidelberg Godhe, Anna, Donald Anderson, and Ann-Sofi Rehnstam-Holm. 2002. "PCR amplification of microalgal DNA for sequencing and species identification: Studies on fixatives and algal growth stages." Harmful Algae 1:375-382. doi: 10.1016/S1568-9883(02)00049-5. Graham, Jennifer L., Keith A. Loftin, Andrew C. Ziegler, and Michael T. Meyer. 2008. Guidelines for design and sampling for cyanobacterial toxin and taste-and-odor studies in lakes and reservoirs. In Scientific Investigations Report. Reston, VA. Griffith, Andrew W., and Christopher J. Gobler. 2020. "Harmful algal blooms: A climate change co-stressor in marine and freshwater ecosystems." Harmful Algae 91:101590. doi: https://doi.org/10.1016/j.hal.2019.03.008. Guiry, Michael. 2019. "Algae." accessed 7/12/2019. https://eol.org/docs/discover/algae. Guo, Tian, Erik C Nisbet, and Jay F Martin. 2019. "Identifying mechanisms of environmental decision-making: How ideology and geographic proximity influence public support for managing agricultural runoff to curb harmful algal blooms." Journal of environmental management 241:264-272. Hamilton, T. , Bryant, D. , & Macalady, J. 2015. "The role of biology in planetary evolution: cyanobacterial primary production in low-oxygen Proterozoic oceans." Environ Microbiol 18 (2). doi: 10.1111/1462-2920.13118. Harke, Matthew J., Timothy W. Davis, Susan B. Watson, and Christopher J. Gobler. 2016. "Nutrient-Controlled Niche Differentiation of Western Lake Erie Cyanobacterial Populations Revealed via Metatranscriptomic Surveys." Environmental Science & Technology 50 (2):604-615. doi: 10.1021/acs.est.5b03931.

126 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Harke, Matthew J., and Christopher J. Gobler. 2013. "Global Transcriptional Responses of the Toxic Cyanobacterium, Microcystis aeruginosa, to Nitrogen Stress, Phosphorus Stress, and Growth on Organic Matter." PLOS ONE 8 (7):e69834. doi: 10.1371/journal.pone.0069834. Hauxwell, Jennifer, Susan Knight, Kelly Wagner, Alison Mikulyuk, Michelle Nault, Meghan Porzky, and Shaunna Chase. 2010. "Recommended baseline monitoring of aquatic plants in Wisconsin: sampling design, field and laboratory procedures, data entry and analysis, and applications PUB-SS-1068 2010." Madison, WI: Wisconsin Department of Natural Resources Bureau of Science Services, . Heisler, John, Patricia M Glibert, JoAnn M Burkholder, Donald M Anderson, William Cochlan, William C Dennison, Quay Dortch, Christopher J Gobler, Cynthia A Heil, and Edythe Humphries. 2008. "Eutrophication and harmful algal blooms: a scientific consensus." Harmful algae 8 (1):3-13. Hendriks, Alexander TWM, and Jeroen G Langeveld. 2017. Rethinking wastewater treatment plant effluent standards: nutrient reduction or nutrient control? : ACS Publications. Henesey, J. , J. Wolny, and K. G Sellner. In preparation. Hilborn, E. D., V. A. Roberts, L. Backer, E. Deconno, J. S. Egan, J. B. Hyde, D. C. Nicholas, E. J. Wiegert, L. M. Billing, M. Diorio, M. C. Mohr, J. F. Hardy, T. J. Wade, J. S. Yoder, M. C. Hlavsa, Control Centers for Disease, and Prevention. 2014. "Algal bloom- associated disease outbreaks among users of freshwater lakes--United States, 2009- 2010." MMWR Morb Mortal Wkly Rep 63 (1):11-5. Holland, Aleicia, and Susan Kinnear. 2013. "Interpreting the Possible Ecological Role(s) of Cyanotoxins: Compounds for Competitive Advantage and/or Physiological Aide?" Marine drugs 11:2239-2258. doi: 10.3390/md11072239. Howard, Meredith D. A., Carey Nagoda, Raphael M. Kudela, Kendra Hayashi, Avery Tatters, David A. Caron, Lilian Busse, Jeff Brown, Martha Sutula, and Eric D. Stein. 2017. "Microcystin Prevalence throughout Lentic Waterbodies in Coastal Southern California." Toxins 9 (7):231. doi: 10.3390/toxins9070231. Hrycik, Allison R, Angela Shambaugh, and Jason D Stockwell. 2019. "Comparison of FlowCAM and microscope biovolume measurements for a diverse freshwater phytoplankton community." Journal of Plankton Research 41 (6):849-864. doi: 10.1093/plankt/fbz056. IOCCG. 2018. "IOCCG Report 17. Earth Observations in Support of Global Water Quality Monitoring." International Ocean Colour Coordinating Group. https://ioccg.org/wp- content/uploads/2018/09/ioccg_report_17-wq-rr.pdf. ITIS. 2020. "Integrated Taxonomic Information System." accessed 4/1/2020. https://www.itis.gov/. Janke, B. D., J. C. Finlay, and S. E. Hobbie. 2017. "Trees and Streets as Drivers of Urban Stormwater Nutrient Pollution." Environ Sci Technol 51 (17):9569-9579. doi: 10.1021/acs.est.7b02225. Janssen, E. M. 2019. "Cyanobacterial peptides beyond microcystins - A review on co- occurrence, toxicity, and challenges for risk assessment." Water Res 151:488-499. doi: 10.1016/j.watres.2018.12.048. Jin, C., M. M. F. Mesquita, J. L. Deglint, M. B. Emelko, and A. Wong. 2018. "Quantification of cyanobacterial cells via a novel imaging-driven technique with an integrated fluorescence signature." Sci Rep 8 (1):9055. doi: 10.1038/s41598-018-27406-0.

127 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Jochimsen, E. M., W. W. Carmichael, J. S. An, D. M. Cardo, S. T. Cookson, C. E. Holmes, M. B. Antunes, D. A. de Melo Filho, T. M. Lyra, V. S. Barreto, S. M. Azevedo, and W. R. Jarvis. 1998. "Liver failure and death after exposure to microcystins at a hemodialysis center in Brazil." N Engl J Med 338 (13):873-8. doi: 10.1056/nejm199803263381304. Jordan, T. E., D. F. Whigham, K. H. Hofmockel, and M. A. Pittek. 2003. "Nutrient and sediment removal by a restored wetland receiving agricultural runoff." J Environ Qual 32 (4):1534-47. doi: 10.2134/jeq2003.1534. Kashian, R, and J Kasper. 2010. "Tainter Lake and Lake Menomin - The Impact fo Diminishing Water Quality on Value." Department of Economics, University of Wisconsin. KDHE. 2011. "Cheney Lake Watershed Restoration and Protection Plan." Kansas Department of Health and the Environment. https://www.kdheks.gov/nps/wraps/CheneyLake_Plan&Summary.pdf. Kemp, Thomas, Irene Ng, and Haikal Mohammad. 2017. "The Impact of Water Clarity on Home Value in Northern Wisconsin." The Appraisal Journal 85 (4). Kislik, Emily Chippie, Iryna Dronova, and Maggi Kelly. 2018. "UAVs in Support of Algal Bloom Research: A Review of Current Applications and Future Opportunities." Drones 2. doi: 10.3390/drones2040035. Knud-Hansen, C. 1994. " Historical perspective of the phosphate detergent conflict." Natural Resources and Environmental Policy Seminar, University of Colorado, Boulder, CO. Kosten, Sarian, Vera L. M. Huszar, Eloy Bécares, Luciana S. Costa, Ellen van Donk, Lars- Anders Hansson, Erik Jeppesen, Carla Kruk, Gissell Lacerot, Néstor Mazzeo, Luc De Meester, Brian Moss, Miquel Lürling, Tiina Nõges, Susana Romo, and Marten Scheffer. 2012. "Warmer climates boost cyanobacterial dominance in shallow lakes." Global Change Biology 18 (1):118-126. doi: 10.1111/j.1365-2486.2011.02488.x. Kromkamp, Jacco. 1987. "Formation and functional significance of storage products in cyanobacteria." New Zealand Journal of Marine and Freshwater Research 21 (3):457- 465. doi: 10.1080/00288330.1987.9516241. Kumar, Krithika, Rodrigo A Mella-Herrera, and James W Golden. 2010. "Cyanobacterial heterocysts." Cold Spring Harbor perspectives in biology 2 (4):a000315. doi: 10.1101/cshperspect.a000315. Kuniyoshi, T. M., E. Sevilla, M. T. Bes, M. F. Fillat, and M. L. Peleato. 2013. "Phosphate deficiency (N/P 40:1) induces mcyD transcription and microcystin synthesis in Microcystis aeruginosa PCC7806." Plant Physiol Biochem 65:120-4. doi: 10.1016/j.plaphy.2013.01.011. Leão, Pedro N., Alban R. Pereira, Wei-Ting Liu, Julio Ng, Pavel A. Pevzner, Pieter C. Dorrestein, Gabriele M. König, Vitor M. Vasconcelos, and William H. Gerwick. 2010. "Synergistic allelochemicals from a freshwater cyanobacterium." Proceedings of the National Academy of Sciences 107 (25):11183-11188. doi: 10.1073/pnas.0914343107. Lee, S., X. Jiang, M. Manubolu, K. Riedl, S. A. Ludsin, J. F. Martin, and J. Lee. 2017. "Fresh produce and their soils accumulate cyanotoxins from irrigation water: Implications for public health and food security." Food Res Int 102:234-245. doi: 10.1016/j.foodres.2017.09.079. Lehman, John T, Douglas W Bell, and Kahli E McDonald. 2009. "Reduced river phosphorus following implementation of a lawn fertilizer ordinance." Lake and Reservoir Management 25 (3):307-312.

128 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Levesque, B., M. C. Gervais, P. Chevalier, D. Gauvin, E. Anassour-Laouan-Sidi, S. Gingras, N. Fortin, G. Brisson, C. Greer, and D. Bird. 2014. "Prospective study of acute health effects in relation to exposure to cyanobacteria." Sci Total Environ 466-467:397-403. doi: 10.1016/j.scitotenv.2013.07.045. Lopez-Rodas, V., E. Maneiro, M. P. Lanzarot, N. Perdigones, and E. Costas. 2008. "Mass wildlife mortality due to cyanobacteria in the Donana National Park, Spain." Vet Rec 162 (10):317-8. doi: 10.1136/vr.162.10.317. Lyon, Thomas P, and John W Maxwell. 1999. "'Voluntary'Approaches to Environmental Regulation: A Survey." Available at SSRN 147888. Malanga, G., L. Giannuzzi, and M. Hernando. 2019. "The possible role of microcystin (D-Leu(1) MC-LR) as an antioxidant on Microcystis aeruginosa (Cyanophyceae). In vitro and in vivo evidence." Comp Biochem Physiol C Toxicol Pharmacol 225:108575. doi: 10.1016/j.cbpc.2019.108575. Manning, S.W. , and J. W. II LaClaire. 2010. "Prymnesins: Toxic Metabolites of the Golden Alga, Prymnesium parvum Carter (Haptophyta)." Marine Drugs 8 (3):678-704. doi: https://doi.org/10.3390/md8030678. Masoner, Jason R, Dana W Kolpin, Isabelle M Cozzarelli, Larry B Barber, David S Burden, William T Foreman, Kenneth J Forshay, Edward T Furlong, Justin F Groves, and Michelle L Hladik. 2019. "Urban stormwater: An overlooked pathway of extensive mixed contaminants to surface and groundwaters in the United States." Environmental science & technology 53 (17):10070-10081. Mattheiss, J, K. G. Sellner, and D. Ferrier. 2017. Lake Linganore Water Quality Monitoring: May 2016 – March 2017 In CCWS Contribution #17-03. Frederick, MD: Center for Coastal and Watershed Studies, Hood College. Mayer, P. M., S. K. Reynolds, Jr., M. D. McCutchen, and T. J. Canfield. 2007. "Meta-analysis of nitrogen removal in riparian buffers." J Environ Qual 36 (4):1172-80. doi: 10.2134/jeq2006.0462. McInnes, Allison, and Antonietta Quigg. 2010. "Near-Annual Fish Kills in Small Embayments: Casual vs. Causal Factors." Journal of Coastal Research:957-966. doi: 10.2112/JCOASTRES-D-10-00006.1. MDEQ. 2015. "USER GUIDE – Optimization Methods and Best Management Practices for Facultative Lagoons." Montana DEQ, Water Quality Planning Bureau https://deq.mt.gov/Portals/112/Water/TFAB/WPCSRF/pdf/FacultativeLagoonUserGuide FINAL5292015.pdf. Medlin, L. K., and J. Orozco. 2017. "Molecular Techniques for the Detection of Organisms in Aquatic Environments, with Emphasis on Harmful Algal Bloom Species." Sensors (Basel) 17 (5). doi: 10.3390/s17051184. Mez, Konstanze, Kenneth Beattie, Geoffrey Codd, Kurt Hanselmann, Beat Hauser, Hanspeter Naegeli, and Hans Preisig. 1997. "Identification of a microcystin in benthic cyanobacteria linked to cattle deaths on alpine pastures in Switzerland." European Journal of Phycology 32 (2):111-117. doi: 10.1080/09670269710001737029. Miller, Melissa A., Raphael M. Kudela, Abdu Mekebri, Dave Crane, Stori C. Oates, M. Timothy Tinker, Michelle Staedler, Woutrina A. Miller, Sharon Toy-Choutka, Clare Dominik, Dane Hardin, Gregg Langlois, Michael Murray, Kim Ward, and David A. Jessup. 2010. "Evidence for a Novel Marine Harmful Algal Bloom: Cyanotoxin (Microcystin) Transfer from Land to Sea Otters." PLOS ONE 5 (9):e12576. doi: 10.1371/journal.pone.0012576.

129 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Mishra, Sachidananda, Richard P. Stumpf, Blake A. Schaeffer, P. Jeremy Werdell, Keith A. Loftin, and Andrew Meredith. 2019. "Measurement of Cyanobacterial Bloom Magnitude using Satellite Remote Sensing." Scientific Reports 9 (1):18310. doi: 10.1038/s41598- 019-54453-y. Monchamp, Marie-Eve, Frances R. Pick, Beatrix E. Beisner, and Roxane Maranger. 2014. "Nitrogen Forms Influence Microcystin Concentration and Composition via Changes in Cyanobacterial Community Structure." PLOS ONE 9 (1):e85573. doi: 10.1371/journal.pone.0085573. Morales-Williams, Ana M., Alan D. Wanamaker, and John A. Downing. 2017. "Cyanobacterial carbon concentrating mechanisms facilitate sustained CO2 depletion in eutrophic lakes." Biogeosciences 14:2865-2875. doi: 10.5194/bg-14-2865-2017. Moss, Brian, Sarian Kosten, Mariana Meerhoff, Richard W. Battarbee, Erik Jeppesen, Néstor Mazzeo, Karl Havens, Gissell Lacerot, Zhengwen Liu, Luc De Meester, Hans Paerl, and Marten Scheffer. 2011. "Allied attack: climate change and eutrophication." Inland Waters 1 (2):101-105. doi: 10.5268/IW-1.2.359. Moy, N. J., J. Dodson, S. J. Tassone, P. A. Bukaveckas, and L. P. Bulluck. 2016. "Biotransport of Algal Toxins to Riparian Food Webs." Environ Sci Technol 50 (18):10007-14. doi: 10.1021/acs.est.6b02760. MPCA. 2015a. "Industrial Stormwater: Best Management Practices Guidebook." Minneosta Pollution Control Agency. https://www.pca.state.mn.us/sites/default/files/wq-strm3- 26.pdf. MPCA. 2015b. "Industrial Stormwater: Best Management Practices Guidebook. Version 1.1. ." Minnesota Pollution Control Agency. https://www.pca.state.mn.us/sites/default/files/wq- strm3-26.pdf MPCA. 2019. "Water Quality Trading." National Small Flows Clearinghouse. 1999. "Mounds: A Septic System Alternative." Pipeline 10 (3). Newcombe, Gayle, Jenny House, Lionel Ho, Peter Baker, and Michael Burch. 2010. "Management Strategies for Cyanobacteria (Blue-Green Algae): A Guide for Water Utilities, Research Report 74." Adelaide, SA: Water Quality Research Australia https://www.epa.state.oh.us/Portals/28/documents/habs/ManagementStrategies_BGA.pdf. Ngwa, Felexce F., Chandra A. Madramootoo, and Suha Jabaji. 2014. "Development and application of a multiplex qPCR technique to detect multiple microcystin-producing cyanobacterial genera in a Canadian freshwater lake." Journal of Applied Phycology 26 (4):1675-1687. doi: 10.1007/s10811-013-0199-9. NVPDC. 1996. "Nonstructural Urban BMP Handbook – A Guide to Nonpoint Source Pollution Prevention and Control through Nonstructural Measures." Annandale, VA: Northern Virginia Planning District Commission for the Virginia Department of Conservation and Recreation, Division of Soil and Water Conservation https://www.novaregion.org/DocumentCenter/View/1676/NSBMP1?bidId=. NYDEC. 2019. "Harmful Algal Blooms (HABS) Program Guide, Version 3." New York Department of Environmental Conservation. http://www.dec.ny.gov/docs/water_pdf/habsprogramguide.pdf. O’Neil, J. M., T. W. Davis, M. A. Burford, and C. J. Gobler. 2012. "The rise of harmful cyanobacteria blooms: The potential roles of eutrophication and climate change." Harmful Algae 14:313-334. doi: https://doi.org/10.1016/j.hal.2011.10.027.

130 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

OCDWEP. 2009. "Onondaga Lake Ambient Monitoring Program: 2007 Annual Report.". Onondaga County Department of Water Environment Protection. OECD. 2003. Voluntary approaches for environmental policy: Effectiveness, efficiency and usage in policy mixes. OECD Paris. OEHHA. 2012. "Toxicological Summary and Suggested Action Levels to Reduce Potential Adverse Health Effects of Six Cyanotoxins ". Sacramento, CA: California Environmental Protection Agency, Office of Environmental Health Hazard Assessment https://www.waterboards.ca.gov/water_issues/programs/peer_review/docs/calif_cyanotox ins/cyanotoxins053112.pdf. Ohio EPA. 2020. "Public Water System Harmful Algal Bloom Response Strategy ". Ohio Environmental Protection Agency, Division of Drinking and Ground Waters. https://epa.ohio.gov/Portals/28/documents/habs/2020-PWS-HAB-Strategy.pdf. Oziol, L., and N. Bouaicha. 2010. "First evidence of estrogenic potential of the cyanobacterial heptotoxins the nodularin-R and the microcystin-LR in cultured mammalian cells." J Hazard Mater 174 (1-3):610-5. doi: 10.1016/j.jhazmat.2009.09.095. Paerl, H. W., R. S. Fulton, 3rd, P. H. Moisander, and J. Dyble. 2001. "Harmful freshwater algal blooms, with an emphasis on cyanobacteria." ScientificWorldJournal 1:76-113. doi: 10.1100/tsw.2001.16. Paerl, H. W., N. S. Hall, A. G. Hounshell, R. A. Luettich, Jr., K. L. Rossignol, C. L. Osburn, and J. Bales. 2019. "Recent increase in catastrophic tropical cyclone flooding in coastal North Carolina, USA: Long-term observations suggest a regime shift." Sci Rep 9 (1):10620. doi: 10.1038/s41598-019-46928-9. Paerl, H. W., and J. Huisman. 2009. "Climate change: a catalyst for global expansion of harmful cyanobacterial blooms." Environ Microbiol Rep 1 (1):27-37. doi: 10.1111/j.1758- 2229.2008.00004.x. Paerl, H. W., and T. G. Otten. 2013. "Harmful cyanobacterial blooms: causes, consequences, and controls." Microb Ecol 65 (4):995-1010. doi: 10.1007/s00248-012-0159-y. Paerl, H. W., and T. G. Otten. 2016. "Duelling 'CyanoHABs': unravelling the environmental drivers controlling dominance and succession among diazotrophic and non-N2 -fixing harmful cyanobacteria." Environ Microbiol 18 (2):316-24. doi: 10.1111/1462- 2920.13035. Paerl, H. W., and V. J. Paul. 2012. "Climate change: links to global expansion of harmful cyanobacteria." Water Res 46 (5):1349-63. doi: 10.1016/j.watres.2011.08.002. Paerl, Hans. 2018. "Mitigating toxic planktonic cyanobacterial blooms in aquatic ecosystems facing increasing anthropogenic and climatic pressures." Toxins 10 (2):76. doi: 10.3390/toxins10020076. Paerl, Hans W. 1985. "Microzone formation: Its role in the enhancement of aquatic N2 fixation1." Limnology and Oceanography 30 (6):1246-1252. doi: 10.4319/lo.1985.30.6.1246. Pearson, L. A., E. Dittmann, R. Mazmouz, S. E. Ongley, P. M. D'Agostino, and B. A. Neilan. 2016. "The genetics, biosynthesis and regulation of toxic specialized metabolites of cyanobacteria." Harmful Algae 54:98-111. doi: 10.1016/j.hal.2015.11.002. Pearson, L. A., and B. A. Neilan. 2008. "The molecular genetics of cyanobacterial toxicity as a basis for monitoring water quality and public health risk." Curr Opin Biotechnol 19 (3):281-8. doi: 10.1016/j.copbio.2008.03.002.

131 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Pecher, Wolf T, M Emad Al Madadha, Priya DasSarma, Folasade Ekulona, Eric J Schott, Kelli Crowe, Bojana Stojkovic Gut, and Shiladitya DasSarma. 2019. "Effects of road salt on microbial communities: Halophiles as biomarkers of road salt pollution." PloS one 14 (9). Pendall, Rolf, and Stephan Schmidt. 2011. "Who joins advocacy organizations? Water quality and participation in rural shoreline Great Lakes communities." Journal of Great Lakes Research 37 (2):245-255. Persaud, Ann, Kamal Alsharif, Paul Monaghan, Fenda Akiwumi, Maria C Morera, and Emily Ott. 2016. "Landscaping practices, community perceptions, and social indicators for stormwater nonpoint source pollution management." Sustainable cities and society 27:377-385. Pimentel, Juliana da Silva, and Alessandra Giani. 2013. "Estimating toxic cyanobacteria in a Brazilian reservoir by quantitative real-time PCR, based on the microcystin synthetase D gene." Journal of applied phycology 25:1545. doi: 10.1007/s10811-013-9996-4. Qu, Kaiyang, Fei Guo, Xiangrong Liu, Yuan Lin, and Quan Zou. 2019. "Application of Machine Learning in Microbiology." Frontiers in Microbiology 10 (827). doi: 10.3389/fmicb.2019.00827. Quiblier, Catherine, Susanna Wood, Isidora Echenique, Mark Heath, Villeneuve Aurelie, and Jean-François Humbert. 2013. "A review of current knowledge on toxic benthic freshwater cyanobacteria - Ecology, toxin production and risk management." Water research 47. doi: 10.1016/j.watres.2013.06.042. Reynolds, C. S. 2006. The Ecology of Phytoplankton, Ecology, Biodiversity and Conservation. Cambridge: Cambridge University Press. Richards, S., P. J. Withers, E. Paterson, C. W. McRoberts, and M. Stutter. 2016. "Temporal variability in domestic point source discharges and their associated impact on receiving waters." Sci Total Environ 571:1275-83. doi: 10.1016/j.scitotenv.2016.07.166. Rodríguez, E., G. D. Onstad, T. P. Kull, J. S. Metcalf, J. L. Acero, and U. von Gunten. 2007. "Oxidative elimination of cyanotoxins: comparison of ozone, chlorine, chlorine dioxide and permanganate." Water Res 41 (15):3381-93. doi: 10.1016/j.watres.2007.03.033. Rodusky, Andy, Bruce Sharfstein, Therese East, and Ryan Maki. 2005. "A Comparison of Three Methods to Collect Submerged Aquatic Vegetation in a Shallow Lake." Environmental monitoring and assessment 110:87-97. doi: 10.1007/s10661-005-6338-2. Romo, Susana, JUAN SORIA, FRANCISCA FERNÁNDEZ, YOUNESS OUAHID, and ÁNGEL BARÓN-SOLÁ. 2012. "Water residence time and the dynamics of toxic cyanobacteria." Freshwater Biology 58 (3):513-522. doi: 10.1111/j.1365- 2427.2012.02734.x. Rosen, Barry H., and Ann St. Amand. 2015. Field and laboratory guide to freshwater cyanobacteria harmful algal blooms for Native American and Alaska Native communities. In Open-File Report. Reston, VA. Roué, M., H. T. Darius, and M. Chinain. 2018. "Solid Phase Adsorption Toxin Tracking (SPATT) Technology for the Monitoring of Aquatic Toxins: A Review." Toxins (Basel) 10 (4). doi: 10.3390/toxins10040167. Sanan, T., Jim Lazorchak, D. Sundaravadivelu, J. Kickish, J. Jones, and R. Venkatapathy. 2019. "Development of methods for measuring total microcystins in Fish Tissue using the 2- methoxy-3-methyl-4-phenylbutyric acid (MMPB) procedure " SETAC North America 40th National Meeting, Toronto, CA.

132 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Sanseverino, Isabella, Diana Sofia CONDUTO ANTÓNIO, Luca POZZOLI, Srdan DOBRICIC, and Teresa LETTIERI. 2016. Algal bloom and its economic impact Sarnelle, Orlando. 2007. "Initial conditions mediate the interaction between Daphnia and bloom- forming cyanobacteria." Limnology and Oceanography 52 (5):2120-2127. doi: 10.4319/lo.2007.52.5.2120. SBA. 2020. SBA Offers Disaster Assistance to Small Businesses in Mississippi Affected by Blue-green Algae on the Gulf Coast of Mississippi. Washington, D. C.: Small Business Administration. https://www.sba.gov/about-sba/sba-newsroom/press-releases-media- advisories/sba-offers-disaster-assistance-small-businesses-mississippi-affected-blue- green-algae-gulf-coast. Schechinger, Anne. 2019. "The Huge Cost of Toxic Algae Contamination." AgMag. Scheffer, Marten. 1997. "Ecology of Shallow Lakes

" Population and Community Biology Series. Scholin, Christopher, Gregory Doucette, Scott Jensen, Brent Roman, Douglas Pargett, Roman Marin, Christina Preston, William Jones, Jason Feldman, Cheri Everlove, Adeline Harris, Nilo Alvarado, Eugene Massion, James Birch, Dianne Greenfield, Robert Vrijenhoek, Christina Mikulski, and Kelly Jones. 2009. "REMOTE DETECTION OF MARINE MICROBES, SMALL INVERTEBRATES, HARMFUL ALGAE, AND BIOTOXINS USING THE ENVIRONMENTAL SAMPLE PROCESSOR (ESP)." Oceanography 22 (2):158-167. Seitzinger, Sybil P. 1991. "The effect of pH on the release of phosphorus from Potomac estuary sediments: Implications for blue-green algal blooms." Estuarine, Coastal and Shelf Science 33 (4):409-418. doi: https://doi.org/10.1016/0272-7714(91)90065-J. Sellner, K. G., G. J. Doucette, and G. J. Kirkpatrick. 2003. "Harmful algal blooms: causes, impacts and detection." J Ind Microbiol Biotechnol 30 (7):383-406. doi: 10.1007/s10295-003-0074-9. Silverman, G. S. 2005. "The effectiveness of education as a tool to manage onsite septic systems." The Free Library. Smith, Douglas R., Kevin W. King, and Mark R. Williams. 2015. "What is causing the harmful algal blooms in Lake Erie?" Journal of Soil and Water Conservation 70 (2):27A-29A. doi: 10.2489/jswc.70.2.27A. Smith, R. B., B. Bass, D. Sawyer, D. Depew, and S. B. Watson. 2019. "Estimating the economic costs of algal blooms in the Canadian Lake Erie Basin." Harmful Algae 87:101624. doi: 10.1016/j.hal.2019.101624. Smith, Z. J., R. M. Martin, B. Wei, S. W. Wilhelm, and G. L. Boyer. 2019. "Spatial and Temporal Variation in Paralytic Shellfish Toxin Production by Benthic Microseira (Lyngbya) wollei in a Freshwater New York Lake." Toxins (Basel) 11 (1). doi: 10.3390/toxins11010044. Stanfield, Kevin. 2018. "DEVELOPING METHODS TO DIFFERENTIATE SPECIES AND ESTIMATE COVERAGE OF BENTHIC AUTOTROPHS IN THE POTOMAC USING DIGITAL IMAGING." M. S. Thesis, Environmental Biology, Hood College. Steffensen, D. A. 2008. "Economic cost of cyanobacterial blooms." In Cyanobacterial Harmful Algal Blooms: State of the Science and Research Needs. Advances in Experimental Medicine and Biology, edited by H. K. Hudnell. New York: Springer.

133 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Stewart, I., A. A. Seawright, and G. R. Shaw. 2008. "Cyanobacterial poisoning in livestock, wild mammals and birds--an overview." Adv Exp Med Biol 619:613-37. doi: 10.1007/978-0- 387-75865-7_28. Tan, K., Z. Huang, R. Ji, Y. Qiu, Z. Wang, and J. Liu. 2019. "A review of allelopathy on microalgae." Microbiology 165 (6):587-592. doi: 10.1099/mic.0.000776. Taylor, Thomas N., and Edith L. Taylor. 1993. Biology and Evolution of Fossil Plants. New Jersey: Prentiss Hall. Te, S. H., E. Y. Chen, and K. Y. Gin. 2015. "Comparison of Quantitative PCR and Droplet Digital PCR Multiplex Assays for Two Genera of Bloom-Forming Cyanobacteria, Cylindrospermopsis and Microcystis." Appl Environ Microbiol 81 (15):5203-11. doi: 10.1128/aem.00931-15. Tobiessen, Peter. 2012. The secret life of a lake : the ecology of northern lakes and their stewardship. Niskayuna, N.Y.: Graphite Press. Tonk, Linda, Kim Bosch, Petra Visser, and Jef Huisman. 2007. "Tonk L, Bosch K, Visser PM, Huisman J.. Salt tolerance of the harmful cyanobacterium Microcystis aeruginosa. Aquat Microb Ecol 46: 117-123." Aquatic Microbial Ecology 46. doi: 10.3354/ame046117. U. S. Congress. 2019. "SOUTH FLORIDA CLEAN COASTAL WATERS ACT OF 2019." Washington, D. C.: House of Representatives Report 116-202. UMRBA. 2020. "Upper Mississippi River Harmful Algal Bloom Response Resource Manual. UMR HAB Tools and Resources." Upper Mississippi River Basin Association http://www.umrba.org/wq/umr-hab-response-resource-manual.pdf. Urquhart, Erin A., Blake A. Schaeffer, Richard P. Stumpf, Keith A. Loftin, and P. Jeremy Werdell. 2017. "A method for examining temporal changes in cyanobacterial harmful algal bloom spatial extent using satellite remote sensing." Harmful Algae 67:144-152. doi: https://doi.org/10.1016/j.hal.2017.06.001. USEPA. 1998. "National Water Quality Inventory: 1996 Report to Congress. EPA 841-R-97- 008." Wahsington, D. C.: U. S. Environemtnal Protection Agency. USEPA. 1999. "Decentralized Systems Technology Fact Sheet Recirculating Sand Filters EPA 832-F-99-079 ". U. S. Environmental Protection Agency, Office of Water. https://www.epa.gov/sites/production/files/2015-06/documents/finalr_7e6.pdf. USEPA. 2005a. "Decentralized Wastewater Treatment Systems A Program Strategy EPA 832-R- 05-002." U. S. Environmental Protection Agency, Office of Water. https://www.epa.gov/sites/production/files/2015- 06/documents/septic_program_strategy.pdf. USEPA. 2005b. "Riparian Buffer Width, Vegetative Cover, and Nitrogen Removal Effectiveness: A Review of Current Science and Regulations EPA/600/R-05/118 ". Ada, OK: U. S. Environmental Protectino Agency, Office of Research and Development. https://www.epa.gov/sites/production/files/2019-02/documents/riparian-buffer-width- 2005.pdf. USEPA. 2007. "National Management Measures to Control Nonpoint Source Pollution from Hydromodification EPA 841-B-07-002." U. S. Environmental Protection Agency. https://www.epa.gov/sites/production/files/2015-09/documents/hydromod_all_web.pdf. USEPA. 2008. "Handbook for Developing Watershed Plans to Restore and Protect Our Waters EPA 841-B-08-002." Washington, D. C. : U. S. Environmental Protection Agency, Office of Water. https://www.epa.gov/sites/production/files/2015- 09/documents/2008_04_18_nps_watershed_handbook_handbook-2.pdf.

134 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

USEPA. 2009. "Nutrient Design Control Manual EPA/600/R‐09/012 ". United States Environmental Protection Agency, Offie of Research and Development. https://www.epa.gov/sites/production/files/2019-02/documents/nutrient-control-design- manual-state-tech.pdf. USEPA. 2011. "Principles of Design and Operations of Wastewater Treatment Pond Systems for Plant Operators, Engineers, and Managers EPA/600/R-11/088 ". United States Environmental Protection Agency, Office of Research and Development. https://www.epa.gov/sites/production/files/2014-09/documents/lagoon-pond-treatment- 2011.pdf. USEPA. 2013. "A Quick Guide to Developing Watershed Plans to Restore and Protect Our Waters EPA 841-R-13-003." Washington, D. C. : U. S. Environmental Protection Agency, Office of Wetlands, Oceans and Watersheds. https://www.epa.gov/sites/production/files/2015- 12/documents/watershed_mgmnt_quick_guide.pdf. USEPA. 2015a. "Case Studies on Implementing Low-Cost Modifications to Improve Nutrient Reduction at Wastewater Treatment Plants EPA-841-R-15-004 ". United States Environmental Protection Agency. https://www.epa.gov/sites/production/files/2015- 08/documents/case_studies_on_implementing_low- cost_modification_to_improve_potw_nutrient_reduction-combined_508_-_august.pdf. USEPA. 2015b. "A Compilation of Cost Data Associated with the Impaccts and Control of Nutrient Pollution EPA 820-F-15-096." Washington D. C. : U. S. Environmental Protection Agency. https://www.epa.gov/sites/production/files/2015- 04/documents/nutrient-economics-report-2015.pdf. USEPA. 2015c. " Drinking Water Health Advisory for the Cyanobacterial Toxin Cylindrospermopsin EPA-820R15101." Washington, D. C.: U. S. Environmental Protection Agency, Office of Water. https://www.epa.gov/sites/production/files/2017- 06/documents/cylindrospermopsin-report-2015.pdf. USEPA. 2015d. "Drinking Water Health Advisory for the Cyanobacterial Microcystin Toxins EPA 820R15100 ". Washington, D, C,: U. S. Environmental Protection Agency, Office of Water. https://www.epa.gov/sites/production/files/2017-06/documents/microcystins- report-2015.pdf. USEPA. 2015e. "Health Effects Support Document for the Cyanobacterial Toxin Anatoxin-A EPA-820R15104 ". Washington, D. C. : U. S. Environmental Protection Agency, Office of Water. https://www.epa.gov/sites/production/files/2017-06/documents/anatoxin-a- report-2015.pdf. USEPA. 2015f. "Health Effects Support Document for the Cyanobacterial Toxin Cylindrospermopsin EPA-820R15103 ". Washington, D. C. : U. S. Environmental Protection Agency, Office of Water. https://www.epa.gov/sites/production/files/2017- 06/documents/cylindrospermopsin-support-report-2015.pdf. USEPA. 2015g. "Recommendations for Public Water Systems to Manage Cyanotoxins in Drinking Water EPA 815-R-15-010." US. S. Environmental Protection Agency, Chesapeake Bay Program. https://www.epa.gov/sites/production/files/2017- 06/documents/cyanotoxin-management-drinking-water.pdf. USEPA. 2015h. Watershed Academy Webcast: Case Studies on Implementing Low-Cost Modifications to Improve Nutrient Reduction at Wastewater Treatment Plants.: United States Environmental Protection Agency.

135 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

USEPA. 2016. "Nonpoint Source: Hydromodification and Habitat Alteration." United States Environmental Protection Agency. https://www.epa.gov/nps/nonpoint-source- hydromodification-and-habitat-alteration. USEPA. 2017a. "Nonpoint Source: Wetland/Riparian Management." U. S. Environmental Protection Agency. https://www.epa.gov/nps/nonpoint-source-wetlandriparian- management. USEPA. 2017b. "Quality Assurance Program Plan for the Cyanobacteria Monitoring Collaborative Program ". Chelmsford, MA: U. S. Environmental Protection Agency, Office of Environmental Measurement and Evaluation. https://cyanos.org/wp- content/uploads/2017/04/cmc_qapp_final.pdf. USEPA. 2018a. "Statute and Regulations Addressing Impaired Waters and TMDLs. September 10, 2018." U. S. Environmental Protection Agency. https://www.epa.gov/tmdl/statute- and-regulations-addressing-impaired-waters-and-tmdls. USEPA. 2018b. "What is a Wetland? ." U. S. Environmental Protection Agency. https://www.epa.gov/wetlands/what-wetland. USEPA. 2019a. "Clean Water Act Section 401: State Certification of Water Quality." Washington, D. C.: United States Environmental Protection Agency. https://www.epa.gov/cwa-401/clean-water-act-section-401-state-certification-water- quality. USEPA. 2019b. "Exposure to CyanoHABS." U. S. Environmental Protection Agency. https://www.epa.gov/cyanohabs/exposure-cyanohabs. USEPA. 2019c. "National Pollutant Discharge Elimination System (NPDES) Stormwater Program." U. S. Environmental Protection Agency. https://www.epa.gov/npdes/npdes- stormwater-program

USEPA. 2019d. "Recommendations for Cyanobacteria and Cyanotoxin Monitoring in Recreational Waters EPA 823-R-19-001." https://www.epa.gov/sites/production/files/2019-09/documents/recommend-cyano-rec- water-2019-update.pdf. USEPA. 2019e. "Recommended Human Health Recreational Ambient Water Quality Criteria or Swimming Advisories for Microcystins and Cylindrospermopsin EPA 822-R-19-001." Washington, D. C.: U. S. Environmental Protection Agency, Office of Water, Health and Ecological Criteria Division. USEPA. 2019f. "Sources and Solution https://www.epa.gov/nutrientpollution/sources-and- solutions-stormwater." United States Environmental Protection Agency, accessed August 27, 2019. https://www.epa.gov/nutrientpollution/sources-and-solutions-stormwater. USEPA. 2019g. "The Sources and Solutions: Wastewater and Wastewater Treatment plants." U. S. Environmental Protection Agency. https://www.epa.gov/nutrientpollution/sources- and-solutions-wastewater. USEPA. 2020a. "Elements of a Quality Assurance Project Plan (QAPP) For Collecting, Identifying and Evaluating Existing Scientific Data/Information." U. S. Environmental Protection Agency, Science Advisor Programs. https://www.epa.gov/osa/elements- quality-assurance-project-plan-qapp-collecting-identifying-and-evaluating-existing. USEPA. 2020b. "Quality Assurance Project Plan Development Tool." U. S. Environmental Protection Agency. https://www.epa.gov/quality/quality-assurance-project-plan- development-tool.

136 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

USGS. 2018. "Lakes and reservoirs—Guidelines for study design and sampling." Reston, VA: U. S. Geologic Survey Techniques and Methods 9-A10. http://pubs.er.usgs.gov/publication/tm9A10. Vanderploeg, Henry A., James R. Liebig, Wayne W. Carmichael, Megan A. Agy, Thomas H. Johengen, Gary L. Fahnenstiel, and Thomas F. Nalepa. 2001. "Zebra mussel (Dreissena polymorpha) selective filtration promoted toxic Microcystis blooms in Saginaw Bay (Lake Huron) and Lake Erie." Can. J. Fish. Aquat. Sci 58:1208-1221. doi: 10.1139/cjfas- 58-6-1208. Verhamme, Edward M., Todd M. Redder, Derek A. Schlea, Jeremy Grush, John F. Bratton, and Joseph V. DePinto. 2016. "Development of the Western Lake Erie Ecosystem Model (WLEEM): Application to connect phosphorus loads to cyanobacteria biomass." Journal of Great Lakes Research 42 (6):1193-1205. doi: https://doi.org/10.1016/j.jglr.2016.09.006. Vilmin, Lauriane, José M. Mogollón, Arthur H. W. Beusen, and Alexander F. Bouwman. 2018. "Forms and subannual variability of nitrogen and phosphorus loading to global river networks over the 20th century." Global and Planetary Change 163:67-85. doi: https://doi.org/10.1016/j.gloplacha.2018.02.007. Visser, Petra M, Bas W Ibelings, Myriam Bormans, and Jef Huisman. 2016. "Artificial mixing to control cyanobacterial blooms: a review." Aquatic Ecology 50 (3):423-441. Vlach, B; Barton, Johnson, J and Zachay, M. 2010. Case Study #9: Assessment of source reduction due to phosphorus-free fertilizers. In Stormwater Treatment: Assessment and Maintenance, edited by J. S.; Erickson Gulliver, A. J and Weiss, P. T. Minneapolis, MN: University of Minnesota, St. Anthony Falls Voigt, Brian, Julie Lees, and Jon Erickson. 2015. "An Assessment of the Economic Value of Clean Water in Lake Champlain (Report No. 81)." Grand Isle, VT: Lake Champlain Basin Program. https://www.lcbp.org/publications/assessment-economic-value-clean- water-lake-champlain/. Weatherly, Jack. 2019. "Algal bloom cost Mississippi Coast tourism $4.1 million in June, July." Mississippi Business Journal, MBJ Feature. https://msbusiness.com/2019/10/algal- bloom-cost-mississippi-coast-tourism-4-1-million-in-june-july/. Wehr, John, Robert Sheath, and Patrick Kociolek. 2015. Freshwater Algae of North America: Ecology and Classification. Wetzel, Robert G. . 2001. Limnology: Lake and River Ecosystems. San Diego, CA: Academic Press. Wilde, S. B., T. M. Murphy, C. P. Hope, S. K. Habrun, J. Kempton, A. Birrenkott, F. Wiley, W. W. Bowerman, and A. J. Lewitus. 2005. "Avian vacuolar myelinopathy linked to exotic aquatic plants and a novel cyanobacterial species." Environ Toxicol 20 (3):348-53. doi: 10.1002/tox.20111. Withers, P. J. A., L. May, H. P. Jarvie, P. Jordan, D. Doody, R. H. Foy, M. Bechmann, S. Cooksley, R. Dils, and N. Deal. 2012. "Nutrient emissions to water from septic tank systems in rural catchments: Uncertainties and implications for policy." Environmental Science & Policy 24:71-82. doi: https://doi.org/10.1016/j.envsci.2012.07.023. Wolf, D., W. Georgic, and H. A. Klaiber. 2017. "Reeling in the damages: Harmful algal blooms' impact on Lake Erie's recreational fishing industry." J Environ Manage 199:148-157. doi: 10.1016/j.jenvman.2017.05.031.

137 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Wolf, David, and Henry Klaiber. 2017. "Bloom and bust: Toxic algae's impact on nearby property values." Ecological Economics 135 (c):209-221. Wood, S. A., P. T. Holland, and L. MacKenzie. 2011. "Development of solid phase adsorption toxin tracking (SPATT) for monitoring anatoxin-a and homoanatoxin-a in river water." Chemosphere 82 (6):888-94. doi: 10.1016/j.chemosphere.2010.10.055. Wood, Susie. 2017. "Advice on Benthic Cyanobacteria Health Risks and Commuication Strategies in the Southland Region. Report No. 375." Cawthron Institute. https://envirolink.govt.nz/assets/Envirolink/Reports/1781-ESRC169-ADVICE-ON- BENTHIC-CYANOBACTERIA-HEALTH-RISKS-AND-COMMUNICATION- STRATEGIES-IN-THE-SOUTHLAND-REGION.pdf. Wood, Susie, Ian Hawes, Graham McBride, Penny Truman, and Daniel Dietrich. 2015. "Advice to Inform the Development of a Benthic Cyanobacteria Attribute. Report No. 2752." https://www.mfe.govt.nz/sites/default/files/media/Fresh%20water/development-of-a- benthic-cyanobacteria-attribute.pdf. Wu, Di, Ruopu Li, Feiyang Zhang, and Jia Liu. 2019. "A review on drone-based harmful algae blooms monitoring." Environmental Monitoring and Assessment 191. doi: 10.1007/s10661-019-7365-8. Yan, X., X. Xu, M. Ji, Z. Zhang, M. Wang, S. Wu, G. Wang, C. Zhang, and H. Liu. 2019. "Cyanobacteria blooms: A neglected facilitator of CH(4) production in eutrophic lakes." Sci Total Environ 651 (Pt 1):466-474. doi: 10.1016/j.scitotenv.2018.09.197. Yeager, Nicole, and Adam Carpenter. 2019. "State approaches to addressing cyanotoxins in drinking water." AWWA Water Science 1 (1):e1121. doi: 10.1002/aws2.1121. Young, C. Edwin. 1984. "PERCEIVED WATER QUALITY AND THE VALUE OF SEASONAL HOMES1." JAWRA Journal of the American Water Resources Association 20 (2):163-166. doi: 10.1111/j.1752-1688.1984.tb04666.x. Zamyadi, A., L. Ho, G. Newcombe, H. Bustamante, and M. Prévost. 2012. "Fate of toxic cyanobacterial cells and disinfection by-products formation after chlorination." Water Res 46 (5):1524-35. doi: 10.1016/j.watres.2011.06.029. Zilliges, Yvonne, Jan-Christoph Kehr, Sven Meissner, Keishi Ishida, Stefan Mikkat, Martin Hagemann, Aaron Kaplan, Thomas Börner, and Elke Dittmann. 2011. "The Cyanobacterial Hepatotoxin Microcystin Binds to Proteins and Increases the Fitness of Microcystis under Oxidative Stress Conditions." PLOS ONE 6 (3):e17615. doi: 10.1371/journal.pone.0017615. Zimba, P V, L Khoo, P S Gaunt, S Brittain, and W W Carmichael. 2001. "Confirmation of catfish, Ictalurus punctatus (Rafinesque), mortality from Microcystis toxins." Journal of Fish Diseases 24 (1):41-47. doi: 10.1046/j.1365-2761.2001.00273.x. Zimba, P. V., I. S. Huang, D. Gutierrez, W. Shin, M. S. Bennett, and R. E. Triemer. 2017. "Euglenophycin is produced in at least six species of euglenoid algae and six of seven strains of Euglena sanguinea." Harmful Algae 63:79-84. doi: 10.1016/j.hal.2017.01.010. Zuo, Jun, Liting Chen, Kun Shan, Lili Hu, Lirong Song, and Nanqin Gan. 2018. "Assessment of different mcy genes for detecting the toxic to non-toxic Microcystis ratio in the field by multiplex qPCR." Journal of Oceanology and Limnology 36 (4):1132-1144. doi: 10.1007/s00343-019-7186-1.

138 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

139 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

VISUAL GUIDE TO HARMFUL CYANOBACTERIA

Visual Guide to Common Harmful Cyanobacteria - ITRC

Cover: Microphotograph showing Dolichospermum spiroides (Photo: Ann St. Amand)

140 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020 Visual Guide to Common Harmful

Cyanobacteria

Ann St. Amand, Ph.D., CLP, PhycoTech, ITRC, HCB Team

141 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Table of Contents

A-1 Introduction...... 7

A-2 Glossary ...... 7

A-3 Cyanobacterial Blooms: Field and Microscopic Images ...... 9

Microcystis aeruginosa Microcystis viridis Dolichospermum (Anabaena) lemmermannii Dolichospermum (Anabaena) mendotae Aphanizomenon flos-aquae Aphanizomenon gracile Woronichinia (Coelosphaerium) naegeliana Gloeotrichia echinulata Nodularia spumigena Planktothrix agardhii/prolifica Raphidiopsis raciborskii Microseira (Lyngbya/Plectonema) wollei

A-4 Cyanobacteria Which Produce Toxins or Tastes/Odors: Field and Microscopic Images .....39

Microcystis wesenbergii Cuspidothrix issatschenkoi Chrysosporum ovalisporum Dolichospermum circinale Dolichospermum crassa Dolichospermum planctonicum Limnoraphis birgei Sphaerospermopsis torques-reginae Trichodesmium lacustre

A-5 Non-toxic Surface Algal Blooms: Field and Microscopic Images ...... 48

Chlorophyte/Green Algae Rooted Plants Floating Macrophytes Floating Ferns Euglenoids

A-6 References...... 60

142 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Acknowledgments

The author thanks Barry Rosen, Ken Wagner and Andrew Chapman for their contributions. We also thank the numerous photograph contributors who are acknowledged in the captions of the figures. All photographs were used with written permission from the respective photographers.

143 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Visual Guide to Harmful Cyanobacteria

A-1 Introduction

Cyanobacteria, also known as blue-green algae, are a group of microorganisms that live in freshwater and marine habitats throughout the world. Several cyanobacterial species have the ability to produce cyanotoxins, which pose a threat to human health, especially for those who directly consume water and fish taken from a water body that is experiencing a high concentration of cyanobacteria, commonly called an algae bloom. Technically, cyanobacteria are bacteria; however, the names “algae bloom” and “harmful algae bloom (HAB)” have persisted for many decades. In this document, we specifically refer to blooms composed of cyanobacteria as 'harmful cyanobacteria blooms' (HCBs). HCBs typically forms under the correct environmental conditions, such as the abundance of nutrients, stability of the water column, ample light, and warm temperatures for the cyanobacteria. Most bloom-forming cyanobacteria also regulate their buoyance and can optimize their position the water column and float to the surface, although wind can disrupt this process and allow massive accumulations of organisms on the leeward shoreline of a water body. Drinking water and fish associated with these blooms can contain a potent dose of cyanotoxins that are known to damage the liver (hepatotoxins) and the nervous system (neurotoxins).

Warming global temperatures may exacerbate the issue of cyanobacterial blooms. One reason is that they proliferate at very warm water temperatures and are more tolerance of these warmer conditions than their competitors, such as the green algae. In addition, warming temperatures are creating a longer “growing period”, the length of time when a water body above the temperature threshold that favors cyanobacteria.

In an effort to help users develop an awareness of what a potential algal bloom looks like in the field and to distinguish HCBs from non-harmful blooms, this guide illustrates both the appearance of typical cyanobacteria and non-cyanobacteria blooms. Many of the organisms are microscopic and require the use microscope to correctly determine the type of bloom that is present. Included in this guide are microscopic images that illustrate many of the most common bloom formers and others that are known to be a nuisance or produce toxins that are not an obvious surface bloom forming organism.

A-2 Glossary

• akinete - a mature resting cell

• pro-akinete - immature akinete cell

• aerotope - gas vesicle

• heterocyte (heterocyst) - a specialized cyanobacteria cell that is capable of fixing nitrogen

144 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

• bright field – Unenhanced Image

• BLE - blue light excitation

• GLE - green light excitation

• N - Nomarski

• P - Phase

• intercalary - mid-filament location

• terminal - end of filament location

• T&O - taste & odor compounds

• trichomes - cells arranged into more or less linear physiological entities, with or without a diversity of cell types. Straight, twisted or flexuous.

• sheath – polysaccharide based, can be slimy mucilaginous coatings or single or layered sheaths external to the trichome or cells

• filament – trichome plus Sheath

• heteropolar – terminals cells with a different morphology from cells at the other end of the trichome or from central cells in the trichome

145 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

A-3 Cyanobacterial Blooms: Field Images and Microscopic Images

When approaching a water bloom, caution and safety procedures should be used to prevent direct contact with the bloom because some cyanotoxins can be absorbed through the skin or are aerosolized into the surrounding air. These field photos illustrate the color, “texture” and general appearance of water blooms, both harmful and harmless, including nuisance blooms of green algae, certain floating plants and other known blooms that may be encountered.

Figure 1 : Cyanobacteria, Dolichospermum lemmermannii, (Photo: Ann St. Amand Stoney Lake, Michigan)

Figure 2: Cyanobacteria, Dolichospermum lemmermannii, (Photo: Ann St. Amand)

146 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Microcystis aeruginosa Bloom Images.

Figure 3: Cyanobacteria, Microcystis aeruginosa, (Photo: Ann St. Amand Orlando, Florida)

Figure 5: Cyanobacteria, Microcystis aeruginosa, (Photo: Andrew Chapman, Florida)

Figure 4: Cyanobacteria, Microcystis aeruginosa, (Photo: Ann St. Amand Orlando, Florida)

147 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 6 Microcystis aeruginosa (Photo: Elizabeth Fabri Smith, Central Park Lake, KS)

148 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 7 Microcystis aeruginosa (Photo: Elizabeth Fabri Smith, Central Park Lake, KS)

149 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 8 Microcystis aeruginosa (Photo: Elizabeth Fabri Smith, Marion Reservoir, KS)

150 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 9 Microcystis aeruginosa (Photo: Elizabeth Fabri Smith, Marion Reservoir, KS)

151 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 10 Microcystis aeruginosa (Photo: Elizabeth Fabri Smith, Marion Reservoir, KS)

152 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Microcystis aeruginosa – Description and Microscopic Images

Description: Cells spherical or (after division) hemispherical, with homogeneous, bluegreen, greyish or yellowish content. The cells have numerous aerotopes (gas vesicles), especially in older colonies. – Cells are typically imbedded in a gelatinous matrix, and free floating. Colonies can be large enough to see without a microscope, and are amorphous, irregular, and sometimes net-like or calthrate... Several strains produce microcystins, a family of compounds that are hepatotoxins and this species is also known to produce the taste and odor compound pcylocitral. Very common as free floating in the plankton of freshwater, more or less eutrophic lakes and reservoirs (often forming heavy water blooms). This genus is distinguished from Aphanocapsa by the ability to form aerotopes.

Secondary Compounds: Toxin, Taste and Odor Producer

Growth Habit: Forms scums in calm weather, can look “chunky” in the water. There is some evidence that at least 5 species of Microcystis are all one species, however, we are treating them as separate species (Otsuka et al., 2001). Colonies often dissociate in Lugol’s iodine or as the bloom degrades, leaving numerous single cells.

Figure 11: Cyanobacteria, Microcystis aeruginosa, brightfield (Photo: Ann St. Amand)

Figure 12: Cyanobacteria, Microcystis aeruginosa, brightfield (Photo: Ann St. Amand)

Figure 112: Cyanobacteria, Microcystis aeruginosa, brightfield (Photo: Ann St. Amand)

153 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Microcystis viridis – Bloom Images

Figure 13: Cyanobacteria, Microcystis viridis, brightfield (Photo: Ann St. Amand, Paw Paw Lake, Michigan)

Figure 14: Cyanobacteria, Microcystis viridis, brightfield (Photo: Ann St. Amand, Paw Paw Lake, Michigan) Figure 15: Cyanobacteria, Microcystis viridis, brightfield (Photo: Ann St. Amand, Paw Paw Lake, Michigan)

154 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Microcystis viridis - Description and Microscopic Images

Description: Cells spherical or (after division) hemispherical, with homogeneous, bluegreen, greyish or yellowish content. The cells have numerous aerotopes (gas vesicles), especially in older colonies. – Cells are typically imbedded in a gelatinous matrix in “packets”, and free floating. Colonies can be large enough to see without a microscope, and are amorphous, irregular, and sometimes net-like. Several strains produce microcystin, a family of compounds that are hepatotoxins. Free floating in the plankton of freshwater, more or less eutrophic lakes and reservoirs (often forming heavy water blooms). This genus is distinguished from Aphanocapsa by ability to form aerotopes, and distinguished from M. aeruginosa by the way cells are in subgroups or packets.

Secondary Compounds: Toxin, Taste and Odor Producer

Growth Habit: Forms scums in calm weather, can look “chunky” in the water or be evenly distributed in turbid circumstances. Seems to often co-occur with Limnoraphis.

Figure 16: Cyanobacteria, Microcystis viridis, phase (Photo: Figure 17: Cyanobacteria, Microcystis viridis, brightfield Ann St. Amand) (Photo: Ann St. Amand)

155 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Dolichospermum (Anabaena ) lemmermannii – Bloom Images

Figure 18: Cyanobacteria, Dolichospermum lemmermannii, (Photo: Ann St. Amand, Paw Paw Lake, Michigan

Figure 20: Cyanobacteria, Dolichospermum lemmermannii, Figure 19: Cyanobacteria, Dolichospermum (Photo: Ann St. Amand, Stoney Lake, Michigan lemmermannii, (Photo: Ann St. Amand, Little Paw Paw

Lake, Michigan

156 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Dolichospermum (Anabaena) lemmermannii – Description and Microscopic Images

Description: Gas vesicles occur obligatorily in cells in vegetative phase. They are joined into irregular aerotopes (sooner “gas vesicles”) over the whole cell volume; aerotopes are recognizable in cells under optical microscope. Heterocytes arise intercalarly, solitary. Akinetes develop paraheterocytically (in the middle of filaments), heterocytes adjacent to or in between akinetes. Often forms the pattern of akinete-heterocyte-akinete. Akinetes often arise after fusion of two or few neighboring vegetative cells. The ripe akinetes are usually three or more- times larger than vegetative cells. Planktic in vegetative state, never form sessile mats on the substrate. The filaments in small, contorted clusters with akientes clustered in center of colony. Protozoans (Vorticella) often attached to colonies.

Secondary Compounds: Toxin, Taste and Odor Producer

Growth Habit: Forms scums in calm weather, can look like blue-green, cyan or pink paint on the water surface or on substrates around the shoreline.

Figure 22: Cyanobacteria, Dolichospermum lemmermannii, brightfield (Photo: Barry Rosen)

Figure 21: Cyanobacteria, Dolichospermum lemmermannii, nomarski (Photo: Ann St. Amand

157 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Dolichospermum (Anabaena) mendotae – Bloom Images

Figure 23: Cyanobacteria, Dolichospermum mendotae (Photo: Ann St. Amand, Lake Monona, Wisconsin)

Figure 25: Cyanobacteria, Dolichospermum mendotae

Figure 24: Cyanobacteria, Dolichospermum mendotae (Photo: Ann St. Amand, Lake Monona, Wisconsin) (Photo: Ann St. Amand, Lake Monona, Wisconsin)

158 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Dolichospermum (Anabaena) mendotae – Description and Microscopic Images

Description: Gas vesicles occur obligatorily in cells in vegetative phase. They are joined into irregular aerotopes (sooner “gas vesicles”) over the whole cell volume; aerotopes are recognizable in cells under optical microscope. Heterocytes arise intercalarly, solitary. Akinetes develop paraheterocytically (in the middle of filaments), heterocytes distant from (not next to) akinetes. Akinetes often arise after fusion of two or few neighboring vegetative cells. The ripe akinetes are usually three or more-times larger than vegetative cells. Planktic in vegetative state, never form sessile mats on the substrate. The filaments in small, contorted clusters, with akinetes clustered multiple places in the colonies.

Secondary Compounds: Toxin, Taste and Odor Producer

Growth Habit: Forms scums in calm weather, can look like blue-green, cyan or pink paint on the water surface or on substrates around the shoreline.

Figure 26: Cyanobacteria, Dolichospermum mendotae, Phase (Photo: Ann St. Amand) Figure 27: Cyanobacteria, Dolichospermum mendotae, Brightfield (Photo: Ann St. Amand)

159 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Aphanizomenon flos-aquae – Bloom images

Figure 28: Cyanobacteria, Aphanizomenon flos-aquae (Photo: Ann St. Amand, Wisconsin)

Figure 29: Cyanobacteria, Aphanizomenon flos-aquae (Photo: Figure 30: Cyanobacteria, Aphanizomenon flos-aquae Jacob Kann, Klamath Lake, Oregon) (Photo: Jacob Kann, Klamath Lake, Oregon)

160 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Aphanizomenon flos-aquae – Description and Microscopic Images

Description: Filaments free-floating, joined into grass clipping like flakes, microscopic or macroscopic (up to 2 cm long) colonies with trichomes oriented in parallel; trichomes straight, cylindrical, always without firm sheaths, trichomes uniseriate, in the middle part usually cylindrical, isopolar, with distinctly elongated and in older trichomes, vacuolized cells at the ends, with the apical cells long, cylindrical and hyaline (at the end rounded or obtuse), with 1-3 distant, intercalary developed heterocytes, which are localized subsymmetrically at the fully developed trichomes (shifted to one end of a trichome). Vegetative cells cylindrical or barrel-shaped, more or less isodiametrical or slightly shorter or longer than wide, pale blue-green or blue-green, usually with aerotopes. Heterocytes barrel-shaped or cylindrical with rounded or obtuse ends, which can completely disappear under special conditions (under high N-content). Akinetes rarely spherical or widely oval, usually oval to long, cylindrical with rounded ends, developing paraheterocytically, solitary or in short rows (in 2 or 3), close to heterocytes or slightly distant from them, usually in asymmetrical position in a trichome. Planktonic, sometimes forming characteristic water blooms, A. flos-aquae is important in managed fish ponds and in lakes; mainly are distributed in eutrophic systems.

Secondary Compounds: Toxin, Taste and Odor Producer

Growth Habit: Forms scums in calm weather, can look like “grass flakes” in the water.

Figure 32: Cyanobacteria, Aphanizomenon flosaquae, brightfield (Photos: Ann St. Amand)

Figure 31: Cyanobacteria, Aphanizomenon flos-aquae, (Photos: top, nomarki-Barry Rosen, middle, phase/bottom, brightfield-Ann St. Amand)

161 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Aphanizomenon gracile – Description and Microscopic Images

Description: Filaments free-floating, NOT joined into grass clipping like flakes, microscopic or macroscopic (up to 2 cm long) colonies with trichomes oriented in parallel; trichomes straight, cylindrical, always without firm sheaths, trichomes uniseriate, in the middle part usually cylindrical, isopolar, with distinctly elongated and in older trichomes, vacuolized cells at the ends, with the apical cells long, cylindrical and hyaline (at the end rounded or obtuse), with 1-3 distant, intercalary developed heterocytes, which are localized subsymmetrically at the fully developed trichomes (shifted to one end of a trichome). Vegetative cells cylindrical or barrel-shaped, more or less isodiametrical or slightly shorter or longer than wide, pale blue-green or blue-green, usually with aerotopes. Heterocytes barrel-shaped or cylindrical with rounded or obtuse ends, which can completely disappear under special conditions (under high N-content). Akinetes rarely spherical or widely oval, usually oval to long, cylindrical with rounded ends, developing paraheterocytically, solitary or in short rows (in 2 or 3), close to heterocytes or slightly distant from them, usually in asymmetrical position in a trichome. Planktonic, sometimes forming characteristic water blooms.

Secondary Compounds: Toxin, Taste and Odor Producer

Growth Habit: Does not from “grass flakes” in the water.

Figure 33: Cyanobacteria, Aphanizomenon gracile, phase (Photo: Ann St. Amand)

162 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 35: Cyanobacteria, Aphanizomenon gracile, phase (Photo: Ann St. Amand)

Figure 34: Cyanobacteria, Aphanizomenon gracile, phase (Photo: Ann St. Amand)

Figure 36: Cyanobacteria, Aphanizomenon gracile, Phase (Photo: Ann St. Amand)

Figure 37: Cyanobacteria, Aphanizomenon gracile, akinete and pro-akinete, phase (Photos top/bottom: Ann

St. Amand)

163 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Woronichinia (Coelosphaerium) naegeliana – Bloom Images

Figure 38: Cyanobacteria, Woronichinia naegeliana. (Photo: PhycoTech, Kalamazoo County, Michigan)

Figure 39: Cyanobacteria, Woronichinia naegeliana (Photo: Linda Green, University of Rhode Island) Figure 40: Cyanobacteria,

Woronichinia naegeliana (Photo: Ann

St. Amand, Kalamazoo County,

Michigan)

164 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Woronichinia (Coelosphaerium) naegeliana - Description and Microscopic Images

Description: Colonial; colonies microscopic, spherical to irregularly oval, usually composed from subcolonies, free living (plankton, metaphyton), with narrow enveloping mucilaginous layer. Within colonies is developed a system of parallel and radially oriented tube-like stalks,+/- originating all from the center of a colony which are difficult to see in healthy colonies. Cells radially elongated, joined to the ends of stalks, widely oval or slightly obovoid, in old colonies usually very densely, radially agglomerated in the peripheral layer. Cells often appear as “doubles.” Cells pale blue-green or yellowish, with aerotopes.

Secondary Compounds: Toxin, Taste and Odor Producer

Growth Habit: Forms scums in calm weather. Colonies often look like “gumdrops” under the microscope. Colonies often dissociate in Lugol’s iodine or as the bloom degrades often leaving numerous single or doublets of cells.

Figure 42: Cyanobacteria, Woronichinia naegeliana, Nomarksi (Photo: Barry Rosen)

Figure 41: Cyanobacteria, Woronichinia naegeliana Brightfield (Photos: Ann St. Amand)

165 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Gloeotrichia echinulata - Bloom Images

Figure 43: Cyanobacteria, Gloeotrichia echinulata (Photo: Midge Eliassen, New Hampshire)

Figure 44: Cyanobacteria, Gloeotrichia echinulata (Photo: Figure 45: Cyanobacteria, Gloeotrichia echinulata (Photo: Midge Eliassen, New Hampshire) Midge Eliassen, New Hampshire)

166 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Gloeotrichia echinulate - Description and Microscopic Images

Description: Filamentous-colonial; trichomes heteropolar with basal heterocytes and apical hair-like ends with own sheaths, united radially into gelatinous, hemispherical or spherical colonies, which are microscopic up to several cm in diam., olive-green, yellow-green, brown or dark blue-blackish. The whole colony enveloped by a fine or firm slime; trichomes always oriented with heterocytes into the center of the colony. Trichomes often have a curved basal sheath that contains the akinete and persists in the sediments. Colonies are joined to the substrate or free floating. The cells contain aerotopes. Often blooms in relatively nutrient poor waters, compared with other scum forming cyanobacteria.

Secondary Compounds: Toxin, Taste and Odor Producer

Growth Habit: Forms scums in calm weather, often looks small balls in the water column.

Figure 48: Cyanobacteria, Gloeotrichia echinulata, grazed, Brightfield (Photo: Ann St. Amand)

Figure 46: Cyanobacteria, Gloeotrichia echinulata, Nomarski (Photo: Barry Rosen )

Figure 47: Cyanobacteria, Gloeotrichia echinulata, Brightfield (Photo: Ann St. Amand)

167 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Nodularia spumigena – Bloom Images

Figure 49: Cyanobacteria, Nodularia spumigena. (Photo: Wayne Wurtzbaugh, Great Salt Lake, UT)

Figure 50: Cyanobacteria, Nodularia spumigena. Brightfield (Photo: Ann St. Amand)

Figure 51: Cyanobacteria, Nodularia spumigena. Phase (Photo: Ann St. Amand)

168 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Nodularia spumigena - Description and Microscopic Images Description: Filamentous; filaments solitary or in groups or clusters, rarely in mats, isopolar, unbranched (without false or true branching), more or less straight, curved, coiled or irregularly spirally coiled with fine, diffluent sheaths of a special two-layered structure (type species), opened at both ends. Trichomes uniseriate, cylindrical, rarely short and slightly attenuated at the ends of developed trichomes, constricted at crosswalls, metameric, with more heterocytes in more or less regular distances from one another. Cells shortly barrelshaped, their length never exceeds the width, with gas vesicles. Cell content yellowish, pale olive-green or blue-green, thylakoids irregularly coiled, spread all over the cell volume, sometimes more gathered in the peripheral layer of cells. Heterocytes of the same shape of cells, sometimes slightly differ in their size (slightly smaller or larger than vegetative cells). Akinetes shortly barrel-shaped (shorter than wide), or spherical, developing apoheterocytic, but often with irregularities. Cells divide crosswise to the trichome axis and grow to original size before the next division, all cells capable of division, without meristematic zones. Reproduction by hormogonia, dissociation of trichomes, and by akinetes. They occur rarely in freshwater reservoirs, mainly in slightly saline or brackish waters, saline and coastal lakes.

Secondary Compounds: Toxin, Taste and Odor Producer

Growth Habit: Forms scums in calm weather, forming huge mats on the lake surface that are difficult to navigate through.

Figure 52: Cyanobacteria, Nodularia spumigena. Brightfield (Photo: Ann St. Amand)

Figure 53: Cyanobacteria, Nodularia spumigena. Phase (Photo: Ann St. Amand)

169 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Planktothrix agardhii/prolifica - Bloom Images

Figure 54: Planktothrix agardhii/prolifica (Photo: Ron Zurawell, Fleeing Horse Lake, CA)

Figure 55: Planktothrix agardhii Figure 56: Planktothrix agardhii/prolifica /prolifica (Photo: Ron Zurawell,

Forker Lake, Canada ) (Photo: Ron Zurawell, Fleeing Horse Lake, CA)

170 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Planktothrix agarghii/ prolifica - Description and Microscopic Images Description: Filaments solitary, rarely in small irregular and easy disintegrating fascicles (groups), more or less straight or slightly waved, isopolar, free living; usually growing without sheath. Trichomes with cylindrical cells, slightly constricted at the crosswalls, sometimes slightly tapering to the ends, to 4 mm long, 3.5-10 _m wide; occasionally with slight movement (trembling). Cells slightly shorter than wide to almost isodiametric, rarely slightly longer than wide, with aerotopes through the whole cell volume (but sometimes without gas vesicles in parts of trichomes); end cells (when fully developed) widely rounded or slightly narrowed and with thickened outer cell wall or with calyptra. Heterocytes and akinetes absent. Mainly in mesotrophic to eutrophic reservoirs (usually lakes), often growing at depth. Can form red blooms under the ice in winter.

Secondary Compounds: Toxin Producer

Growth Habit: Does not tend to form scums, colors ice red in winter blooms.

Figure 57: Cyanobacteria, Planktothrix agardhii, Phase (Photo: Ann St. Amand)

Figure 58: Cyanobacteria, Planktothrix agardhii. Top and Middle, Phase (Photo: Ann St. Amand) , Bottom, Brightfield (Photo: Barry Rosen)

171 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Raphidiopsis raciborskii – Bloom images

Figure 59: Cyanobacteria, Raphidiopsis raciborskii. (Photo: Ann St. Amand, OK)

Figure 60: Cyanobacteria, Raphidiopsis raciborskii.

(Photo: Ann St. Amand, OK ) Figure 61: Cyanobacteria, Raphidiopsis raciborskii. (Photo: Michael Martin, IN)

172 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Raphidiopsis raciborskii – Description and Microscopic Images

Description: Filaments solitary, straight or screw-like coiled, free-floating, slightly narrowed to the both ends, without sheaths; trichomes isopolar. Cells cylindrical, isodiametric or shorter or longer than wide, pale blue-green or yellowish, with aerotopes; end cells (before heterocyte formation) narrowed, conical, bluntly pointed. Heterocytes ovoid or conical, sometimes slightly curved, unipored, terminal; Akinetes oval to cylindrical with rounded ends, developing asymmetrically on a trichome, solitary or in short rows (up to three), slightly distant from the terminal heterocytes, rarely close to heterocytes. Cells divide crosswise (sometimes asymmetrically) and grow more or less into the original size before the next division. Planktonic in eutrophic aquatic basin, but does not form scums. Water is often an olive-brown color. R. raciborskii is a late summer bloomer, and tends to be associated with a lack of zooplankton in the water column.

Secondary Compounds: Toxin Producer

Growth Habit: Does not form scums in calm weather.

Figure 63: Cyanobacteria, Raphidiopsis raciborskii. Straight morphs. Top-Phase, (Photo: Ann St. Amand) Bottom-Nomarksi (Photo: Barry Rosen)

Figure 62: Cyanobacteria, Raphidiopsis raciborskii. Curled and Curled to straight morphs. Top-Phase, Bottom-Epifluoresence, green excitation (Photos: Ann St. Amand)

173 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Microseira (Lyngbya/Plectonema) wollei – Bloom Image and Description

Figure 64: Meicroseira (Lyngbya/Plectonema) wollei. (Photo: Ken Wagner)

Description Filamentous; filaments long, isopolar, solitary or in macroscopic clusters. Always with more or less thick, firm, colorless sheaths, lamellated, open at the apex, obligately and frequently false-branched. Trichomes isopolar, 16-25 um wide, uniseriate, composed of short cylindrical or barrel-like (discoid) cells (always shorter than wide, usually several times), unconstricted at the crosswalls, not attenuated. Cells without aerotopes, sometimes with granular, blue-green, olive-green or grey-blue content; end cells widely rounded, sometimes capitate or with slightly thickened outer cell wall. Heterocytes and akinetes absent. In clear (usually katharobic to oligosaprobic) water basins, springs or creeks, in metaphyton and periphyton.

Secondary Compounds: Toxin Producer

Growth Habit: Mats float to surface in calm weather, forming huge mats on the lake surface that are difficult to navigate through. Very difficult to control.

174 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Microseira (Lyngbya/Plectonema) wollei – Bloom Image

Figure 66: Meicroseira (Lyngbya/Plectonema) wollei. Nomarski (Photo: Ann St. Amand)

Figure 65: Meicroseira (Lyngbya/Plectonema) wollei. Brightfield (Photo: Barry Rosen)

Figure 68: Meicroseira (Lyngbya/Plectonema) wollei. Nomarski (Photo: Ann St. Amand) Figure 67: Meicroseira (Lyngbya/Plectonema) wollei. Nomarksi (Photo: Ann St. Amand)

175 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

A-4 Cyanobacteria Which Produce Toxins or Tastes/Odors: Field and Microscopic Images

The taxa presented in this section tend to appear in assemblages of mixed taxa and not as single taxon blooms.

Figure 69 . Cyanobacteria: Top, Brightfield : Microcystis aeruginosa under low power showing various colony morphologies (Photo: Barry H. Rosen), Bottom, Epifluorscence green excitation: Microcystis aeruginosa, Planktothrix agardhii and Dolichospermum (Photo: Ann St. Amand)

176 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Microcystis wesenbergii

Figure 70: Microcystis wesenbergii, Nomarski. (Photo: Ann St. Amand)

Figure 71: Microcystis wesenbergii, M. viridis. Nomarski. (Photo: Ann St. Amand)

177 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Cuspidothrix issatschenkoi

Figure 72: Cyanobacteria. Cuspidothrix issatschenkoi, Phase. (Photo: Ann St. Amand)

Figure 73: Cyanobacteria. Cuspidothrix issatschenkoi, Phase. Top-Nomarksi (Photo: Barry Rosen), Bottom-Phase (Photo: Ann St. Amand)

178 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Chrysosporum ovalisporum

Figure 74: Cyanobacteria. Chrysosporum ovalisporum, Brightfield. (Photo: Ann St. Amand)

Figure 75: Cyanobacteria. Chrysosporum ovalisporum, Nomarski. (Photo: Ann St. Amand)

179 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Dolichospermum circinale

Figure 76: Cyanobacteria. Dolichospermum circinale, Phase. (Photo: Ann St. Amand)

Figure 77: Cyanobacteria. Dolichospermum circinale, Phase. (Photo: Ann St. Amand)

180 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Dolichospermum crassa

Figure 78: Cyanobacteria. Dolichospermum crassa, Phase. (Photo: Ann St. Amand)

Figure 79: Cyanobacteria. Dolichospermum crassa, Phase. (Photo: Ann St. Amand)

181 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Dolichospermum planctonicum

Figure 80: Cyanobacteria. Dolichospermum planctonicum, Phase. (Photo: Ann St. Amand)

Figure 81: Cyanobacteria. Dolichospermum planctonicum, Phase. (Photo: Ann St. Amand)

182 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Limnoraphis birgei

Figure 82: Cyanobacteria, Limnoraphis birgei, Phase. (Photo: Ann St. Amand)

Figure 838: Cyanobacteria, Limnoraphis birgei, Brightfield. (Photo: Ann St. Amand)

183 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Sphaerospermopsis torques-reginae

Figure 79: Cyanobacteria, Sphaerospermopsis torques-reginae, Left - Nomarski (Photo: Barry H. Rosen), Right- Phase (Photo: Ann St. Amand)

Trichodesmium lacustre

Figure 80: Trichodesmium lacustre

184 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

A-5 Non-toxic Surface Algal Blooms: Field and Microscopic Images

Not all algal blooms are harmful, and some are actually helpful. Algae and other aquatic plants are the base of the food chain in lakes, ponds and rivers. It is often difficult to distinguish a harmful algal bloom from a non-toxic bloom or other aquatic plants.

The following pages contain field and microscopic images of several common non-toxic algae and aquatic plants, including representatives from the following groups:

• Chlorophyte/Green Algae

• Rooted Plants

• Floating Macrophytes

• Floating Ferns

• Euglenoids

185 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Chlorophytes (Green Algae) Mougeotia sp.

Figure 85: Chlorophyte, Mougeotia sp. (Photo: Steve Heiskary, MPCB)

Figure 86: Chlorophyte, Mougeotia sp. (Photo: Steve Heiskary, MPCB)

186 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Cladophora sp.

Figure 93: Chlorophyte, Cladophora sp. (Photo: Ann St. Amand, Carmel, IN)

Figure 95 : Chlorophyte, Cladophora sp. (Photo: Ann St. Amand, Paw Paw River, MI) Figure 94: Chlorophyte, Cladophora sp. Nomarksi (Photo: Ann St. Amand)

187 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Hydrodictyon sp.

Figure 96: Chlorophyte. Hydrodictyon sp., Waternet (Photo: Ken Wagner)

Figure 97: Chlorophyte. Hydrodictyon sp., Waternet, Brightfield (Photo: Ann St. Amand)

188 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Pithora sp.

Figure 112 1: Chlorophyta, Pithora sp., Brightfield (Photo: Ann St. Amand)

Figure 112 3: : Chlorophyta, Pithora sp., Nomarski (Photo: Figure 112 2: : Chlorophyta, Pithora sp., Nomarski (Photo: Ann St. Amand) Ann St. Amand)

189 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Spirogyra sp.

Figure 112 4: Chlorophyta, Spirogyra sp. (Photo: Ken Wagner)

Figure 112 6: Chlorophyta, Spirogyra sp., (Photo: Terri Figure 112 5: Chlorophyta, Spirogyra sp., Brightfield Peters) (Photo: Ann St. Amand)

190 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Rooted Plants Chara sp.

Figure 112 7: Charophyta, Chara sp. (Photo: Ann St. Amand, Berrien County, MI)

Figure 112 9 : Charophyta, Chara sp. (Photo: Ann St. Amand ) Figure 112 8: Charophyta, Chara sp. Brightfield (Photo: Ann St. Amand)

191 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Rooted Macrophytes

Figure 87: Rooted Macrophytes. (Photo: Ann St. Amand, Kalamazoo County, Michigan)

Figure 88: Rooted Macrophytes. (Photo: Ann St. Amand, Kalamazoo County, Michigan)

192 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Floating Macrophytes Duckweed – Lemna sp.

Figure 89: Lemna sp., Duckweed (Photo: Ann St. Amand, Kalamazoo County, Michigan)

193 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 90: Lemna sp., Duckweed (Photo: Ann St. Amand, Kalamazoo County, Michigan)

Watermeal – Wolffia sp.

Figure 91: Wolffia columbiana, Watermeal (Photo: Ann St. Amand, Kalamazoo County, Michigan)

194 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 92: Wolffia columbiana, Watermeal (Photo: Barry Rosen)

Floating Ferns Water Fern – Azolla sp.

195 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 99: Azolla sp., Water fern (Photo: Bob Kirschner, Chicago Botanic Garden)

Figure 100: Azolla sp., Water fern Left-Leaves, Right- Anabaena azollae (Photos: Ann St. Amand)

Euglenas

196 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 97: Euglenophyta, Euglena sp. (Photo: Ann St. Amand, Berrien County, MI)

Figure 98: Euglenophyta, Euglena sp., Nomarksi (Photo: Ann St. Amand, Berrien County, MI)

197 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

A-6 References

Wacklin, P., Hoffmann, L. & Komárek, J. (2009). Nomenclatural validation of the genetically revised cyanobacterial genus Dolichospermum (Ralfs ex Bornet et Flahault) comb. nova. Fottea 9(1): 59-64.

Komárek, J., Kastovsky, J., Mares, J. & Johansen, J.R. (2014). Taxonomic classification of cyanoprokaryotes (cyanobacterial genera) 2014, using a polyphasic approach. Preslia 86: 295-335.

Komárek, J. (2013). Cyanoprokaryota: III. Teil: Heterocystous genera. Vol. 19 (3) pp. [i]-xviii, [1]-1130. Süsswasserflora von Mitteleuropa. Heidelberg: Springer Spektrum.

Komárek, J., and Anagnostidis, K. 2001. Cyanoprokaryota I. Teil. Chroococcales. In: H. Ettl, G. Gartner, H. Heynig & D. Mollenhauer (eds.), Susswasserflora von Mitteleuropa, 19(1). G. Fischer, Jena. 548 pp.

Komárek, J., and Anagnostidis, K. 2005. Cyanoprokaryota II. Teil. Oscillatoriales. In: B. Büdel, G. Gärtner, L. Krienitz & M. Schagerl (eds.), Susswasserflora von Mitteleuropa, 19(2). Elsevier, Heidelberg. 759 pp.

Otsuka,, S., Suda, S., Shibata, S., Oyaizu, H., Matsumoto, S., and Watanabe, M. 2001. A proposal for the unification of five species of the cyanobacterial genus Microcystis Ku$tzing ex Lemmermann 1907 under the Rules of the Bacteriological Code International Journal of Systematic and Evolutionary Microbiology, 51, 873–879

Wehr, J.D., Sheath, R.G. and Kociolek, J.P. 2015. Freshwater Algae of North America. 2nd Edition. Academic Press, Boston. 1066 pages.

198 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1 NORTH AMERICAN LAKE MANAGEMENT SOCIETY RISK 2 COMMUNICATION SURVEY

3 The North America Lake Management Society (NALMS), in conjunction with the ITRC HCB 4 team, distributed a survey using the Survey Monkey platform to gain insight into the 5 effectiveness of HCB notification/outreach materials used to inform lake users of HCBs in 6 different regions of the United States. The effectiveness of HCB education and outreach 7 materials is unknown, particularly as the effectiveness relates to the individual’s age, residency 8 with respect to a lake, or residency within a country. The survey was designed to get information 9 on this subject to help decision makers better communicate with people on issues related to 10 HCBs. Specifically, the survey focused on how people receive information related to HCBs now 11 and their preferred way to receive future information. This survey was distributed via NALMs to 12 its membership. The survey was then shared by NALMs members to different state agencies and 13 other groups with interests in lakes.

14 The survey contained questions on several topics:

15 • Information on demographics of the respondent

16 • Information on a lake, and the activities undertaken at the lake

17 • Knowledge of HCBs

18 • Information received regarding HCBs

19 • Actions taken in response to information received regarding an HCB.

20 The results of the survey generally showed that . . . . (placeholder for data summary paragraphs 21 once it is available).

22 You can find more information on the ITRC NALMS Notification Survey at 23 https://www.nalms.org/cyanosurvey2020/.

199 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

24 MANAGEMENT STRATEGY OVERVIEWS

25 C.1 Introduction

26 This section provides descriptions of management strategies presented in Table 6-1, evaluated 27 for effectiveness, advantages, limitations, relative cost, and regulatory and policy considerations. 28 Each fact sheet can stand alone and is intended to provide guidance and technical background to 29 evaluate the use of a given management strategy in an HCB-affected water body.

30 There is a summary of cost information for some of the management strategies included in this 31 appendix

32 We necessarily limited this review to methods that are used in contemporary settings and have 33 some support from peer reviewed literature. Some of the methods that were considered, but are 34 not reviewed here, are included at the end of this Appendix.

200 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

37 ACIDIFICATION

38 In-lake Prevention Strategy Limited Supporting Field Data

39 The acidification of freshwater aquatic systems either by surface discharge or by precipitation 40 has been noted as an issue of increasing environmental concern (Graham, Arancibia-Avila, and 41 Graham 1996). In normal freshwater systems, a normal pH is usually between 6.5 and 9.0 42 (USEPA 1986). Aquatic organisms, including cyanobacteria that may cause HCBs, exist in a 43 variety of environments over wide pH ranges. However, these organisms have a tolerance which, 44 once a shift occurs, may impact their ability to function and survive. Ecologists who have 45 surveyed acidified lakes noticed that cyanobacteria are often absent in benthic habitats where the 46 pH is less than 4.0 and mildly acidic lakes with pH ranges of 5.0 to 6.0 (Brock 1973). 47 Researchers proposed that shifting the pH into an acidic environment could control or eliminate 48 cyanobacterial blooms (Klemer et al. 1996). In a recent review (Triest, Stiers, and Van Onsem 49 2016), data from mesocosm experiments indicated that the addition of CO2 to a pH around 7.0 50 kept cyanobacterial biomass low [Teissier et al. 2011 in (Triest, Stiers, and Van Onsem 2016)]. 51 Similarly, following biomanipulation of Lake Vesijärvi, Keto and Tallberg (2000) suggested low 52 pH may have prevented cyanobacterial dominance and Peretyatko et al. (2012) lists low pH as 53 one parameter that limits cyanobacterial growth in hypereutrophic ponds.

54 Evidence of acidification occurring naturally has been reported previously. Planktonic species of 55 cyanobacteria disappeared from the epilimnion (upper layer of water) in Little Rock Lake, 56 Wisconsin as the pH fell to 5.2 (Klemer et al. 1996). In controlled studies, blooms in 57 experimental lakes remained dominated by cyanobacteria until the pH dropped below 5.2, at 58 which point filamentous green algae became most abundant for a limited time (Turner et al. 59 1995). This pattern of acidification does not seem to be universal however, as succession in the 60 same lake showed the shift of Anabaena spp. (Dolichospermum spp.) and Lyngbya spp. to 61 colonial species of Merismopedia and Chroococcus. This shift in species is consistent with other 62 field observations that low pH seems to select for cyanobacteria that do not regulate their 63 buoyancy by gas vesicles. As pH was decreased from 5.9 to 5.1, the abundance of cyanobacteria 64 that form gas vesicles decreased, while abundance of those without gas vesicles increased 65 (Findlay and Kasian 1986).

66 There is limited applied data (see Teissier et al. 2011 mesocosm results above) to suggest that 67 artificially acidifying water will prevent or control an ongoing HCB. Experimental acidification 68 has been studied in a number of benchtop and laboratory assays which utilized bubbled CO2 to 69 artificially lower the pH while the cells were growing under optimal conditions. These studies 70 had results similar to the field data above, i.e., that growth of targeted species of cyanobacteria 71 were adversely affected starting at pH <6.0 (Wang et al. 2011). 72 73 While the exact method of action is not known, acidification could physiologically inhibit 74 cyanobacteria growth or could adversely affect any number of biological processes the 75 cyanobacteria use. Some laboratory observation data has highlighted that low pH inhibits 76 important cellular functions such as CO2 concentrating mechanisms. It has also been observed 77 that low pH causes cyanobacterial cells to expend high levels of energy to maintain optimal 201 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

78 intracellular pH range for metabolic processes, and low pH causes the cell to build up carbonic 79 acid which can interfere with photosynthesis (Mangan et al. 2016).

EFFECTIVENESS NATURE OF HCB • Water body type: lake/reservoir • Cyanobacteria species that use gas vesicles • Surface area: small to regulate buoyancy • Unknown interaction with cyanotoxins • Effects on all aquatic species, including non- target organisms • Prevention strategy 80

ADVANTAGES LIMITATIONS • Field observations note that potentially • Few full-scale studies (on entire ecosystem problematic cyanobacteria species are absent impact) on artificially lowering pH in acidified environments • Limited field data noted that while gas • Limited experimental data show that vesicle forming species died, non-gas artificially lowering pH causes gas vesicle- vesicle species were able to grow in their dominated bloom forming cyanobacteria to place die • Laboratory studies that bubbled CO2 were conducted on pure cultures under optimal conditions 81 COST ANALYSIS

82 Adding CO2 to a water body will not necessarily shift the pH adequately, as pH depends on a 83 variety of ambient conditions. Previous studies have pumped CO2 into water, using tanks of 84 liquid CO2 which can be readily acquired from various vendors. The cost of this method will 85 depend partly on whether the multiple bubble lines spanning a lake are derived from one tank or 86 from multiple tanks. Multiple tanks can be spaced roughly 10 acres apart with individual 87 bubblers.

88 Table C-1. Acidification cost analysis per growing season.

ITEM RELATIVE COST PER GROWING SEASON Material $$ Personal Protective Equipment $ Equipment $$ Machinery $ Tools $ Labor $ O&M Costs $ Delivery $ OVERALL $$

202 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

89 REGULATORY AND POLICY CONSIDERATIONS

90 Implementation of acidification equipment may require installation of temporary tubing as well 91 as investment in infrastructure to maintain and support the tools and supplies needed to maintain 92 and monitor the supply of the bubbling system. Monitoring lake pH should be embedded in the 93 treatment as there is no known quantified relationship between volume of gas added and the 94 response of the small lakes. Off target effects are possible, affecting fish and other aquatic life 95 that may be impacted by the sudden shift in pH. Various regulatory entities may prohibit shifts in 96 pH more than 1 unit above or below typical background levels to minimize off target effects of 97 treatment. Applicable State Water Quality Criteria must also be considered.

98 REFERENCES

99 Brock, Thomas D. 1973. "Lower pH Limit for the Existence of Blue-Green Algae: Evolutionary and Ecological 100 Implications." Science 179 (4072):480-483. doi: 10.1126/science.179.4072.480. 101 Findlay, D. L., and S. E. M. Kasian. 1986. "Phytoplankton community responses to acidification of lake 223, 102 experimental lakes area, northwestern Ontario." Water, Air, and Soil Pollution 30 (3):719-726. doi: 103 10.1007/BF00303337. 104 Graham, James M., Patricia Arancibia-Avila, and Linda E. Graham. 1996. "Effects of pH and selected metals on 105 growth of the filamentous green alga Mougeotia under acidic conditions." Limnology and Oceanography 106 41 (2):263-270. doi: 10.4319/lo.1996.41.2.0263. 107 Keto, Juha, and Petra Tallberg. 2000. "The recovery of Vesijärvi, a lake in southern Finland: Water quality and 108 phytoplankton interpretations." Boreal Environmental Research 5. 109 Klemer, Andrew R., John J. Cullen, Michael T. Mageau, Kathryn M. Hanson, and Richard A. Sundell. 1996. 110 "CYANOBACTERIAL BUOYANCY REGULATION: THE PARADOXICAL ROLES OF CARBON1." 111 Journal of Phycology 32 (1):47-53. doi: 10.1111/j.0022-3646.1996.00047.x. 112 Mangan, N. M., A. Flamholz, R. D. Hood, R. Milo, and D. F. Savage. 2016. "pH determines the energetic efficiency 113 of the cyanobacterial CO2 concentrating mechanism." Proc Natl Acad Sci U S A 113 (36):E5354-62. doi: 114 10.1073/pnas.1525145113. 115 Peretyatko, Anatoly, Samuel Teissier, Sylvia De Backer, and Ludwig Triest. 2012. "Classification trees as a tool for 116 predicting cyanobacterial blooms." Hydrobiologia 689 (1):131-146. doi: 10.1007/s10750-011-0803-4. 117 Triest, Ludwig, Iris Stiers, and Stijn Van Onsem. 2016. "Biomanipulation as a nature-based solution to reduce 118 cyanobacterial blooms." Aquatic Ecology 50 (3):461-483. doi: 10.1007/s10452-015-9548-x. 119 Turner, M. A., D. W. Schindler, D. L. Findlay, M. B. Jackson, and G. Gc Robinson. 1995. "Disruption of littoral 120 algal associations by Experimental Lake acidification." Canadian Journal of Fisheries and Aquatic 121 Sciences 52 (10):2238-2250. doi: 10.1139/f95-815b. 122 USEPA. 1986. Quality Criteria for Water, 1986 EPA 440/5-86-001. Washington, D. C.: U. S. Environmental 123 Protection Agency, Office of Water. 124 Wang, X., C. Hao, F. Zhang, C. Feng, and Y. Yang. 2011. "Inhibition of the growth of two blue-green algae species 125 (Microsystis aruginosa and Anabaena spiroides) by acidification treatments using carbon dioxide." 126 Bioresour Technol 102 (10):5742-8. doi: 10.1016/j.biortech.2011.03.015.

127

128 .

203 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

129 BARLEY STRAW

130 In-lake Prevention Strategy Substantial Supporting Field Data

131 Barley straw (Hordeum vulgare) has been used for 45 decades in preventing the growth of 132 cyanobacteria. Initial reports showed widespread success in the United Kingdom, and its use has 133 spread to the U.S. in the past 20 years Sellner and Rensel (2018). Decomposition of barley straw 134 leads to the breakdown of the cell wall which contains lignin and its decomposition produces two 135 types of residues that limit cyanobacterial growth. Some are specific compounds that 136 individually inhibit cyanobacteria, while others yield strong oxidizing agents that rapidly reduce 137 cell viability. For details and examples, please consult the following publications: (Pillinger, 138 Cooper, and Ridge 1994), Ridge and Pillinger (1996), Xiao et al. (2010), Xiao et al. (2014), 139 Matthijs et al. (2012), and Huang et al. (2015).

140 The general procedure is as follows: 1-1.5 months prior to an expected HCB, you can stake or 141 otherwise secure <1 yr. old fungicide-free bales of barley straw into the littoral zone of ponds, 142 lakes, or incoming streams. Bales should be applied at a rate of 7 bales/acre with several bales 143 saved to deploy half-way through the summer. Bales should be re-applied each year thereafter, 144 again saving some bales for mid-summer deployment. Ranges for barley straw treatment of 145 cyanobacteria in other systems are 6-50 mg barley straw/L in longer residence time waters such 146 as lakes or reservoirs (Sellner and Rensel 2018).

EFFECTIVENESS NATURE OF HCB • Water body type: pond, lakes/reservoir, • All HCB types in ponds to estuaries bay/estuary • Singular or repeating HCB • Any surface area or depth • Toxic and non-toxic HCBs • Any trophic state • Prevention strategy • Any mixing regime • Water body uses: recreation, drinking water

147 The technique (7 bales/acre) is effective for most ponds, lakes, reservoirs, and low salinity 148 estuarine areas and is even more effective if enriched with fungi to aid in lignin decomposition 149 (Sellner et al. 2015). There are some concerns for removal of tannins in drinking water facility 150 from decomposing straw. It will not work if applied after the HCB has appeared nor be as 151 effective if the bales are placed in low light or dark areas.

152

153

154

155

156

204 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

ADVANTAGES LIMITATIONS • Effective for most HCBs • Will work on most systems, but very large • Prevents HCBs and therefore any toxin lakes would require significant staff effort accumulations for bale deployment • Used in many areas • Possible open-water obstruction • Cost is low if bales purchased from a • Straw decomposition products include farmer tannins, a concern for removal in drinking • Securing bales along shoreline is easy water facilities • No impact on submersed plants or fish • A small mid-summer bale addition may be required • Some Biological Oxygen Demand (BOD) accompanies straw decomposition, possibly affecting dissolved oxygen levels • Some lake organizations object to bale use due to aesthetics

157

158 Figure 1: Barley straw lining a stream entering an HCB-dominated lake in eastern Maryland (A) 159 and along the shoreline of a brackish lagoon in Chesapeake Bay (B).

160 Figure source: (A) A. Place and (B) K. Sellner. Used with permission.

161 Other similar options: Rice straw inhibits Microcystis aeruginosa in the laboratory (Park et al. 162 2006), was used effectively in Nile River Tilapia ponds (Eladel, Abd-Elhay, and Anees 2019, 163 Shahabuddin et al. 2012), and inhibited Anabaena in laboratory experiments (Eladel et al. 2019). 164 Using lake water in aquaria, (Tomasko, Britt, and Carnevale 2016) reported that dried cypress 165 leaves at 1.51 g/39 L were more inhibitory to cyanobacteria than equal additions of barley straw.

205 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

166 COST ANALYSIS CASE STUDY EXAMPLES

167 Costs for fungicide-free barley straw bales from Williston Lake, Denton, Maryland, 168 farmers is inexpensive relative to retail prices United States: There were 500 barley 169 from landscape or pond supply companies (5-10x straw bales deployed over 67 acres of an 170 higher). Implementation requires labor to secure incoming stream and shoreline of Lake 171 bales in the littoral zone and may require a small Williston during April-May while lake 172 mid-summer bale addition. was partially drained, resulting in the lake remaining free of Microcystis aeruginosa. 173 Table 1: Barley straw cost analysis per growing Microcystin and anatoxin-a 174 season. concentrations were below recreational exposure levels in the first year and then ITEM RELATIVE COST175 PER GROWING absence of the species and toxins in SEASON 176 subsequent years (Sellner et al. 2015). Material $ 177 Ponds, drainage ditches, and lakes, Equipment $ United Kingdom and Ireland: Barley Labor $ 178 straw was effective in reducing O&M Costs -- Oscillatoria agardhii (P. agardhii) from OVERALL $ 179 10,000 filaments/mL to non-detectable levels in a 6-ha lake after 3 weeks 180 exposure; lake managers for 29 other water bodies indicated dramatic 181 REGULATORY AND POLICY cyanobacteria reductions following barley 182 CONSIDERATIONS straw additions (Newman and Barrett 1993). 183 The only limitations for bale deployment are 184 aesthetics (view-sheds) and boating obstructions Potable water reservoir, Aberdeen, 185 if bales are secured in open water. Scotland: Approximately twice/yr barley straw treatment (6-28 g/m3) of a reservoir 186 REFERENCES from 1993-1998 substantially reduced cyanobacteria (Barrett, Littlejohn, and 187 Barrett, P. R. F., J. W. Littlejohn, and J. Curnow. 1999. 188 "Long-term algal control in a reservoir using Curnow 1999). 189 barley straw." Hydrobiologia 415 (0):309-313. 190 doi: 10.1023/A:1003829318450. Derbyshire Reservoir, United Kingdom: 191 Eladel, Hamed, Mohamed Battah, Aida Dawa, Reham Abd- Cyanobacteria were significantly reduced 192 Elhay, and Doaa Anees. 2019. "Effect of rice straw when 50 and 25 g/m3 of barley straw was 193 extracts on growth of two phytoplankton isolated added to a disused United Kingdom water 194 from a fish pond." Journal of Applied Phycology 195 31 (6):3557-3563. doi: 10.1007/s10811-019- supply reservoir (Everall and Lees 1996, 196 01766-0. 1997). 197 Eladel, Hamed Mohamed, Reham Abd-Elhay, and Doaa 198 Anees. 2019. "Effect of Rice Straw Application on Pond, Dublin, Ireland: Barley straw 199 Water Quality and Microalgal Flora in Fish additions (25-50 g/m2) to the pond at the 200 Ponds." Egyptian Journal of Botany 59 (1):171- 201 184. doi: 10.21608/ejbo.2018.4852.1199. Tolka Valley Park, Finglas, Dublin prevented growth of Lyngbya mats (Stack and Zhao 2014). 206 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

202 Everall, N. C., and D. R. Lees. 1996. "The use of barley-straw to control general and blue-green algal growth in a 203 Derbyshire reservoir." Water Research 30 (2):269-276. doi: https://doi.org/10.1016/0043-1354(95)00192- 204 1. 205 Everall, N. C., and D. R. Lees. 1997. "The identification and significance of chemicals released from decomposing 206 barley straw during reservoir algal control." Water Research 31 (3):614-620. doi: 207 https://doi.org/10.1016/S0043-1354(96)00291-6. 208 Huang, Haomin, Xi Xiao, Anas Ghadouani, Jiaping Wu, Zeyu Nie, Cheng Peng, Xinhua Xu, and Jiyan Shi. 2015. 209 "Effects of natural flavonoids on photosynthetic activity and cell integrity in Microcystis aeruginosa." 210 Toxins 7 (1):66-80. doi: 10.3390/toxins7010066. 211 Matthijs, H. C., P. M. Visser, B. Reeze, J. Meeuse, P. C. Slot, G. Wijn, R. Talens, and J. Huisman. 2012. "Selective 212 suppression of harmful cyanobacteria in an entire lake with hydrogen peroxide." Water Res 46 (5):1460- 213 72. doi: 10.1016/j.watres.2011.11.016. 214 Newman, Jonathan, and P. R. F. Barrett. 1993. "Control of Microcystis aeruginosa by decomposing barley straw." 215 Journal of Aquatic Plant Management 31:203-206. 216 Park, M. H., M. S. Han, C. Y. Ahn, H. S. Kim, B. D. Yoon, and H. M. Oh. 2006. "Growth inhibition of bloom- 217 forming cyanobacterium Microcystis aeruginosa by rice straw extract." Lett Appl Microbiol 43 (3):307-12. 218 doi: 10.1111/j.1472-765X.2006.01951.x. 219 Pillinger, J. M., J. A. Cooper, and I. Ridge. 1994. "Role of phenolic compounds in the antialgal activity of barley 220 straw." Journal of Chemical Ecology 20 (7):1557-1569. doi: 10.1007/BF02059880. 221 Ridge, Irene, and J. M. Pillinger. 1996. "Towards understanding the nature of algal inhibitors from barley straw." 222 Hydrobiologia 340 (1):301-305. doi: 10.1007/BF00012772. 223 Sellner, Kevin, Allen Place, Ernest Williams, Yonghui Gao, Elizabeth VanDolah, Michael Paolisso, Holly Bowers, 224 and Shannon Roche. 2015. "Hydraulics and barley straw (Hordeum vulgare) as effective treatment options 225 for a cyanotoxin-impacted lake." Proceedings of the 16th International Conference on Harmful Algae:218- 226 221. 227 Sellner, Kevin, and J. E. Rensel. 2018. "Prevention, Control, and Mitigation of Harmful Algal Bloom Impacts on 228 Fish, Shellfish, and Human Consumers." In Harmful Algal Blooms: A Compendium Desk Reference, edited 229 by Sandra E. Shumway, JoAnn M. Burkholder and Steven L. Morton, 435-492. Wiley-Blackwell. 230 Shahabuddin, A. M., M. Oo, Y. Yi, Dhirendra Thakur, Amrit Bart, and J. Diana. 2012. "Study about the Effect of 231 Rice Straw Mat on Water Quality Parameters, Plankton Production and Mitigation of Clay Turbidity in 232 Earthen Fish Ponds." World Journal of Fish and Marine Sciences 4:577-585. doi: 233 10.5829/idosi.wjfms.2012.04.06.6515. 234 Stack, John, and Yaqian Zhao. 2014. "Performance Assessment of an Integrated Constructed Wetland-Pond System 235 in Dublin, Ireland " Journal of Water Sustainability 4 (1):13-26. 236 Tomasko, David, Mike Britt, and M. Carnevale. 2016. "The ability of barley straw, cypress leaves and L-lysine to 237 inhibit cyanobacteria in Lake Hancock, a hypereutrophic lake in Florida." Florida Scientist 79:147-157. 238 Xiao, X., H. Huang, Z. Ge, T. B. Rounge, J. Shi, X. Xu, R. Li, and Y. Chen. 2014. "A pair of chiral flavonolignans 239 as novel anti-cyanobacterial allelochemicals derived from barley straw (Hordeum vulgare): characterization 240 and comparison of their anti-cyanobacterial activities." Environ Microbiol 16 (5):1238-51. doi: 241 10.1111/1462-2920.12226. 242 Xiao, Xi, Ying-xu Chen, Xin-qiang Liang, Li-ping Lou, and Xian-jin Tang. 2010. "Effects of Tibetan hulless barley 243 on bloom-forming cyanobacterium (Microcystis aeruginosa) measured by different physiological and 244 morphologic parameters." Chemosphere 81 (9):1118-1123. doi: 245 https://doi.org/10.1016/j.chemosphere.2010.09.001.

207 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

246 BACTERIAL BIOMANIPULATION

247 In-lake Intervention Strategy Emerging Supporting Field Data

248 Indigenous bacteria as well as viruses and fungi have been suggested as agents that can remove 249 cyanobacterial cells from the water column via a broad range of mechanisms (Sigee et al. 1999). 250 Some bacteria may settle cyanobacteria out of the water column by aggregation/bio-flocculation; 251 other bacteria and viruses may lyse (break open) cyanobacteria cells; still other bacteria may 252 degrade microcystins and perhaps other cyanotoxins. A relatively new hybrid application 253 involves using microporous bubbling aeration techniques to de-stratify the lake and reoxygenate 254 deep bottom waters, then seeding the bottom sediments with bacteria or enzyme mixtures to 255 oxidize settled cyanobacteria and reduce the availability of nutrients that would support 256 cyanobacteria re-growth. The hybrid treatment appears to be most effective when de- 257 stratification and bottom organic matter oxidation is followed by the addition of micronutrients 258 that favor the growth of non-cyanobacteria. There is concern, however, that the introduction of 259 non-native or engineered bacteria may have unforeseen and irreversible consequences, e.g., 260 altering bacterial communities and processes that drive ecosystem dynamics.

261 Several naturally occurring bacteria are included as potential biological control agents. These 262 include members of the Bacteroides-Cytophaga-Flavobacterium complex and specifically 263 Bacillus spp., Flexibacter spp., Cytophaga, and Myxobacteria (Gumbo, Ross, and Cloete 2008). 264 For these bacteria to be used for biocontrol, they must have densities approximating 106/mL and 265 complement high cyanobacteria abundances, ensuring close contact between the two 266 populations. In the laboratory, Nakamura et al. (2003) inoculated a “floating carrier” of 267 biodegradable starch-based plastic with Bacillus cereus N-14. The addition yielded a 99% 268 decline in planktonic cyanobacteria in 4 days; without the carrier, the decline was only 7.5%.

269 As initially stated, attaining high population densities of the desirable bacteria in small volumes 270 should be relatively inexpensive to accomplish, since the methods to culture bacteria are well 271 known and can be readily applied. However, scaling up to volumes of bacteria needed for whole 272 lake application would be expensive. (Wang et al. 2020) described the use of bacteria as a 273 control because of their ‘potential effectiveness, species specificity, and eco-friendly 274 characteristics.’ While use of bacteria to control blooms may eventually be a cost effective as 275 well as safe treatments, timing for posting the treatment for general use in a lake for recreation or 276 drinking water is unknown. Since EPS (exocellular polysaccharides) are produced by bacteria, a 277 non-contact period for recreational waters might be considered to avoid potential allergic 278 reactions to these by-products. Additionally, cyanotoxin analyses for drinking and recreational 279 waters should occur, as toxins can be released when cells are lysed or settle out of the water 280 column and break down in the sediments. This might be mitigated through the addition of a 281 second microcystin-degrading bacterium or assemblage.

282

208 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

EFFECTIVENESS NATURE OF HCB • Water body types: pond, lake/reservoir • Surface bloom of cyanobacteria, e.g., • Surface area: small Microcystis aeruginosa is a good candidate • Depth: deep • Toxic and non-toxic HCBs • Trophic status: eutrophic • Intervention strategy • Any mixing regime • Alkaline systems • Water body uses: recreation, drinking water • Confined to bloom area or isolated coves • No carry over from bloom to bloom as with metals

283 The use of bacteria for cyanobacteria removal requires a surface cyanobacteria bloom, a high 284 density of added bacteria, and interventions to ensure high bacteria-cyanobacteria contact, e.g., a 285 biofloc or floatation carriers. A section of a lake can be isolated, e.g., a cove on the windward 286 side of the lake or with vertical weir curtains that can be ‘dropped’ in a lake.

ADVANTAGES LIMITATIONS • Unlikely carry-over after bloom • Very limited field use to date dissipation as the added bacteria can then • Needs laboratory to culture the large shift to a different energy source volumes of bacteria, a boat for delivery, and • Low potential for adverse impacts if floating inoculated substrates indigenous bacteria are used • Limited toxicity information for cultured bacteria • Solely microcystin degradation to date • Surface water criteria concerns for toxin release as cells lyse • Permitting requirements unknown • Potential long-term irreversible ecosystem impacts if non-indigenous bacteria are used 287 COST ANALYSIS

288 No cost projections are readily available, but initial costs would be high for culturing equipment, 289 i.e. large volume vats, autoclaves, incubators, glassware, media, and expendables. There would 290 be costs for preparing starch-based ‘carriers’ and methods and space for inoculating these 291 substrates. The use/reuse of vertical weir curtains (these separate water bodies) further increases 292 costs. Staffing and time demands would be substantial.

293 Table 1: Bacterial biomanipulation cost analysis per growing season.

ITEM RELATIVE COST PER GROWING SEASON Material $$$ Personal Protective Equipment $$

209 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Equipment $$$ Machinery $$ Tools $$

Labor $$$ O&M Costs $$ OVERALL $$$

294 REGULATORY AND POLICY CONSIDERATIONS

295 Permitting requirements are unknown but adding live bacteria to natural waters needs evaluation.

296 REFERENCES

297 Gumbo, Jabulani, Gina Ross, and Thomas Cloete. 2008. "Biological control of Microcystis dominated harmful algal 298 blooms." African Journal of Biotechnology 7. 299 Nakamura, N., K. Nakano, N. Sugiura, and M. Matsumura. 2003. "A novel control process of cyanobacterial bloom 300 using cyanobacteriolytic bacteria immobilized in floating biodegradable plastic carriers." Environ Technol 301 24 (12):1569-76. doi: 10.1080/09593330309385703. 302 Sigee, D., R. Glenn, M. Andrews, Edward Bellinger, R. Butler, H. Epton, and R. Hendry. 1999. "Biological control 303 of cyanobacteria: Principles and possibilities." Hydrobiologia 395-396:161-172. doi: 304 10.1023/A:1017097502124. 305 Wang, Meng, Shibao Chen, Wenguang Zhou, Wenqiao Yuan, and Duo Wang. 2020. "Algal cell lysis by bacteria: A 306 review and comparison to conventional methods." Algal Research 46:101794. doi: 307 https://doi.org/10.1016/j.algal.2020.101794.

308

210 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

309 CHLORINE COMPOUNDS

310 In-lake Intervention Strategy Limited Supporting Field Data

311 Chlorine is a common disinfectant used as a controlling substance for cyanobacteria in finished 312 drinking water. However, its efficacy in open water systems remains relatively unknown. The 313 information below documents the use of chlorination in drinking water plants, revealing its 314 reactivity and thereby, possible future use in open waters.

315 Chlorine compounds in solid, liquid, or gaseous forms are added to decontaminate a water 316 source. Chlorination is primarily used in the disinfection stage of drinking water treatment but 317 may also be applied directly to the raw intake. Chlorine compounds that have been substantially 318 investigated with regard to effective removal of cyanotoxins include free chlorine, chlorine 319 dioxide, and chloramine. The chemical structure of the compounds influences their reactivity 320 with oxidants such as chlorine and ozone, as well as affecting the by-product compounds 321 produced during disinfection (He et al. 2016). Different cyanobacteria species have different 322 sensitivity toward chlorine oxidation (He et al. 2016). Also, the cell damage resulting from 323 chlorination raises significant concern due to the release of cyanotoxins, taste and odor 324 compounds, and intracellular organic matter, leading to the production of toxic disinfection 325 byproducts (He et al. 2016). For drinking water systems in particular, special care must be taken 326 to distinguish between the removal or destruction of cyanobacterial cells and the destruction of 327 cyanotoxins.

328 The destruction of cyanotoxins by free chlorine is variable and depends on the particular toxin 329 (He et al. 2016, Rodríguez et al. 2007). Free chlorine can effectively destroy microcystins and 330 cylindrospermopsin under optimized treatment conditions (Acero, Rodriguez, and Meriluoto 331 2005, Rodríguez et al. 2007) but can be less effective in destroying other cyanotoxins (He et al. 332 2016). The pH of the water during treatment plays an especially important role and the 333 effectiveness of chlorine for destroying microcystins. This effectiveness has been shown to 334 decrease with decreasing pH (Acero, Rodriguez, and Meriluoto 2005, He et al. 2016, Westrick et 335 al. 2010). However, some studies have found that even relatively low doses of chlorine (<1 mg 336 L-1) are sufficient for degradation of cylindrospermopsin when the carbon content is low 337 (Senogles et al. 2000). But if organic matter other than cylindrospermopsin is present, the 338 effectiveness of chlorine is reduced as other organic matter consumes chlorine (Senogles et al. 339 2000).

340 Chlorine dioxide has also been investigated for the removal of cyanotoxins, however, 341 information is limited, likely due to the fact that chlorine dioxide is much less effective in the 342 removal of cyanotoxins compared to other oxidants (He et al. 2016). Chlorine dioxide is not 343 effective for the destruction of microcystins or cylindrospermopsin (Westrick et al. 2010, 344 AWWA 2001) and there is inadequate information demonstrating the effectiveness of chlorine 345 dioxide for the destruction of other toxins (AWWA 2001). Information on the inactivation of 346 cyanobacteria by chloramine is scarce (He et al. 2016). Chloramine is the least effective oxidant 347 for inactivating certain cyanobacteria species and is not effective for the destruction of 348 microcystin or cylindrospermopsin (AWWA 2001, Westrick et al. 2010).

211 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

EFFECTIVENESS NATURE OF HCB • Water body types: lake/reservoir, river • Can treat both singular and repeating intake to a drinking water facility blooms • Any depth or surface area, but typically • Most effective for microcystins and most effective in large drinking water cylindrospermopsin, less effective for other reservoir intakes cyanotoxins • Any trophic state, but typically most • Toxic HCBs effective in oligotrophic systems • Intervention strategy • Any water body uses

349 Of the conventional processes used for drinking water treatment, chlorine can be most easily 350 modified to enhance the removal of either toxic cyanobacterial cells and/or cyanotoxins (He et 351 al. 2016). However, this disinfection generally requires a chlorine exposure (“CT”) value higher 352 than typically used for other treatment objectives (He et al. 2016). Also, one single disinfectant 353 will not be effective for all cyanotoxins. Therefore, multiple disinfectants or treatment processes 354 may be needed to ensure effective removal of a variety of cyanotoxins and the destruction of 355 cyanopeptides (other toxic compounds from the cyanobacteria) is a developing research area.

ADVANTAGES LIMITATIONS • Thorough documentation for use as • Open water studies needed treatment in drinking water facilities for • May need infrastructure depending on HCB and non-HCB uses whether you are treating the source water or • Relatively low risk for adverse impact at the raw water intake of a drinking water small doeses treatment facility • Scalable • Has been shown to be ineffective in treating certain cyanobacteria species or in non- optimized conditions • Can produce toxic disinfection byproducts that may impact drinking water treatment, recreational use, and wildlife

356 Elemental chlorine is constantly combining with surrounding chemicals, creating secondary 357 compounds. The consequence of excess chlorine is largely influenced by the exposure period or 358 contact time. When placed into a natural environment or ecosystem, it is not necessarily the 359 chlorine that can have harmful impacts but rather secondary compounds that can cause serious 360 damage to aquatic life as well as contamination of edible fish (Moore 2017). Because chlorine is 361 so reactive, it can also react with oxygen in air and soil nitrogen, ultimately affecting terrestrial 362 organisms as well (Moore 2017).

363 COST ANALYSIS

364 Watershed management plays a major role in controlling the cost of chlorinating drinking water, 365 as treating drinking water from surface water is typically more expensive than treating 366 groundwater which has been filtered naturally (Oram 2019). Drinking water facility treatment

212 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

367 costs will vary based on water quality, as CASE STUDY EXAMPLE 368 chlorination at cost-effective doses can be 369 more or less effective depending on a number Reservoir, Toledo, OH: In early August 370 of water quality indicators (Acero, Rodriguez, 2014, the City of Toledo, Ohio reported 2.5 371 and Meriluoto 2005, He et al. 2016, Rodríguez mg/L microcystin equivalents in the finished 372 et al. 2007). Chlorination as a strategy for water (USEPA 2015). The level exceeded 373 controlling HCBs in open waters, however, has the Ohio Environmental Protection Agency 374 not been evaluated and hence, costs of field use (Ohio EPA) threshold, and the state 375 cannot be exactly estimated. recommended the city post a “do not drink” advisory. 376 Table 1: Chlorine compounds (used in a 377 drinking water treatment facility) cost analysis Within 55 h, the city had optimized their 378 per growing season. treatment through increased dosing with ITEM RELATIVE COST PER permanganate, powdered activated carbon, GROWING SEASON alum, and chlorine. Eleven days later, the microcystin concentration increased to Material $$ above 50 mg/L microcystin-LR equivalents in the raw (untreated) influent water. Personal Protective $ However, with this optimized system, the Equipment utility was able to maintain effluent concentrations below the 1.0 mg/L Equipment $$ microcystin-LR equivalents threshold. For the 2015 season, the utility has increased Labor $ their powder activated carbon (PAC) feed capacity and the city was investigating the O&M Costs $$ addition of ozone to their treatment train. (He et al. 2016) OVERALL $$

379

380 REGULATORY AND POLICY CONSIDERATIONS

381 While chlorine is well established as a disinfectant in drinking water treatment processes, 382 policies and regulations may differ by state, and locality. Regardless, application permits are 383 required in most places, and applications are often limited to approved products at recommended 384 doses. Registered/licensed engineering professionals are often required to apply chlorine in 385 drinking water treatment, and following future field pilot studies, should be employed similarly 386 for raw water body treatment. Frequency of treatments may be restricted in certain water bodies 387 by state policy. Water body use restrictions based on chlorine dosages are presented on the 388 products’ safety datasheets.

389

390

213 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

391 REFERENCES

392 Acero, J. L., E. Rodriguez, and J. Meriluoto. 2005. "Kinetics of reactions between chlorine and the cyanobacterial 393 toxins microcystins." Water Res 39 (8):1628-38. doi: 10.1016/j.watres.2005.01.022. 394 AWWA. 2001. White Paper on Algal Toxin Treatment American Water Works Association, Ohio. 395 He, X., Y. L. Liu, A. Conklin, J. Westrick, L. K. Weavers, D. D. Dionysiou, J. J. Lenhart, P. J. Mouser, D. Szlag, 396 and H. W. Walker. 2016. "Toxic cyanobacteria and drinking water: Impacts, detection, and treatment." 397 Harmful Algae 54:174-193. doi: 10.1016/j.hal.2016.01.001. 398 Moore, Sarah. 2017. "Does Chlorine Gas have a Negative Effect on the Environment?" Seattle Pi, 399 Education/College and Higher Education. 400 Oram, Brian. 2019. "Water Supply System-Chlorination." Water Research Center. https://water- 401 research.net/index.php/water-treatment/tools/chlorination-of-water. 402 Rodríguez, E., G. D. Onstad, T. P. Kull, J. S. Metcalf, J. L. Acero, and U. von Gunten. 2007. "Oxidative elimination 403 of cyanotoxins: comparison of ozone, chlorine, chlorine dioxide and permanganate." Water Res 41 404 (15):3381-93. doi: 10.1016/j.watres.2007.03.033. 405 Senogles, P., G. Shaw, M. Smith, R. Norris, R. Chiswell, J. Mueller, R. Sadler, and G. Eaglesham. 2000. 406 "Degradation of the cyanobacterial toxin cylindrospermopsin, from Cylindrospermopsis raciborskii, by 407 chlorination." Toxicon 38 (9):1203-13. doi: 10.1016/s0041-0101(99)00210-x. 408 USEPA. 2015. Recommendations for Public Water Systems to Manage Cyanotoxins in Drinking Water EPA 815- 409 R-15-010. edited by Chesapeake Bay Program US. S. Environmental Protection Agency: US. S. 410 Environmental Protection Agency, Chesapeake Bay Program. 411 Westrick, J. A., D. C. Szlag, B. J. Southwell, and J. Sinclair. 2010. "A review of cyanobacteria and cyanotoxins 412 removal/inactivation in drinking water treatment." Anal Bioanal Chem 397 (5):1705-14. doi: 413 10.1007/s00216-010-3709-5.

414

415 .

214 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

416 CLAY AND SURFACTANT FLOCCULATION

417 In-lake Intervention Strategy Substantial Supporting Field Data

418 Flocculation is the use of added compounds to bind, inactivate, and/or sink harmful algae or 419 cyanobacteria. After the strategy was implemented successfully in marine systems (reviewed in 420 (Sengco and Anderson 2004), investigation began for use of this intervention to control 421 freshwater cyanobacteria blooms (Pan et al. 2006, Zou et al. 2006). Research teams tested an 422 acidified mixture of local sediments combined with surfactants like chitosan (crustacean shell 423 derivative) or polyaluminum chloride (PAC). These proved effective in the flocculation and 424 settling of HCB blooms and some of their associated toxins in a variety of water bodies, from 425 ponds and lakes to brackish estuaries. A mixture of suspended sediment/PAC/chitosan to reach 426 100 mg soil/10 mg PAC/5 mg chitosan in a lake (Pan, Chen, and Anderson 2011) followed by 427 capping (covering) with local sands can remove the HCB and support growth of submersed 428 grasses, which are effective nutrient and sediment traps and provide habitat for many juvenile 429 fish (Pan et al. 2019, Pan et al. 2011).

EFFECTIVENESS NATURE OF HCB • Any water body type • All HCB types • Any surface area or depth • Singular or repeating HCBs • Any trophic state • Toxic and non-toxic HCBs; can remove • Water body uses: recreation, drinking toxins as well as cells water source, aquaculture • Intervention strategy • If no capping is done, best if used in a system with high flushing rates

430 The technique is effective for most ponds, lakes, reservoirs, and saline environments. The 431 surfactant chitosan can be dissolved thoroughly in 0.1 N HCl or dilute vinegar (i.e. acetic acid). 432 Because the flocculated material settles, capping can prevent resuspension and bloom return. If 433 the capping material is mixed with seeds of submersed grasses, revegetation of HCB areas can 434 occur (Pan et al. 2011). If capping is not employed in deep, stratified systems, decomposition of 435 settled material can promote oxygen reduction and associated problems with hypoxia, anoxia, 436 and loss of habitat and induce high nutrient fluxes from the sediments.

ADVANTAGES LIMITATIONS • Effective for most HCBs • May require permit for dispersal • Removes cells and toxins • Requires large volumes of acidic surfactants • Used in many areas and sediments, high volume pumps • Spray dispersal easy • Scalable but costly with increasing HCB area • May impact bottom oxygen levels and benthic fauna and increase nutrient fluxes • Repeated additions may be required

215 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

437

438 Figure 1: Spraying of local soils and chitosan in China.

439 Figure source: Yantai Dajing Eco-environmental Tech Ltd. Used with permission.

440 COST ANALYSIS 441 In one study (Pan et al. 2019), costs ranged CASE STUDY EXAMPLES 442 from $148-$245/acre with two different 443 surfactants and sediments; with capping, the Xuanwu Lake, China: Peak abundances of 444 cost increases to $3648-$8197/acre. Costs for Microcystis aeruginosa exceeded 2.7×107 445 sediment, surfactants, pumps, and hosing can be cells/mL in the summer of 2005. Through 446 high and are proportional to treatment area. A intermittent spraying of modified clays (3- 447 boat may be required if the HCB cannot be 5 tons/km2/d or 30-50 tons/km2 over 10 448 treated from the shore. days), M. aeruginosa was reduced to 6×103 cells/mL and dissolved microcystin 449 Table 1: Flocculation cost analysis per growing reduced to <0.01 μg/L from 0.03–0.62 450 season. μg/L. Removal of flagellated algal blooms required rigorous sediment preparations ITEM RELATIVE COST and costly infrastructure for dispersal (Yu PER GROWING et al. 2017). SEASON Material $$ South Korea: Clays and electrolysis of Personal Protective $ local seawater has been used to remove Equipment toxic dinoflagellates in aquaculture areas. Equipment $$-$$$ Park et al. (2013). Machin $$ Tools $ Labor $$ O&M Costs $ OVERALL $$-$$$

216 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

451 REGULATORY AND POLICY CASE STUDY EXAMPLES 452 CONSIDERATIONS Lake Tai and Cetian Reservoir, China: 453 Dispersing sediment may require a permit. If Chitosan flakes were dissolved in 0.5% 454 flocculation is not followed by capping, acetic acid (vinegar) and stirred until all 455 estimates of bottom impact should be the chitosan was dissolved; the solution 456 considered; i.e. smothering of bottom plants and was diluted with pond water to obtain a 457 animals, development of hypoxia/anoxia and final concentration of 1 g/L before use. 458 associated loss of habitat for fish, as well as Based on lake acreage, the required 459 enhanced nutrient fluxes from bottom sediments volume of chitosan solution was mixed 460 that could exacerbate additional blooms. with the soil suspension (diluted using pond water) to make up a final 461 REFERENCES concentration of 100 mg soil/L and 3 mg chitosan/L in the pond after spraying. For 462 Pan, G, X. Miao, L. Bi, H. Zhang, L. Wang, L. Wang, Z. 463 Wang, J. Chen, J. Ali, M. Pan, J. Zhang, B. Yue, the Cetian Reservoir pond experiment, 464 and T. Lyu. 2019. "Modified Local Soil (MLS) chitosan-PAC modified local sediment 465 Technology for Harmful Algal Bloom Control, (MLS) was prepared by adding dissolved 466 Sediment Remediation, and Ecological PAC to chitosan-modified local soils to 467 Restoration." Water 11. doi: achieve a final concentration of 100 mg 468 https://doi.org/10.3390/w11061123. 469 Pan, G., J. Chen, and D. M. Anderson. 2011. "Modified soil/L, 10 mg PAC/L, and 5 mg chitosan/L 470 local sands for the mitigation of harmful algal in the pond. In the latter, nutrient 471 blooms." Harmful Algae 10 (4):381-387. doi: concentrations and chemical oxygen 472 10.1016/j.hal.2011.01.003. demand (COD) dramatically declined (Pan 473 Pan, G., H. Zou, H. Chen, and X. Yuan. 2006. "Removal et al. 2019). 474 of harmful cyanobacterial blooms in Taihu Lake 475 using local soils. III. Factors affecting the 476 removal efficiency and an in situ field Tanxi Bay, Lake Tai, China: In 2012, 477 experiment using chitosan-modified local soils." approximately 16 kg of chitosan-MLS was 478 Environ Pollut 141 (2):206-12. doi: sprayed into a 400 m2, 1.5 m depth pond 479 10.1016/j.envpol.2005.08.047. with a Secchi depth <5 cm. After 480 Pan, Gang, Bo Yang, Dan Wang, Hao Chen, Bing-hui treatment, the blooms were removed from 481 Tian, Mu-lan Zhang, Xian-zheng Yuan, and Juan 482 Chen. 2011. "In-lake algal bloom removal and the pond within 2 h and Secchi depth 483 submerged vegetation restoration using modified (water clarity) increased to 1.5 m on the 484 local soils." Ecological Engineering 37:302-308. second day. Chl-a concentration in the 485 doi: 10.1016/j.ecoleng.2010.11.019. treated pond decreased from 85 to 13 µg/L 486 Park, Tae Gyu, Weol Ae Lim, Young Tae Park, Chang and remained below this level for 20 days 487 Kyu Lee, and Hae Jin Jeong. 2013. "Economic 488 impact, management and mitigation of red tides after the treatment; Chl-a in the control 489 in Korea." Harmful Algae 30:S131-S143. doi: pond continually increased, reaching a 490 https://doi.org/10.1016/j.hal.2013.10.012. concentration of 350 µg/L on day 20. 491 Sengco, Mario, and Donald Anderson. 2004. "Controlling Turbidity was reduced from 95 to 5.3 NTU 492 Harmful Algal Blooms Through Clay in the treatment pond, while it was 493 Flocculation1." The Journal of eukaryotic 494 microbiology 51:169-72. doi: 10.1111/j.1550- maintained above 100 NTU in the control 495 7408.2004.tb00541.x. pond during the same period. COD and 496 Yu, Xiaoqi, Guanjing Cai, Hui Wang, Zhong Hu, Wei nutrient concentrations declined as well 497 Zheng, Xueqian Lei, Xiaoying Zhu, Yao Chen, (Pan et al. 2019). 498 Qiuliang Chen, Hongyan Din, Hong Xu, Yun 499 Tian, Lijun Fu, and Tianling Zheng. 2017. "Fast- 217 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

500 growing algicidal Streptomyces sp. U3 and its potential in harmful algal bloom controls." Journal of 501 Hazardous Materials 341. doi: 10.1016/j.jhazmat.2017.06.046. 502 Zou, Hua, Gang Pan, Hao Chen, and Xianzheng Yuan. 2006. "Removal of Cyanobacterial Blooms in Taihu Lake 503 Using Local Soils. II. Effective Removal of Microcystis aeruginosa Using Local Soils and Sediments 504 Modified by Chitosan." Environmental pollution (Barking, Essex : 1987) 141:201-5. doi: 505 10.1016/j.envpol.2005.08.042.

506

507 .

218 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

508 COPPER ALGAECIDES

509 In-lake Intervention and Prevention Strategy Substantial Supporting Field Data

510 Copper algaecides have been used to treat problematic algae and cyanobacteria for more than a 511 century due to their effectiveness (Moore and Kellerman 1905). As such, copper algaecides have 512 been extensively evaluated, and numerous peer-reviewed publications have increased our 513 understanding of copper algaecide efficacy, copper fate, and potential non-target species impacts 514 (Calomeni, Rodgers, and Kinley-Baird 2014, Fitzgerald and Faust 1963, Gibson 1972, Iwinski et 515 al. 2017, Kinley et al. 2017, Murray-Gulde et al. 2002). Copper algaecides are chemical 516 treatments that impact an algal or cyanobacterial cell’s ability to respire and photosynthesize. and 517 at some concentrations they can impact cell integrity causing them to become non-viable and 518 lyse (Calomeni, Rodgers, and Kinley-Baird 2014, Gibson 1972).

519 There are a variety of forms of copper algaecides and algal/cyanobacterial responses to these 520 algaecides range as a function of innate algal and cyanobacterial sensitivities (Calomeni, 521 Rodgers, and Kinley-Baird 2014, Iwinski et al. 2017), abundances (Calomeni et al. 2018, Kinley 522 et al. 2017), exposure durations (Calomeni et al. 2018), site characteristics (e.g., water hardness, 523 alkalinity, conductivity, pH) and the copper-based algaecide applied (Fitzgerald and Faust 1963, 524 Murray-Gulde et al. 2002). Different copper algaecides include copper sulfate, acidified copper 525 products, chelated copper algaecides (e.g. copper ethanolamine, copper citrate, and copper 526 gluconate) and products with a variety of additives. Copper algaecides have different trade 527 names and are registered with the USEPA for treatment of harmful algae and cyanobacteria. The 528 product’s label specifies how the compounds may be applied in lakes, reservoirs, ponds, 529 irrigation canals, and other water bodies. To be effective, the algaecide must be applied so that 530 the active ingredient contacts the problematic alga or cyanobacterium. Following an effective 531 algaecide application, cell/population responses can be measured in as little as 1 day after 532 treatment (Bishop and Rodgers 2011, Isaacs et al. 2013).

533 Copper algaecides are often applied when harmful algae and cyanobacteria achieve high 534 densities, producing toxins, and taste and odor compounds that pose risks or interfere with the 535 uses of water resources. The timing of algaecide treatments is often important to ensure 536 treatment success and may limit potential adverse impacts of the algae/cyanobacteria from the 537 algaecide treatment. A detailed management plan that includes explicit triggers for treatments 538 with respect to a measured algal/cyanobacterial cell density, cyanotoxin concentration, or taste 539 and odor compound concentration (Calomeni et al. 2017) is useful for ensuring well timed 540 treatments for sites that experience recurring HCB issues. There are, however, concerns for long- 541 term impacts of copper application associated with possible release of copper under anoxic 542 conditions or at low pH. In the past, treatments were often applied by uncertified applicators 543 using copper concentrations well above current guidelines with shorter periods between 544 treatments. In a recent UNESCO report (Burford et al. 2019), the following guidance is stated for 545 the most commonly used compound, “Historically, copper sulfate was a popular method for 546 controlling cyanobacteria in reservoirs and lakes. However, as knowledge of the toxicity effects 547 of copper on food webs increases, and concern grows about its persistence in sediment, many 548 authorities globally are discouraging its use.”

219 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

EFFECTIVENESS NATURE OF HCB • Water body types: lake/reservoir, river, • Single or repeating HCB bay/estuary • Algal/cyanobacterial sensitivities to copper • Any depth algaecides range but cyanobacteria are often • Surface area: Algaecide labels may specify more sensitive to copper algaecides than applicable area (e.g., maximum of half of green algae the surface area of the water body can be • Intervention or prevention strategy treated at one time) • Any trophic state • Any mixing regime • Water body uses: algaecide labels will specify applicable uses 549

ADVANTAGES LIMITATIONS • More than a century of use and effectiveness • NPDES (National Pollutant Discharge in the United States Elimination System) permits are required • Copper is a micronutrient for treatment in waters of the United States • Copper is naturally occurring in water and • Certified applicators should administer sediment treatment to water bodies • Copper has a lithic biogeochemical cycle • Care is required when treating and will bind with anions in aerobic algae/cyanobacteria in soft waters due to sediment forming copper minerals the sensitivities of non-target species; • Scalable copper is toxic to some fish and many • Copper algaecides can be used to target invertebrates. specific problematic algal/cyanobacterial • There may be long-term ecosystem effects species from release of copper from anoxic bottom sediments or low pH waters

550 Copper algaecides have been applied in water bodies across the United States when problematic 551 algae and cyanobacteria interfere with critical water resource uses and have allowed for the 552 designated uses to be restored. Sites where copper algaecides have been effective range widely in 553 terms of designated water resource uses, problematic alga or cyanobacterium, size (small ponds 554 to thousands of hectare reservoirs), and trophic status. Copper algaecide applications can be 555 scaled to the appropriate size for the water body.

556

220 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

557 COST ANALYSIS 558 The cost of a treatment is a function of the area CASE STUDY EXAMPLES 559 treated, labor, product used and severity of the 560 problematic algal or cyanobacterial issue. One Hartwell Lake, Anderson, South Carolina, 561 previous study in New York had a $933/acre United States: A chelated copper algaecide 562 treatment cost (2020 $US, Appendix 1 and peroxide compound were used to treat 563 [hyperlink appendix]). an assemblage of problematic algae and cyanobacteria and the taste and odor 564 Table 1: Copper algaecides cost analysis per compounds they produced. The taste and 565 growing season. odor compounds resulted in customer complaints associated with the drinking ITEM RELATIVE COST water sourced from Hartwell Lake. PER GROWING SEASON An adaptive water resource management Material $$ approach was used to develop an effective Personal Protective $$ treatment plan for the taste and odor Equipment producing algae and cyanobacteria at the Equipment $$ site. The approach included identification of Machinery $$ the source of taste and odor compounds, and small-scale laboratory studies to determine Tools $$ which algaecide should be used to treat the Labor $$ problematic species. A small-scale pilot OVERALL $$ treatment was applied initially. Three full scale treatments were then applied during 566 REGULATORY AND POLICY 567 the growth season of the problematic CONSIDERATIONS species.

568 Copper algaecides require NPDES permits and The adaptive water resource management 569 are also regulated under the Federal approach along with the chelated copper 570 Insecticide, Fungicide and Rodenticide Act algaecide and peroxide treatments 571 (FIFRA). There may be additional state eliminated customer complaints. This 572 specific restrictions. approach also resulted in a 50% cost savings relative to the previous year when powder 573 REFERENCES activated carbon was used in-plant to 574 Bishop, W. M., and J. H. Rodgers. 2011. "Responses of manage taste and odor in the potable water. 575 Lyngbya magnifica Gardner to an algaecide 576 exposure in the laboratory and field." More information on this case study can be 577 Ecotoxicol Environ Saf 74 (7):1832-8. doi: found in Huddleston et al. (2016). 578 10.1016/j.ecoenv.2011.06.007. 579 Burford, M.A., C.J. Gobler, D.P. Hamilton, P.M. 580 Visser, M. Lurling, and G.A. Codd. 2019. Solutions for managing cyanobacterial blooms: a scientific 581 summary for policy makers. edited by UNESCO. Paris: IOC. 582 Calomeni, Alyssa J, Tyler D Geer, Kyla J Iwinksi, John H Rodgers, Jr., John D Madsen, and Ryan M Wersal. 2017. 583 "Monitoring for National Pollutant Discharge Elimination System Permit Requirements: Algaecides." 584 Journal of Integrated Pest Management 8 (1). doi: 10.1093/jipm/pmx025.

221 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

585 Calomeni, Alyssa J., Ciera M. Kinley, Tyler D. Geer, Maas Hendrikse, and John H. Rodgers. 2018. " Lyngbya 586 wollei responses to copper algaecide exposures predicted using a concentration – exposure time ( CET ) 587 model : Influence of initial biomass." J. Aquat. Plant Manage. 56:73-83. 588 Calomeni, Alyssa, John Rodgers, and Ciera Kinley-Baird. 2014. "Responses of Planktothrix agardhii and 589 Pseudokirchneriella subcapitata to Copper Sulfate (CuSO4 · 5H2O) and a Chelated Copper Compound 590 (Cutrine®-Ultra)." Water Air and Soil Pollution 225:1-15. doi: 10.1007/s11270-014-2231-3. 591 Fitzgerald, G. P., and S. L. Faust. 1963. "Factors affecting the algicidal and algistatic properties of copper." Applied 592 microbiology 11 (4):345-351. 593 Gibson, C.E. . 1972. " The algicidal effects of copper on a green and a bluegreen alga and some ecological 594 implications." J. Appl. Ecol. 9:513-518. 595 Huddleston, M. H., John H. Jr. Rodgers, Kalya Wardlaw, Tyler D. Geer, Alyssa J. Calomeni, Scott Willett, Jennifer 596 J Barrington, David W. Melton, John P. Chastain, Martín Bowen, and Mike Spacil. 2016. "Adaptive Water 597 Resource Management for Taste and Odor Control for the Anderson Regional Joint Water System." 598 Isaacs, David A., Russell G. Brown, William A. Ratajczyk, Nathan W. Long, John H. Rodgers Jr., and James C. 599 Schmidt. 2013. "Solve Taste-and-Odor Problems with Customized Treatment." Opflow 39 (7):26-29. doi: 600 10.5991/opf.2013.39.0039. 601 Iwinski, K. J., J. H. Rodgers, Jr., C. M. Kinley, M. Hendrikse, A. J. Calomeni, A. D. McQueen, T. D. Geer, J. Liang, 602 V. Friesen, and M. Haakensen. 2017. "Influence of CuSO(4) and chelated copper algaecide exposures on 603 biodegradation of microcystin-LR." Chemosphere 174:538-544. doi: 10.1016/j.chemosphere.2017.01.079. 604 Kinley, C. M., K. J. Iwinski, M. Hendrikse, T. D. Geer, and J. H. Rodgers, Jr. 2017. "Cell density dependence of 605 Microcystis aeruginosa responses to copper algaecide concentrations: Implications for microcystin-LR 606 release." Ecotoxicol Environ Saf 145:591-596. doi: 10.1016/j.ecoenv.2017.08.010. 607 Moore, G. T., and K. F. Kellerman. 1905. Copper as an algicide and disinfectant in water supplies. U. S. 608 Government Printing Office. 609 Murray-Gulde, C. L., J. E. Heatley, A. L. Schwartzman, and Jr J. H. Rodgers. 2002. "Algicidal Effectiveness of 610 Clearigate, Cutrine-Plus, and Copper Sulfate and Margins of Safety Associated with Their Use." Archives 611 of Environmental Contamination and Toxicology 43 (1):19-27. doi: 10.1007/s00244-002-1135-1.

612

222 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

613 DREDGING

614 In-lake Prevention Strategy Limited Supporting Field Data

615 Dredging is the physical removal of sediment from the bottom of a water body. In the context of 616 HCB control, dredging is performed to reduce the supply of nutrients from the sediment (internal 617 loading) to the water column. There are many different dredging techniques available, but most 618 can be categorized as either hydraulic or mechanical dredging. Hydraulic dredging works by 619 sucking sediment through a tube to a barge or offshore location. Mechanical dredging involves 620 excavating the sediment with backhoes, clamshells, draglines, or equipment. Dredging for HCB 621 control purposes usually targets the upper, nutrient-enriched sediment layer (e.g. 10-100 cm). 622 The depth to be targeted can be determined by testing sediment phosphorus concentrations at 623 varying depths.

EFFECTIVENESS NATURE OF HCB • Water body type: lake/reservoir • Repeating or persistent HCB • Surface area and depth: cost may limit this • Prevention strategy technique to smaller or shallower water bodies • Water bodies with high internal nutrient loading from sediments but controlled external loads

624 Dredging can be a useful technique for water bodies that have experienced historical nutrient 625 over-enrichment such that internal recycling of nutrients from the sediment is sufficient to 626 support blooms (Peterson 1982). It has the highest potential for success in lakes where sediment 627 fluxes are the dominant nutrient loading source and external nutrient loads have been controlled 628 (Bormans, Marsálek, and Jancula 2015). Dredging also has been successful when combined with 629 other control techniques such as sediment phosphorus inactivation (Lürling and Faassen 2012).

ADVANTAGES LIMITATIONS • Reduced internal nutrient loads • Not effective if external loads still high • Increased lake depth • Requires disposal of dredged material • Dredge material can sometimes be • Requires permitting under the Clean Water beneficially reused Act (33 U.S.C. §§1251-1387, sections 401 and 404) • Temporary increases in turbidity • Impacts to bottom-dwelling aquatic life

223 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

630

631 Figure 1: (A) Mechanical dredging on the upper Hudson River. Photo credit: USEPA. (B) 632 Hydraulic dredging equipment on Easter Lake, Iowa. Photo credit: Snyder and Associates. 633 COST ANALYSIS CASE STUDY EXAMPLES 634 Dredging is one of the most expensive HCB 635 Lake Trummen, Sweden: Extensive efforts control techniques (Bormans, Marsálek, and were made to control external nutrient loads 636 Jancula 2015, Hudson 1998, Peterson 1982). 637 to the historically polluted Lake Trummen, The cost can vary greatly based on the area, Sweden. After hydraulic dredging, 638 depth, and nature of the material to be 639 cyanobacterial blooms largely disappeared dredged. Pre-dredging costs typically include and were replaced by a taxonomically-rich 640 bathymetric surveys, permitting, and chemical 641 phytoplankton community and the analysis of the material to be dredged. recreational potential of the lake was greatly 642 Disposal costs are higher if the material is 643 improved (Björk, Pokorný, and Hauser contaminated or if the disposal area is far 2011). 644 from the lake or reservoir. Conversely, 645 disposal costs can be lower if the material can Lake Vajgar, Czech Republic: An 646 be beneficially reused; e.g. applied to pasture automatically controlled precision dredger 647 or crops as a soil amendment. The Illinois was used to remove the top sediment layer in 648 EPA (Hudson 1998) estimated that typical an attempt to reduce recurring HCBs. 649 costs of dredging in 2020 dollars are $8 to Although sediment nutrient fluxes decreased 650 $24 per cubic yard for hydraulic dredging, dramatically, external nutrient loading was 651 and $13 to $48 per cubic yard for mechanical still high and HCBs continued to occur 652 dredging. For other examples, the average (Björk, Pokorný, and Hauser 2011). 653 cost was $63,443/acre (Appendix 1 654 [hyperlink appendix]). Although is it The scientific literature shows that dredging 655 possible to dredge water bodies of various has mixed results as an HCB control 656 size, costs may limit its practical use for HCB technique, depending upon whether external 657 control to relatively small or shallow water loads have also been controlled, and whether 658 bodies. nutrient limitations on algae can be imposed. See Bormans, Marsálek, and Jancula (2015) 659 for a more extensive literature review of dredging as an HCB control technique.

224 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

660 Table 1: Dredging cost analysis per growing season.

ITEM RELATIVE COST PER GROWING SEASON Planning/Permitting $$ Material $ Equipment $$$ Labor $$$ Disposal $$ OVERALL $$$

661 REGULATORY AND POLICY CONSIDERATIONS

662 In the United States, sections 401 and 404 of the Clean Water Act (33 U.S.C. §§1251-1387) 663 require that those persons or businesses that propose dredging within navigable waters obtain a 664 permit from the U.S. Army Corps of Engineers, the state regulatory agency, and (in some cases) 665 the USEPA. Permitting requirements can be streamlined somewhat by joint permit applications 666 to multiple agencies. Typical permit application requirements include the quantity/extent of 667 dredging, disposal location/method, and expected environmental impacts. In some cases, testing 668 of the dredged material will be required, which could affect disposal requirements.

669 Dredging can have potential co-benefits of increased lake volume, enhanced boat navigation, 670 removal of nuisance macrophytes, enhanced fish production, and removal of toxic sediments 671 (Peterson 1982). In fact, most dredging projects are motivated by one or more of these other 672 drivers rather than by HCB control. In many settings, the level of stakeholder support for 673 dredging projects will be tied to these co-benefits

674 REFERENCES

675 Björk, Sven, Jan Pokorný, and Václav Hauser. 2011. "Restoration of Lakes Through Sediment Removal, with Case 676 Studies from Lakes Trummen, Sweden and Vajgar, Czech Republic." In, 101-122. 677 Bormans, Myriam, Blahoslav Marsálek, and Daniel Jancula. 2015. "Controlling internal phosphorus loading in lakes 678 by physical methods to reduce cyanobacterial blooms: a review." Aquatic Ecology 50. doi: 679 10.1007/s10452-015-9564-x. 680 Hudson, Holly. 1998. Dredging. edited by Illinois Environmental Protection Agency. SpringField, IL: Illinois 681 Environmental Protection Agency 682 Lürling, M., and E. J. Faassen. 2012. "Controlling toxic cyanobacteria: effects of dredging and phosphorus-binding 683 clay on cyanobacteria and microcystins." Water Res 46 (5):1447-59. doi: 10.1016/j.watres.2011.11.008. 684 Peterson, Spencer A. 1982. "LAKE RESTORATION BY SEDIMENT REMOVAL1." JAWRA Journal of the 685 American Water Resources Association 18 (3):423-436. doi: 10.1111/j.1752-1688.1982.tb00009.x.

686

687

225 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

688 FLOATING WETLANDS

689 In-lake Prevention Strategy Limited Supporting Data

690 Artificial floating vegetated islands have been employed since the 1970s and 80s for removing 691 nutrients from ponds, lakes, or reservoirs and thus discouraging the algal/cyanobacterial blooms 692 that are favored by high nutrient levels (Hoeger 1988). Several applications have taken place in 693 Asia (Lu, Ku, and Chang 2015, Ning et al. 2014). Islands of various sizes, materials, and designs 694 have been constructed to provide platforms for suspending a variety of emergent plant 695 vegetation. The vegetation is integral to the designs, because the plants take up dissolved 696 nutrients through their roots which are suspended in the aquatic ecosystem.

697 This ‘hydroponics-like’ approach for nutrient capture is conceptually and theoretically sound 698 (Wang and Sample 2013). Plant roots suspended in the water below the islands continually 699 sequester nutrients from the water. Development of microbial communities attached to the roots 700 of the plants further increases the drawdown of dissolved nutrients (Masters 2012). Periodic 701 harvesting of plant material from the island results in a net removal of nutrients from the system.

EFFECTIVENESS NATURE OF HCB • Water body type: lake/reservoir • All HCB types • Surface area: small • Singular or repeating HCB • Depth: shallow • Toxic and non-toxic HCB • Trophic state: eutrophic, hypereutrophic • Targets all algal species • Any mixing regime • Prevention strategy

702 The effectiveness of this approach for nutrient reduction is determined by a number of factors 703 and the field is still in a state of optimizing the approach (Dunqiu et al. 2012). Ultimately their 704 effectiveness depends on the surface area covered by islands relative to the volume of the water 705 body, and the magnitude of internal and external nutrient loading relative to the rate of nutrient 706 removal by the islands. The rate of nutrient capture and removal by these islands is dependent 707 not only on island size, but also on the type of vegetation employed and various environmental 708 factors that affect primary production by the plants (e.g. light, temperature, nutrient 709 concentrations in the water body). These features are difficult to quantify, making it difficult to 710 create a generalized approach that will be universally successful. The Chesapeake Bay Program 711 has convened two expert panels to set nutrient removal efficiencies and concluded that these 712 features were appropriate for storm water ponds and not open waters, where 10-50% areal 713 coverage would result in increasing nutrient removal credit towards Total Maximum Daily Load 714 (TMDL) limits (Schueler, Lane, and Wood 2016).

715 There are a number of anecdotal reports or one-off ‘success stories’ that have claimed 716 effectiveness, but relatively few scientific studies have clearly demonstrated that the approach 717 can result in significant nutrient reduction (Geng et al. 2017, Lu, Ku, and Chang 2015, Vázquez- 718 Burney et al. 2015). There are also a fair number of reports appearing in the non-reviewed lay- 719 person factsheets and reports, as well as abstracts from conference proceedings or other 720 documents and publications that are not peer-reviewed. Growth and nutrient uptake by a number 721 of candidate plant species has been tested on artificial islands (Geng et al. 2017, Yao et al. 2011, 226 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

722 Zhu, Li, and Ketola 2011), demonstrating that nutrients are indeed acquired by the island plants. 723 However, studies demonstrating that such nutrient uptake and removal is a significant fraction of 724 the total nutrient load of the aquatic ecosystem are scarce.

725 The anticipated or supposed effect of floating islands is a reduction in nutrient concentrations, 726 resulting in overall reduction of algal/cyanobacterial growth. However, it is also possible (but 727 largely untested) that shifts in plankton community structure away from harmful or noxious 728 algal/cyanobacterial species may occur due to the activities of the plants or their attendant root 729 microbes. Additionally, reductions or changes in the plankton community as a consequence of 730 reduced light penetration (due to the presence of the floating islands) have been suggested but 731 not quantified.

ADVANTAGES LIMITATIONS • Reduction of nutrient loads by uptake and • High cost required for island design, removal of plant tissue construction, deployment, maintenance, • Reduced light penetration into the water harvesting, and replanting column, reducing primary production • Substantive nutrient reduction in the treated • Reduced wind-driven circulation may water body requires prolonged use reduce deep mixing of the water column, • Rate of nutrient removal must be high reducing nutrient transport relative to internal loads, and greater than • Thermal insulation may reduce summer external loading high water temperatures, constraining • Plant growth is most rapid and luxurious at cyanobacterial growth high (hypereutrophic) nutrient • Plant roots provide increased biotic concentrations (Cao and Zhang 2014) - surface area for microbial growth, Efficacy at “environmentally relevant” enhancing nutrient removal concentrations is not clear • Plant root microbes may increase • Application has been carried out only in predation on the planktonic microbes freshwater environments • Can be harvested • Reduced wind-driven circulation may reduce deep mixing of the water column and lead to greater stratification and increases in nutrients from low oxygen bottom sediments

227 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

732 733 Figure 1. Examples of commercially available floating artificial islands with emergent plants. 734 (A) mature growth on small islands bordering a walkway. (B) an early stage of plant growth

735 COST ANALYSIS CASE STUDY EXAMPLES 736 There are significant costs associated with 737 floating islands, their deployment, and Florida, United States: Floating wetland 738 maintenance. Commercial entities offer islands resulted in a 32% removal of nitrogen 739 design, construction, deployment, and (mostly organic nitrogen) in the outflow from 740 maintenance. Islands require substantial a reservoir receiving wastewater effluent 741 materials and labor for constructing the (Vázquez-Burney et al. 2015). 742 floating islands, mooring them and planting 743 them. Maintenance, harvesting, and Laboratory-scale: A test of nitrogen and 744 replanting islands can be labor intensive phosphorus removal from simulated 745 while removal (which may be necessary agricultural/wastewater runoff (liquid 746 seasonally) and redeployment can be costly. hydroponic fertilizer) was conducted by 747 Harvested plant materials must also be Stewart et al. (2008). Removal of both 748 composted or otherwise removed. Finally, elements was demonstrable, at least at very 749 environmental monitoring should be high dissolved nutrient concentrations. Such 750 conducted (e.g. water clarity, nutrient results are proof-of-concept for artificial 751 concentrations, phytoplankton islands, but there is still very limited 752 characterizations) in order to document that information on how effective the approach 753 the artificial islands are positively affecting will be at much lower, environmentally 754 water quality and reducing nutrient loads relevant nutrient concentrations (Stewart et al. 755 within the water body. 2008).

756

757

758

228 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

759 Table 1: Floating wetlands cost analysis per CASE STUDY EXAMPLES 760 growing season. Stormwater retention ponds, Auckland, New ITEM RELATIVE COST Zealand: Examined phosphorus removal by PER GROWING floating wetlands on water passing through SEASON stormwater retention ponds. The study Material $$$ concluded that the floating wetlands reduced Personal Protective $ phosphorus in the water discharged from the Equipment ponds, but that sedimentation, rather than Equipment $ uptake by plants, was the main process Machinery $ reducing phosphorus in the discharge water. Tools $ Borne (2014). Labor $$$ O&M Costs $$ OVERALL $$$ 761

762 REGULATORY AND POLICY CONSIDERATIONS

763 Permits for deployment of artificial islands may vary widely, depending on 764 ownership/management/jurisdiction of the water body. For example, private lakes may require 765 only the permission from the homeowner’s association, whereas waters under municipal/state or 766 federal jurisdiction may involve permitting from the city, county, state of federal government.

767 Public acceptance of this approach stems largely from public perspective on the islands 768 themselves and that is typically and often decidedly mixed. Some residents clearly accept the 769 islands (if they are well-designed and deployed) as they provide clear evidence that ‘something is 770 being done’ to address an existing problem. However, aesthetics are important. Complaints about 771 artificial islands as ‘eye sores’ are not unusual among neighbors and visitors. More significantly, 772 hindrances to boating, water skiing, and other recreational activities (e.g. fishing, swimming) are 773 potential detractors for the public.

774 REFERENCES

775 Borne, Karine E. 2014. "Floating treatment wetland influences on the fate and removal performance of phosphorus 776 in stormwater retention ponds." Ecological Engineering 69:76-82. doi: 777 https://doi.org/10.1016/j.ecoleng.2014.03.062. 778 Dunqiu, W., B. Shaoyuan, W. Mingyu, X. Qinglin, Z. Yinian, and Z. Hua. 2012. "Effect of artificial aeration, 779 temperature, and structure on nutrient removal in constructed floating islands." Water Environ Res 84 780 (5):405-10. doi: 10.2175/106143012x13347678384684. 781 Geng, Yan, Wenjuan Han, Chenchen Yu, Qinsu Jiang, Jianzhi Wu, Jie Chang, and Ying Ge. 2017. "Effect of plant 782 diversity on phosphorus removal in hydroponic microcosms simulating floating constructed wetlands." 783 Ecological Engineering 107:110-119. doi: https://doi.org/10.1016/j.ecoleng.2017.06.061. 784 Hoeger, Sven. 1988. "Schwimmkampen." Germany's artificial floating islands 43 (4):304-306. 785 Lu, Hsiao-Ling, Chen-Ruei Ku, and Yuan-Hsiou Chang. 2015. "Water quality improvement with artificial floating 786 islands." Ecological Engineering 74:371-375. doi: https://doi.org/10.1016/j.ecoleng.2014.11.013. 787 Masters, Bernie. 2012. "The ability of vegetated floating Islands to improve water quality in natural and constructed 788 wetlands: a review." Water Practice and Technology 7 (1). doi: 10.2166/wpt.2012.022.

229 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

789 Ning, D., Y. Huang, R. Pan, F. Wang, and H. Wang. 2014. "Effect of eco-remediation using planted floating bed 790 system on nutrients and heavy metals in urban river water and sediment: a field study in China." Sci Total 791 Environ 485-486:596-603. doi: 10.1016/j.scitotenv.2014.03.103. 792 Schueler, Tom, Cecilia Lane, and David Wood. 2016. Recommendations of the Expert Panel to Define Removal 793 Rates for Floating Treatment Wetlands in Existing Wet Ponds edited by Chesapeake Bay Program US. S. 794 Environmental Protection Agency. Annapolis, MD. 795 Stewart, Frank, Tim Mulholland, Alfred Cunningham, Bruce Kania, and Mark Osterlund. 2008. "Floating islands as 796 an alternative to constructed wetlands for treatment of excess nutrients from agricultural and municipal 797 wastes - Results of laboratory-scale tests." Land Contamination & Reclamation 16:25-33. doi: 798 10.2462/09670513.874. 799 Vázquez-Burney, R., J. Bays, R. Messer, and J. Harris. 2015. "Floating wetland islands as a method of nitrogen 800 mass reduction: results of a 1 year test." Water Sci Technol 72 (5):704-10. doi: 10.2166/wst.2015.235. 801 Wang, Chih-Yu, and David J. Sample. 2013. "Assessing floating treatment wetlands nutrient removal performance 802 through a first order kinetics model and statistical inference." Ecological Engineering 61:292-302. doi: 803 https://doi.org/10.1016/j.ecoleng.2013.09.019. 804 Yao, K. , S. Song, Zhang, Z. Xu , Zhang, J. Liu, L. Cheng, and J. Liu. 2011. "Vegetation characteristics and water 805 purification by artificial floating island " African Journal of Biotechnology 10 (82):19119-19125. doi: 806 DOI: 10.5897/AJB11.2964. 807 Zhu, Liandong, Zhaohua Li, and Tarja Ketola. 2011. "Biomass accumulations and nutrient uptake of plants 808 cultivated on artificial floating beds in China's rural area." Ecological Engineering 37 (10):1460-1466. doi: 809 https://doi.org/10.1016/j.ecoleng.2011.03.010.

810

230 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

811 FLUSHING, HYDRAULICS, AND DRAWDOWN

812 In-lake Prevention Strategy Substantial Supporting Data

813 It is well established that vertical water column stability and long water residence times favor 814 cyanobacteria over eukaryotic phytoplankton (Ibelings et al. 2016, Mitrovic et al. 2003, Paerl et 815 al. 2016); thus, the disruption of these conditions can, under certain circumstances, reduce 816 nuisance HCBs (Havens et al. 2019, Lehman 2014, McDonald and Lehman 2013). Management 817 strategies that change the hydraulics, increase flushing (i.e., shorter water retention time), or 818 decrease water levels can be effective management tools that not only affect nutrient delivery to 819 HCBs, but can disrupt the habitat conditions (i.e., calm warm water) that favor HCB 820 development in smaller water bodies (Paerl et al. 2016). The geographic setting of the water 821 body and lake depth will dictate which type of in-lake management strategy is feasible, based on 822 water availability or lack thereof. For example, arid western regions of the United States may 823 have more restrictions than eastern to midwestern regions.

824 In-lake hydraulics may be defined as the movement of water such as surface waves or internal 825 waves that are influenced by wind mixing, internal currents influenced by tributary inflows or 826 discharge, stratified water layers influenced by density gradients, or concentrations that affect 827 turbulent mixing within the water body (Starosolszky 1974). Disrupting seasonal stratification by 828 changing reservoir hydraulics can promote the development of diatom and green algae rather 829 than cyanobacteria.

830 Lake and reservoir flushing may be defined as the pass through of a large volume of water, 831 preferably lower in nutrient concentrations, with sufficient velocity to flush lake water 832 containing cyanobacteria downstream before the re-growth of cyanobacteria can occur in the 833 water body (Ibelings et al. 2016, Mitrovic, Hardwick, and Dorani 2010). Flushing reduces the 834 water retention time (Romo et al. 2012) and disrupts water column stability, thereby minimizing 835 the contact time between cyanobacteria and nutrients (Anderson, Komor, and Ikehata 2014). 836 Reservoir flushing may also be defined as the seasonal release of hypolimnetic water from 837 thermally stratified lakes that are enriched with bioavailable nutrients from internal nutrient 838 loading (Nürnberg 2007). The discharge of water before fall turnover reduces the amount of 839 nutrient-rich hypolimnetic water that mixes with near surface epilimnetic water and may reduce 840 cyanobacteria blooms that occur post-turnover.

841 The frequency of flushing flows may also affect the proliferation of benthic cyanobacterial mats 842 (Quiblier et al. 2013). Wood, Wagenhoff, and Young (2014) estimated the specific flushing 843 flows necessary to reduce Phormidium cover below 20% for multiple locations in New Zealand 844 rivers. A study across multiple New Zealand river systems demonstrated accrual of this 845 cyanobacterium also increased with time since the last flushing flow (McAllister et al. 2018). 846 Stanfield (2018) derived river discharge thresholds that, once exceeded, removed attached 847 benthic cyanobacteria in the upper Potomac River, Maryland.

848 Water level fluctuations (i.e., drawdown) may be defined as the lowering of the water level to 849 expose littoral zone habitat and sediments with the goal to switch the water body from a turbid, 850 algae-dominated system to a clear water, plant-dominated system (Scheffer et al. 1993).

231 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

851 However, the timing of the water level drawdown is critical, because summer-time drawdowns 852 can increase cyanobacteria production given the increased water retention time, increased water 853 temperature, and nutrients (Bakker and Hilt 2016). In shallow lakes, lower water elevations at 854 key times of the year may promote the growth of submerged and emergent macrophytes due to 855 increased light availability and reduce the potential for cyanobacteria development (Coops and 856 Hosper 2002, Scheffer and van Nes 2007). Mechanisms that indirectly affect cyanobacteria 857 development during drawdown include the disruption and loss of colonizable habitat for benthic 858 cyanobacteria (Turner et al. 2005), uptake of nutrients by macrophytes, the excretion of 859 allelopathic substances by macrophytes that may inhibit cyanobacteria growth (Hilt and Gross 860 2008), or development of macrophyte beds that support invertebrate and fish assemblages 861 (Bakker and Hilt 2016). In contrast, water level drawdown is often used in deeper lakes to reduce 862 aquatic nuisance plants and fish, and due to the timing of drawdown (e.g. winter), the strategy 863 generally limits the effectiveness of managing cyanobacteria blooms.

EFFECTIVENESS NATURE OF HCB • Flushing – low to moderately effective • Prevention strategy for: • Flushing: o Water body types: lake/reservoir o Effective on most types of cyanobacteria o Surface area: small, large in the epilimnion o Depth: shallow o Microcystis colonies in sheltered inlets o Trophic state: eutrophic or bays may be less affected by flushing o Mixing strategy: polymictic o Large releases of 80 MGD were o Requires more planning for water effective in suppressing Anabaena management circinalis o Reservoir releases of 80 MGD o In stratified lakes, flushing may not (million gallons per day) (critical affect cyanobacteria in the metalimnion flow velocity of 1 ft/s) have been o Flushing flows may reduce accrual of effective in mitigating HCB benthic cyanobacterial mats in rivers development via suppression of • Hydraulics: stratification and cell washout o Delay timing of occurrent for nitrogen- o Reservoir releases of 800 MGD have fixing (Aphanizomenon). non-nitrogen- been effective in removing an fixing taxa (Microcystis) established HCB o Change in algal composition favoring • Hydraulics – low to moderately effective diatoms for: • Drawdown: o Water body type: lake/reservoir. o More effective on benthic cyanobacteria o Surface area: small, large. (e.g. Planktothrix) o Run-of-river reservoir are more suitable for managing hydraulics given flow conditions. • Drawdown – low to moderately effective for: o Water body type: lake/reservoir o Surface area: small, large

232 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

864 Flushing management strategies have been moderately effective in eutrophic lake/reservoirs less 865 than 125 surface acres (Cross et al. 2014, James, Eakin, and Barko 2004, Pawlik-Skowronska 866 and Toporowska 2016), as well as in some larger reservoirs, provided sufficient flows are 867 available and the hydraulics are conducive (Qin et al. 2010). Releases of 80 MGD with a critical 868 flow velocity of 1 ft/s have been effective in mitigating HCB development in a large reservoir by 869 suppressing thermal stratification along with cell washout. Reservoir releases of 800 MGD have 870 been effective in removing an established HCB (Lehman 2014).

871 At Milford Reservoir in Kansas, which has a surface area of over 15,000 acres, the Management 872 Plan implemented since 2017 incorporates a spring drawdown that exposes a broad shallow area 873 in the upper portion of the water body; this is specifically designed to reduce habitat where 874 cyanobacterial blooms develop (USACE 2019).

ADVANTAGES LIMITATIONS • Variability in regional rainfall patterns may • Large volumes of low nutrient water are benefit flushing capability, influence water needed to flush a reservoir residence time and stratification, and • Expensive change cyanobacteria dominance and • Not practical or effective on larger persistence reservoirs • Horizontal flushing by increasing the flow • Drinking water or irrigation reservoirs through of water can reduce HCB generally do not have the luxury of water development via reduction in nutrient surplus for flushing supply • Requires more long-term planning to • Does not require capital/equipment coordinate flushing events investment • Changing reservoir hydraulics may warm • Weigh the cost of water versus intangible the bottom water, affecting cold water cost of closing water body due to HCBs fisheries • A series of reservoirs may be managed to • Drawdown may decrease shoreline stability store and release water for the benefit of and increase erosion and sediment flushing a downstream reservoir deposition • Numerical modeling may indicate that • Effectiveness of reservoir drawdown may changing reservoir hydraulics or flushing depend on sediment characteristics and the may or may not improve nutrient water potential for nutrient release from sediment quality or HCB conditions and macrophytes upon rewetting • Short pulses of water spread out over the • Potential for downstream impacts related to season may be as effective as one flushing HCBs and cyanotoxins during flushing event for planktonic species events • Run-of-the river reservoirs may lend better characteristics for the routing of water with bottom withdrawal to supplement convective-mixing and to reduce HCBs • Successive winter drawdowns may improve trophic conditions the following summer and reduce the potential for HCBs

233 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Figure 1: The benefit of high flow conditions on water column mixing, shorter retention times, and reducing HCB formation compared to low-flow conditions, longer retention times, and the persistence of thermal stratification that promote HCB formation

Figure Source: Paerl et al. 2016

875 Regional rainfall patterns may benefit flushing capability, influence water residence time, and 876 change cyanobacteria dominance and persistence (Jagtman, Van der Molen, and Vermij 1992, 877 Larsen et al. 2020). Other environmental factors such as thermal stratification, water 878 temperature, and the fishery should be considered before implementing this strategy (Fulton III 879 and Hendrickson 2011, Nelson et al. 2018). Often, numerical modeling can help evaluate these 880 environmental factors and determine whether changing the reservoir hydraulics or flushing will 881 be beneficial for the reservoir. The cost of raw water and limited supplies in many regions of the 882 US may also influence the decision to implement this lake management strategy, and in these 883 cases, the intangible cost (i.e., economics) of closing a water body due to HCBs should also be 884 considered.

885 COST ANALYSIS

886 Financial cost depends on site-specific, geographical settings and water availability. For 887 example, if hydroelectric facilities are associated with run-of-the river facilities, the financial 888 tradeoffs of water, electric power, and public perception must be thoroughly vetted before 889 hydraulic/flushing/drawdown management strategies are implemented. In the arid West, water 890 availability and the cost of water severely limit the feasibility of hydraulic/flushing strategies, 891 although water level drawdown may be more practicable in this region.

234 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

892 Table 1: Flushing, hydraulics, and drawdown CASE STUDY EXAMPLES 893 cost analysis per growing season. Ford Lake, Michigan, United States: In ITEM RELATIVE COST 2011, the selective withdrawal of PER GROWING hypolimnetic water at a rate of SEASON approximately 80 MGD reduced potential Water Availability $$ to $$$ power generation resulting in a revenue O&M Costs $$ to $$$ loss for the township of approximately $355 per day. Because Ford Lake is a run- Drawdown $ to $$ of-the river dam, a constant lake elevation OVERALL $$ to $$$ is maintained with the need to discharge 894 REGULATORY AND POLICY episodic rainfall events via the bottom 895 CONSIDERATIONS withdrawal outlet. If hypolimnetic anoxia occurred prior to the selective withdrawal, 896 Nearly all in-lake prevention/intervention then there would have been a greater risk 897 techniques, including flushing and water level downstream of poorer water quality or 898 drawdown, will require some form of potentially fish kills (Lehman 2014). 899 permitting or approval at the federal, state, or 900 local level (Holdren, Jones, and Taggart 2001). Despite the limitations on selective 901 Because these management strategies have the withdrawal given the dry/wet year type 902 potential to flush sediment, nutrients, conditions and the potential loss in power 903 cyanobacteria (cyanotoxins), and other generation revenue, elected officials 904 metalloid or hydrocarbon compounds to decided to continue the practice of selective 905 downstream regulated water bodies, as well as withdrawal which resulted in a revenue loss 906 affect streamflow and water availability of approximately $20,000 per year. The 907 downstream, the state water quality regulatory Township’s transparency in lake 908 office is the most appropriate agency to contact management decisions and the public’s 909 early in the planning phase. willingness to accept financial tradeoffs for benefits in water quality led to summer 910 Regulatory planning for withdrawals from 2009 – 2011 that reduced 911 hydraulic/flushing/drawdown techniques may cyanobacteria blooms during this period. 912 include but are not limited to Clean Water Act 913 Sections 401 or 404 permitting, NPDES The selective withdrawal of hypolimnetic 914 permitting, drawdown permitting, or water water enhanced the vertical mixing of the 915 rights administration and permitting. water column, limiting the cyanobacteria’s 916 Depending on the scale of the project and the preferred habitat in the epilimnion. The 917 extent of stakeholders, permitting could take Township explored other options including 918 months to years to obtain permission, so redesign of the hydroelectric facility to 919 planning is critical. Depending on the size of permit hypolimnetic power generation, but 920 the water body, its physical characteristics and the technical and capital investments 921 environmental setting, implementing these proved too costly. 922 techniques as short-term intervention Various locations: Bakker and Hill (2015) 923 approaches may require extensive planning. identify 13 case studies that illustrate key factors to consider when implementing this management tool to reduce or prevent cyanobacteria blooms. 235 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

924 REFERENCES

925 Anderson, Michael A., Andy Komor, and Keisuke Ikehata. 2014. "Flow routing with bottom withdrawal to improve 926 water quality in Walnut Canyon Reservoir, California." Lake and Reservoir Management 30 (2):131-142. 927 doi: 10.1080/10402381.2014.898720. 928 Bakker, Elisabeth S., and Sabine Hilt. 2016. "Impact of water-level fluctuations on cyanobacterial blooms: options 929 for management." Aquatic Ecology 50 (3):485-498. doi: 10.1007/s10452-015-9556-x. 930 Coops, Hugo, and S. Harry Hosper. 2002. "Water-level Management as a Tool for the Restoration of Shallow Lakes 931 in the Netherlands." Lake and Reservoir Management 18 (4):293-298. doi: 10.1080/07438140209353935. 932 Cross, Iain, Suzanne McGowan, T. Needham, and C. Pointer. 2014. "The effects of hydrological extremes on former 933 gravel pit lake ecology: Management implications." Fundamental and Applied Limnology / Archiv für 934 Hydrobiologie 185. doi: 10.1127/fal/2014/0573. 935 Fulton III, R. S., and J. C. Hendrickson. 2011. Relationships of Water Flow with Plankton and Water Quality In St. 936 Johns River Water Management District. Palatka, FL. 937 Havens, Karl E., Gaohua Ji, John R. Beaver, Rolland S. Fulton, and Catherine E. Teacher. 2019. "Dynamics of 938 cyanobacteria blooms are linked to the hydrology of shallow Florida lakes and provide insight into possible 939 impacts of climate change." Hydrobiologia 829 (1):43-59. doi: 10.1007/s10750-017-3425-7. 940 Hilt, Sabine, and Elisabeth Gross. 2008. "Can allelopathically active submerged macrophytes stabilise clear-water 941 states in shallow lakes?" Basic and Applied Ecology 9:422-432. doi: 10.1016/j.baae.2007.04.003. 942 Holdren, C. , W. Jones, and J. Taggart. 2001. Managing lakes and reservoirs. edited by U. S. Environmental 943 Protection Agency. Madison, WI: North American Lake Management Society ; Terrene Insitute,. 944 Ibelings, Bastiaan W., Myriam Bormans, Jutta Fastner, and Petra M. Visser. 2016. "CYANOCOST special issue on 945 cyanobacterial blooms: synopsis—a critical review of the management options for their prevention, control 946 and mitigation." Aquatic Ecology 50 (3):595-605. doi: 10.1007/s10452-016-9596-x. 947 Jagtman, E., D.T. Van der Molen, and S Vermij. 1992. " The influence of flushing on nutrient dynamics, 948 composition and densities of algae and transparency in Veluwemeer, The Netherlands." In Restoration and 949 Recovery of Shallow Eutrophic Lake Ecosystems in The Netherlands. Developments in Hydrobiology, 950 edited by L. Van Liere and R.D. Gulati. Dordrecht: Springer. 951 James, William F. , Harry L. Eakin, and John W. Barko. 2004. Limnological Responses to Changes in the 952 Withdrawal Zone of Eau Galle Reservoir, Wisconsin edited by U. S. Army Engineer Research and 953 Development Center. Vicksburg, MS. 954 Larsen, Megan L., Helen M. Baulch, Sherry L. Schiff, Dana F. Simon, Sébastien Sauvé, and Jason J. Venkiteswaran. 955 2020. "Extreme rainfall drives early onset cyanobacterial bloom." bioRxiv:570275. doi: 10.1101/570275. 956 Lehman, John T. 2014. "Understanding the role of induced mixing for management of nuisance algal blooms in an 957 urbanized reservoir." Lake and Reservoir Management 30 (1):63-71. doi: 10.1080/10402381.2013.872739. 958 McAllister, Tara G., Susanna A. Wood, Javier Atalah, and Ian Hawes. 2018. "Spatiotemporal dynamics of 959 Phormidium cover and anatoxin concentrations in eight New Zealand rivers with contrasting nutrient and 960 flow regimes." The Science of the total environment 612:71-80. doi: 10.1016/j.scitotenv.2017.08.085. 961 McDonald, Kahli E., and John T. Lehman. 2013. "Dynamics of Aphanizomenon and Microcystis (cyanobacteria) 962 during experimental manipulation of an urban impoundment." Lake and Reservoir Management 29 963 (2):103-115. doi: 10.1080/10402381.2013.800172. 964 Mitrovic, S. M., R. L. Oliver, C. Rees, L. C. Bowling, and R. T. Buckney. 2003. "Critical flow velocities for the 965 growth and dominance of Anabaena circinalis in some turbid freshwater rivers." Freshwater Biology 48 966 (1):164-174. doi: 10.1046/j.1365-2427.2003.00957.x. 967 Mitrovic, Simon M., Lorraine Hardwick, and Forugh Dorani. 2010. "Use of flow management to mitigate 968 cyanobacterial blooms in the Lower Darling River, Australia." Journal of Plankton Research 33 (2):229- 969 241. doi: 10.1093/plankt/fbq094. 970 Nelson, Natalie G., Rafael Muñoz-Carpena, Edward J. Phlips, David Kaplan, Peter Sucsy, and John Hendrickson. 971 2018. "Revealing Biotic and Abiotic Controls of Harmful Algal Blooms in a Shallow Subtropical Lake 972 through Statistical Machine Learning." Environmental Science & Technology 52 (6):3527-3535. doi: 973 10.1021/acs.est.7b05884. 974 Nürnberg, Gertrud K. 2007. "Lake responses to long-term hypolimnetic withdrawal treatments." Lake and 975 Reservoir Management 23 (4):388-409. doi: 10.1080/07438140709354026.

236 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

976 Paerl, H. W., W. S. Gardner, K. E. Havens, A. R. Joyner, M. J. McCarthy, S. E. Newell, B. Qin, and J. T. Scott. 977 2016. "Mitigating cyanobacterial harmful algal blooms in aquatic ecosystems impacted by climate change 978 and anthropogenic nutrients." Harmful Algae 54:213-222. doi: 10.1016/j.hal.2015.09.009. 979 Pawlik-Skowronska, Barbara, and Magdalena Toporowska. 2016. "How to mitigate cyanobacterial blooms and 980 cyanotoxin production in eutrophic water reservoirs?" Hydrobiologia 778 (1):45-59. doi: 10.1007/s10750- 981 016-2842-3. 982 Qin, B., G. Zhu, G. Gao, Y. Zhang, W. Li, H. W. Paerl, and W. W. Carmichael. 2010. "A drinking water crisis in 983 Lake Taihu, China: linkage to climatic variability and lake management." Environ Manage 45 (1):105-12. 984 doi: 10.1007/s00267-009-9393-6. 985 Quiblier, Catherine, Susanna Wood, Isidora Echenique, Mark Heath, Villeneuve Aurelie, and Jean-François 986 Humbert. 2013. "A review of current knowledge on toxic benthic freshwater cyanobacteria - Ecology, toxin 987 production and risk management." Water research 47. doi: 10.1016/j.watres.2013.06.042. 988 Romo, Susana, JUAN SORIA, FRANCISCA FERNÁNDEZ, YOUNESS OUAHID, and ÁNGEL BARÓN-SOLÁ. 989 2012. "Water residence time and the dynamics of toxic cyanobacteria." Freshwater Biology 58 (3):513- 990 522. doi: 10.1111/j.1365-2427.2012.02734.x. 991 Scheffer, M., S. H. Hosper, M. L. Meijer, B. Moss, and E. Jeppesen. 1993. "Alternative equilibria in shallow lakes." 992 Trends in Ecology & Evolution 8 (8):275-279. doi: https://doi.org/10.1016/0169-5347(93)90254-M. 993 Scheffer, Marten, and Egbert H. van Nes. 2007. "Shallow lakes theory revisited: various alternative regimes driven 994 by climate, nutrients, depth and lake size." Hydrobiologia 584 (1):455-466. doi: 10.1007/s10750-007- 995 0616-7. 996 Stanfield, Kevin. 2018. "DEVELOPING METHODS TO DIFFERENTIATE SPECIES AND ESTIMATE 997 COVERAGE OF BENTHIC AUTOTROPHS IN THE POTOMAC USING DIGITAL IMAGING." M. S. 998 Thesis, Environmental Biology, Hood College. 999 Starosolszky, Ö. 1974. "LAKE HYDRAULICS." Hydrological Sciences Bulletin 19 (1):99-114. doi: 1000 10.1080/02626667409493874. 1001 USACE. 2019. LAKE LEVEL MANAGEMENT PLANS WATER YEAR 2020. edited by Kansas Water Office: U. 1002 S. Army Corps of Engineers, Kansas City District. 1003 Wood, Susie, Annika Wagenhoff, and Roger Young. 2014. The Effect of River Flow and Nutrients on Phormidium 1004 Abundance and Toxin Production in Rivers in the Manawatu-Whanganui Region. Prepared for Horizons 1005 Regional Council.

1006

237 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1007 MIXERS, AERATORS, AND DIFFUSERS

1008 In-lake Prevention Strategy Substantial Supporting Data

1009 Hypolimnetic oxygenation/aeration and artificial mixing have been successfully used in lakes 1010 and reservoirs as physical controls to maintain oxygen levels in bottom waters while preserving 1011 thermal stratification and avoiding warming the hypolimnion (Beutel and Horne 1999, Bormans, 1012 Marsálek, and Jancula 2015, Visser et al. 2016). In the case of controlling HCBs, a hypolimnetic 1013 aeration/oxygenation system is designed to reduce concentrations of limiting nutrients, such as 1014 phosphorus, in the hypolimnion, with minimum mixing across the metalimnion to avoid the 1015 sudden introduction of nutrient-rich bottom waters into the epilimnion (Bormans, Marsálek, and 1016 Jancula 2015).

1017 Hypolimnetic oxygenation uses pure oxygen, whereas hypolimnetic aeration uses air to maintain 1018 oxygen levels and prevent the long-term storage of nutrients, encouraging natural cycling 1019 through the system rather than sudden entrainment into the epilimnion (Beutel and Horne 1999, 1020 Bormans, Marsálek, and Jancula 2015, Sahoo et al. 2015). There are several types of 1021 hypolimnetic oxygenation/aeration systems that slowly release oxygen or air using pumps, pipes, 1022 diffusers, or submerged chambers; various designs are available in Cooke et al. (2005). Systems 1023 are grouped into three categories: (1) mechanical agitation, (2) injection of pure oxygen, and (3) 1024 injection of air through a full lift or partial lift design or through a down-flow injection design 1025 (Cooke et al. 2005). The use of mixers, aerators, and diffusers to oxygenate a hypolimnion or 1026 induce artificial mixing is fundamentally different from the strategies that employ Nanobubbles 1027 and Ozonation, which induce synthetic biochemical reactions rather than reinforce inherent 1028 biological or physical processes.

1029 Artificial or mechanical circulation, also called de-stratification, is an engineering control aimed 1030 at keeping the bottom waters of lakes and reservoirs sustained with oxygen. This process 1031 completely mixes a stratified lake or reservoir, redistributing oxygen and nutrients throughout 1032 the water column (Hudson and Kirschner 1997). Generally, artificial mixing causes an increase 1033 in the oxygen content of the water, a temperature increase in the deep layers, and a temperature 1034 decrease in the upper layers, while increasing spatial phytoplankton distribution and 1035 concentration due to an increase in the limiting nutrient entrained from the hypolimnion or re- 1036 suspended from the sediments (Visser et al. 2016). The two most common types of de- 1037 stratification are air injection and mechanical mixing (Hudson and Kirschner 1997). Air injection 1038 is a "bottom-up" approach that quickly pumps air to the bottom of the lake so that it will rise and 1039 carry the water from the hypolimnetic layers to the top layer (Hudson and Kirschner 1997). 1040 Mechanical mixing uses a “top-down” approach wherein a rotating propeller in the surface layers 1041 pushes the water downward, displacing bottom waters to the surface where they are re- 1042 oxygenated by the atmosphere (Hudson and Kirschner 1997). Popular commercially available 1043 models are powered by solar panels. Although artificial circulation is beneficial for the purpose 1044 of oxygen and nutrient redistribution, the ecological effects on plant and animal life of 1045 destratifying a lake are not always predictable and could potentially be harmful (Hudson and 1046 Kirschner 1997).

1047 238 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

EFFECTIVENESS NATURE OF HCB • Water body type: lake/reservoir • Repeating HCB • Any surface area • Toxic and non-toxic HCB; effective for • Depth: deep; requires large hypolimnion, cyanotoxins avoid in shallow, unstratified systems • Targets all algal species • Any trophic state, but typically most • Prevention strategy effective in eutrophic systems • Mixing regime: meromictic, monomictic, or mimictic • Any water body use • Watershed loading levels will impact effectiveness

1048 These physical controls are most effective in systems that have or are expected to experience 1049 extensive, sustained nutrient and sediment loading and require remediation beyond periodic 1050 intervention strategies to protect the water quality and ecosystem (Bormans, Marsálek, and 1051 Jancula 2015). Often hypolimnetic oxygenation or mechanical mixing are used in conjunction 1052 with watershed controls and algaecide treatments (Bormans, Marsálek, and Jancula 2015, Moore 1053 and Christensen 2009, Visser et al. 2016). Physical oxygenation/aeration methods may not 1054 operate satisfactorily if the water body is too shallow even if stratification exists, as the density 1055 gradient may not be sufficient to resist thermocline attenuation while the hypolimnion is mixing 1056 (Bormans, Marsálek, and Jancula 2015). Physical oxygenation/aeration methods can cause a 1057 change in composition from cyanobacterial dominance to green algae and diatoms, if the water 1058 body is deep enough to limit light availability and the oxygenation/aeration devices are well 1059 distributed horizontally over the lake (Bormans, Marsálek, and Jancula 2015, Visser et al. 2016).

ADVANTAGES LIMITATIONS • No waste or byproducts produced • High installation costs • Readily available equipment • High operational costs associated with • Successful full-scale implementation year-round use • Reported water quality and ecological • Needs infrastructure (electricity, piping, benefits boat ramp, etc.) • Indiscriminate of algae species • Limited scalability • Minimal aesthetic impact • Potential water chemistry restrictions • Potential sediment chemistry restrictions • Potential adverse biological impacts

239 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1060

1061 Figure 1: (Left) Diffusive oxygenation schematic and (right) oxygen supply pipe and buoyancy 1062 pipe (from Gantzer et al. 2016).

1063 Many examples of hypolimnetic aeration applications in lakes and reservoirs worldwide have 1064 been reported in the literature, and extensive reviews include Beutel and Horne ((1999)), Cooke 1065 et al. (2005) and Singleton and Little (2007). Successful deployment of hypolimnetic 1066 oxygenation can delay stratification onset, establish a diatom population and allow it to persist 1067 longer, and remove limiting nutrients from the water column so that less nutrients are available 1068 in the epilimnion for cyanobacterial growth (Bormans, Marsálek, and Jancula 2015). 1069 Unsuccessful treatments that fail to mitigate HCBs are reported to have come from (1) aerators 1070 inadequately sized to account for increased biological oxygen demand (BOD) or such that they 1071 increase diffusion of the limiting nutrient into the epilimnion and result in enhanced 1072 cyanobacterial growth, (2) low availabilities of trace metals required for limiting nutrient 1073 fixation, (3) lack of external load control, and (4) lack of sufficient time of operation (Bormans, 1074 Marsálek, and Jancula 2015, National Research Council 2000). If these limitations are overcome, 1075 hypolimnetic aeration may reduce hypolimnetic nutrient accumulation and internal cycling, and 1076 ultimately reduce the development of HCBs.

1077 Adverse biological effects resulting from aeration have also been reported. The supersaturation 1078 of hypolimnetic water with N2 that might lead to a gas bubble disease in fish is a possible 1079 problem in some cases (Kortmann, Knoecklein, and Bonnell 1994). However, some biological 1080 and ecological benefits may also result from aeration. Aeration allows for deeper zooplankton 1081 distribution and refuge from predators in the dark bottom waters during the day (McComas 1082 2003). Additionally, the expanded aerobic environment may enhance growth and expansion of 1083 cold-water fish habitat and population due to increased oxygen concentrations, increased 1084 visibility, and greater zooplankton density (Rieberger and Section 1992).

1085 The following criteria are recommended by Bormans, Marsalek and Jancula (2015), in 1086 agreement with those proposed by Schauser, Lewandowski and Hupfer (2003) and Hickey and 1087 Gibbs (2009), and should be considered before choosing a physical oxygenation/aeration 1088 mitigation strategy:

1089 1. Define the critical limiting nutrient level needed to achieve the predicted outcome. 240 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1090 2. Assess the dynamics and relative role of internal loading compared to external loading. 1091 3. Assess the sediment characteristics to 1092 determine whether internal loading can CASE STUDY EXAMPLE 1093 be controlled. 1094 4. Quantify the link between internal load Newman Lake, Washington, United 1095 and cyanobacterial biomass. States: In the late 1960s and early 1970s, 1096 5. Scale the treatment as a function of the summer and fall blooms of cyanobacteria 1097 internal load and the size of the lake. began to occur in Newman Lake. Through 1098 6. Evaluate the potential to cause adverse the next decade, these blooms intensified 1099 effects to aquatic biota. and became an annual occurrence. A 1100 7. Set a long-term monitoring program Restoration Feasibility assessment of the 1101 before, during and after the treatment. lake and watershed indicated a major portion of phosphorus loading (∼83%) 1102 COST ANALYSIS was attributable to internal recycling associated with summer hypolimnetic 1103 The costs of installing and maintaining a 1104 oxygen depletion. In 1972, a Speece cone hypolimnetic oxygenation/aeration or artificial for hypolimnetic oxygenation was 1105 mixing system are relatively high, mostly due to 1106 installed, to supplement watershed operating costs associated with the generally controls and alum treatments. More details 1107 continuous mode of operation for successful 1108 are provided in Moore and Christensen applications, dependent on the type of (2009), 1109 equipment and local power rates (Bormans, 1110 Marsálek, and Jancula 2015). Increased Average summer volume-weighted total 1111 availability of solar power options may help phosphorus declined from pre-restoration 1112 mediate power costs. Aerators are usually levels exceeding 50 μg-P/L to an average 1113 installed in spring and run during the whole of 21 μg-P/L over 7 years. Most notably, 1114 summer (growing) season until autumn peak annual biovolumes of cyanobacteria 1115 (Bormans, Marsálek, and Jancula 2015). The and their representation within the 1116 costs associated with this method are not often phytoplankton community decreased 1117 reported in the literature. Costs of oxygen substantially, with increased prevalence of 1118 injection estimated by Hickey and Gibbs (2009) diatoms, green and golden-brown algae. 1119 were around $2.5 k/ha/yr, while Cooke et al. 1120 (2005) reported overall costs for an average of Overall, the response to nutrient reduction 1121 15 lakes in the USA of $3 k/ha/yr. A at Newman Lake is consistent with 1122 hypolimnetic aeration system installed in the worldwide observations that emphasize 1123 late 1990s in Amisk, Canada reported capital the need for long-term perspectives and 1124 costs of $30 k and operating costs of about $49 commitment in lake restoration and 1125 k/yr (Prepas and Burke 2011). Procedures for management. Continuation of internal 1126 sizing hypolimnetic aerators, and thus load controls and increased emphasis on 1127 determining lake-specific cost estimates, are external nutrient abatement have been 1128 described in detail by Lorenzen and Fast (1977), implemented to supplement positive water 1129 Ashley (1985) and Little (1995). Other quality trends, despite future development 1130 estimates can be found in Appendix 1 increases and land use changes. 1131 [hyperlink appendix].

241 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1132 Table 1: Mixers, aerators, and diffusers cost analysis per growing season.

1133 ITEM RELATIVE COST PER GROWING 1134 SEASON Material $$ 1135 Personal Protective $ Equipment 1136 Equipment $$$ Machinery $$$ 1137 Labor $$ 1138 O&M Costs $$$ OVERALL $$$ 1139

1140 REGULATORY AND POLICY CONSIDERATIONS

1141 A key component before implementation of a management action is to establish a cause-effect 1142 linkage between the problem and the proposed management approach (Hickey and Gibbs 2009, 1143 USEPA 2000). Recognizing that multiple stressors and environmental factors frequently 1144 combine to cause the effects observed in aquatic ecosystems, an integrated approach with 1145 multiple management measures is often required to address ecological issues in lakes 1146 holistically. The decision to introduce a hypolimnetic oxygenation system should be based on a 1147 thorough understanding of the factors at contributing to recurrent blooms and preliminary 1148 research to establish that an artificial oxygenation approach is a feasible option for reducing the 1149 frequency and severity of HCBs.

1150 Following Hickey and Gibbs (2009), the preliminary work would involve:

1151 1. Characterizing the main drivers likely to be responsible for the HCBs occurring in the lake. 1152 Specifically, information would be needed on: 1153 • The physical characteristics of the lake: 1154 o volume 1155 o depth 1156 o clarity 1157 o stratification 1158 o deoxygenation (including duration of anaerobic conditions) 1159 • Annual variation in the concentrations of major nutrients 1160 • Input/output budgets for the major nutrients 1161 • Annual changes in algal biomass and species 1162 • Information on geothermal inflows 1163 2. Determining the stratification classification and the potential for mixing of epilimnetic and 1164 hypolimnetic water; assessing whether the lake forms a stable stratification (USDA 1999). 1165 3. Determining that sediments will release nutrients under realistic conditions, particularly 1166 anaerobic conditions (sediment core measurements or hypolimnetic nutrient measurements). 242 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1167 4. Considering other potential treatment options to address internal nutrient loading, including: 1168 • hydraulic flushing 1169 • dredging of sediments 1170 • other source control measures

1171 This assessment must also include social and cultural values that need to be considered on a 1172 case-by-case basis with public and multi-agency consultation. The result of this consultation 1173 process may be concerns with a specific product or approach, and the selection and decision- 1174 making process may need to be modified accordingly. Any supplementary watershed controls or 1175 algaecide treatments must comply with policies and regulations as enacted by the appropriate 1176 oversight agency or authority. For some lakes, additional approval may be required from the US 1177 Fish and Wildlife Service and the National Oceanic and Atmospheric Administration's National 1178 Marine Fisheries Service under the Endangered Species Act (ESA) where endangered, 1179 threatened, or otherwise special status species are present, or the lakes are in conservation land 1180 (USFWS 2020). Special consideration for protection of native or indigenous species may be 1181 made.

1182 REFERENCES

1183 Ashley, Kenneth Ian. 1985. "Hypolimnetic aeration: practical design and application." Water Research 19 (6):735- 1184 740. doi: https://doi.org/10.1016/0043-1354(85)90120-4. 1185 Beutel, Marc W., and Alex J. Horne. 1999. "A Review of the Effects of Hypolimnetic Oxygenation on Lake and 1186 Reservoir Water Quality." Lake and Reservoir Management 15 (4):285-297. doi: 1187 10.1080/07438149909354124. 1188 Bormans, Myriam, Blahoslav Marsálek, and Daniel Jancula. 2015. "Controlling internal phosphorus loading in lakes 1189 by physical methods to reduce cyanobacterial blooms: a review." Aquatic Ecology 50. doi: 1190 10.1007/s10452-015-9564-x. 1191 Cooke, G., E. Welch, S. Peterson, and S. Nichols. 2005. Restoration and Management of Lakes and Reservoirs. 1192 Boca Raton: CRC Press. 1193 Hickey, Christopher W., and Max M. Gibbs. 2009. "Lake sediment phosphorus release management—Decision 1194 support and risk assessment framework." New Zealand Journal of Marine and Freshwater Research 43 1195 (3):819-856. doi: 10.1080/00288330909510043. 1196 Hudson, Holly, and Bob Kirschner. 1997. Lake Aeration and Circulation. edited by Illinois Environmental 1197 Protection Agency. Springfield, IL: Illinois Environmental Protection Agency. 1198 Kortmann, Robert W., George W. Knoecklein, and Charles H. Bonnell. 1994. "Aeration of Stratified Lakes: Theory 1199 and Practice." Lake and Reservoir Management 8 (2):99-120. doi: 10.1080/07438149409354463. 1200 Little, John C. 1995. "Hypolimnetic aerators: Predicting oxygen transfer and hydrodynamics." Water Research 29 1201 (11):2475-2482. doi: https://doi.org/10.1016/0043-1354(95)00077-X. 1202 Lorenzen, M. , and Fast. A. 1977. A GUIDE TO AERATION/CIRCULATION TECHNIQUES FOR LAKE 1203 MANAGEMENT. edited by U.S. Environmental Protection Agency. Washington, D. C. . 1204 McComas, Steve. 2003. Lake and pond management guidebook. Boca Raton, FL: Lewis Publishers. 1205 Moore, Barry C., and David Christensen. 2009. "Newman Lake restoration: A case study. Part I. Chemical and 1206 biological responses to phosphorus control." Lake and Reservoir Management 25 (4):337-350. doi: 1207 10.1080/07438140903172907. 1208 National Research Council. 2000. Clean Coastal Waters: Understanding and Reducing the Effects of Nutrient 1209 Pollution. Washington, DC: The National Academies Press. 1210 Prepas, E., and J. Burke. 2011. "Effects of hypolimnetic oxygenation on water quality in Amisk Lake, Alberta, a 1211 deep, eutrophic lake with high internal phosphorus loading rates." Canadian Journal of Fisheries and 1212 Aquatic Sciences 54:2111-2120. doi: 10.1139/f97-125. 1213 Rieberger, K., and BC Environment. Water Quality Section. 1992. Metal Concentrations in Fish Tissue from 1214 Uncontaminated B.C. Lakes: Water Quality Section. 243 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1215 Sahoo, G., Alexander Forrest, S. Schladow, J. Reuter, Robert Coats, and Michael Dettinger. 2015. "Climate change 1216 impacts on lake thermal dynamics and ecosystem vulnerabilities." Limnology and Oceanography 61:n/a- 1217 n/a. doi: 10.1002/lno.10228. 1218 Schauser, I., J. Lewandowski, and M. Hupfer. 2003. "Decision support for the selection of an appropriate in-lake 1219 measure to influence the phosphorus retention in sediments." Water Res 37 (4):801-12. doi: 1220 10.1016/s0043-1354(02)00439-6. 1221 Singleton, Vickie, and John Little. 2007. "Designing Hypolimnetic Aeration and Oxygenation Systems − A 1222 Review." Environmental Science & Technology 40:7512-20. doi: 10.1021/es060069s. 1223 USDA. 1999. A Procedure to Estimate the Response of Aquatic Systems to Changes in Phosphorus and Nitrogen 1224 Inputs. edited by National Water and Climate Center Natural Resources Conservation Service. Portland, 1225 OR: U. S. Department of Agriculture, Natural Resources Conservation Service, National Water and 1226 Climate Center. 1227 USEPA. 2000. Stressor Identification Guidance Document EPA 822-B-00-025. edited by Office of Water U. S. 1228 Environmental Protection Agency: U. S. Environmental Protection Agency, Office of Water. 1229 USFWS. 2020. "Endangered Species Laws and Policies." U. S. Fish and Wildlife Service, Ecological Services. 1230 https://www.fws.gov/endangered/laws-policies/regulations-and-policies.html. 1231 Visser, Petra M, Bas W Ibelings, Myriam Bormans, and Jef Huisman. 2016. "Artificial mixing to control 1232 cyanobacterial blooms: a review." Aquatic Ecology 50 (3):423-441.

1233

244 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1234 MONITORED NATURAL ATTENUATION

1235 In-lake Intervention Strategy Substantial Supporting Field Data

1236 HCBs go through natural growth and die-off cycles, often driven by seasons (Yamamoto and 1237 Nakahara 2009). If your community is disinclined to intervene in a bloom cycle with one or 1238 more active mitigation technologies and is instead interested in more passive and less costly 1239 strategies, then consider monitored natural attenuation (MNA) for the water body. MNA may be 1240 feasible for a HCB provided that exposure risks can be controlled. Even if a more active 1241 approach is preferred, in certain cases MNA may be the only practical option, for example, if the 1242 affected water body is too remote or too large to be cost-effectively treated through an imposed 1243 engineered solution. Similarly, if the HCB occurs late in the “growing season” or after the 1244 recreational season is over, there may not be support to invest the resources needed for active 1245 bloom treatment. On the other hand, if the water body is used as a drinking water source, MNA 1246 may not be an option (see Communication and Response Section).

1247 1248 Figure 1: Signage instructing citizens not to drink pond water.

1249 Source: Eric Roberts, 2019. Used with permission.

1250 MNA is fundamentally a risk management strategy. This means that stakeholders will need to be 1251 comfortable temporarily living with a controlled level of risk. It also means that the risks will 1252 need to be regularly reassessed as the character and toxicity of the bloom changes through its life 1253 cycle and as uses of and exposures to the water body evolves seasonally. Depending on 1254 stakeholder use of the affected water body, varying degrees of control measures may be needed 1255 to mitigate potential exposure pathways. For example, if the bloom-affected water is within a

245 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1256 sparsely populated residential community or remote, isolated areas, posting of warning signs 1257 along the shore may be adequate. However, in more densely populated communities, signage 1258 will probably need to be accompanied by reoccurring advertising in community publications, 1259 email distributions, webpages, homeowner association member portals, or newspapers. More 1260 concepts and approaches for keeping the public informed can be found in the Communication 1261 and Response chapter.

1262 A successfully and safely implemented MNA approach will likely include several key elements:

1263 1. Defining the problem – for example, by answering questions such as: What is the 1264 dominant cyanobacterium and can it be expected to attenuate as planned? Where is the 1265 bloom in the water column (surface scum or dispersed)? How does the dominant 1266 cyanobacterium respond to expected seasonal changes? Is it reasonable to expect the 1267 bloom will attenuate? Are cyanotoxins present? In what part of the growing season is the 1268 bloom occurring? 1269 2. Identifying and controlling exposure risks – for example, by answering questions such 1270 as: Is the lake a drinking water reservoir? Is the lake used for swimming? Is the lake used 1271 for fishing and, if so, is it “catch and release?” Is the lake in a remote location or in a 1272 populated area with domesticated animals? Do livestock have access to the water? Is 1273 wildlife exposure to the bloom a concern? Can signage and other communication tools be 1274 expected to adequately inform the public? Is the bloom occurring during the recreational 1275 season? Are there other news or social media means of effectively communicating 1276 exposure risks to the community? 1277 3. Monitoring the bloom and protective controls – for example, by regularly collecting 1278 the information needed to answer questions such as: How are cyanobacteria counts 1279 changing? What changes are occurring in dominant cyanobacteria species? Are 1280 cyanotoxins being produced and, if so, are the cyanotoxins at levels of concern? Is the 1281 bloom causing any unforeseen problems? Are there indications the bloom will not 1282 attenuate when expected? Is signage being maintained? Are public notices/other 1283 communications continuing? Is the public adhering to advisories? Is public sentiment 1284 changing? Bloom monitoring generally includes tracking cyanobacteria population 1285 densities, species prevalence, and presence and concentrations of toxins. A sequential 1286 approach is recommended by USEPA (2019) to monitor blooms. Initially, visual 1287 indications of bloom formation and growth may be evaluated by field instrument scans of 1288 levels of chlorophyll and phycocyanin. Visual and field analytical indications of bloom 1289 formation or expansion may then be further assessed by laboratory phytoplankton 1290 identification and counts of cyanobacteria. Elevated cyanobacteria abundances may 1291 trigger subsequent testing for and quantification of cyanotoxins. 1292 4. Planning for contingencies – for example, by having plans in place that address 1293 questions such as: What active remedies will be considered if MNA ceases to be viable? 1294 Is funding in place in case an alternative to MNA needs to be implemented? Have 1295 vendors, suppliers, or other resources been identified in case active treatment becomes 1296 necessary?

1297

246 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

EFFECTIVENESS NATURE OF HCB • Water body types: pond, lake/reservoir, • Surface or sub-surface HCB bay/estuary • Toxic and non-toxic HCB • Surface area: shallow • Almost any area except perhaps a drinking • Depth: deep water source • Any mixing regime • Intervention strategy • Confined to bloom area • Dissipation may occur through natural cycles 1298

ADVANTAGES LIMITATIONS • Low cost relative to active, engineered • May or may not yield a bloom decline (Van remedies den Wyngaert et al. 2011) • No expertise, infrastructure, or special • Substantial staff time for signage, outreach, equipment required and monitoring • No chemical additives nor physical • Requires outreach to local residents and manipulations lake users for threat, aesthetics of the water, • No wastes or by-products recreational limits • Untreated nascent or resident cyanobacteria populations may re-seed the water body (Preston, Stewart, and Reynolds 1980) • Recurrent monitoring is often needed to reassess risks

1299 COST ANALYSIS

1300 The primary costs are for producing and distributing outreach materials, signage for local water 1301 body users and labor for posting / removing signs, and monitoring water quality conditions. In 1302 addition to monitoring during an active bloom event, some monitoring should also be considered 1303 to document bloom dissipation or not.

1304 Table 1: Monitored natural attenuation cost analysis per growing season.

ITEM RELATIVE COST PER GROWING SEASON Material - Personal Protective Equipment - Equipment - Machinery - Tools - Labor $ O&M Costs $ Occasional Monitoring $ TOTAL $ 247 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1305 REGULATORY AND POLICY CONSIDERATIONS

1306 If the water body is a public water supply source, the municipal authority or water purveyor may 1307 need to actively treat the lake HCB rather than to take the MNA approach. For treatment, 1308 regulatory approvals or permits may be needed. However, careful consideration and planning 1309 should precede selecting MNA, including soliciting input from the stakeholders and securing 1310 public consensus.

1311 REFERENCES

1312 Preston, T., W. D. P. Stewart, and C. S. Reynolds. 1980. "Bloom-forming cyanobacterium Microcystis aeruginosa 1313 overwinters on sediment surface." Nature 288 (5789):365-367. doi: 10.1038/288365a0. 1314 USEPA. 2019. Recommendations for Cyanobacteria and Cyanotoxin Monitoring in Recreational Waters EPA 823- 1315 R-19-001. edited by Office of Water U. S. Environmental Protection Agency. 1316 Van den Wyngaert, Silke, Michaela M. Salcher, Jakob Pernthaler, Michael Zeder, and Thomas Posch. 2011. 1317 "Quantitative dominance of seasonally persistent filamentous cyanobacteria (Planktothrix rubescens) in the 1318 microbial assemblages of a temperate lake." Limnology and Oceanography 56 (1):97-109. doi: 1319 10.4319/lo.2011.56.1.0097. 1320 Yamamoto, Yoshimasa, and Hiroyuki Nakahara. 2009. "Life Cycle of Cyanobacterium Aphanizomenon flos- 1321 aquae." Taiwania 54. doi: 10.6165/tai.2009.54(2).113. 1322

248 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1323 NANOBUBBLING

1324 In-lake Intervention and Prevention Strategy Emerging Supporting Field Data

1325 Air, oxygen, or ozone pumped under low pressure through a fine pore carbon ceramic plate and 1326 into flowing water induces nanobubble formation and dispersal into receiving waters. True 1327 nanobubbles are <100 nm in diameter, dense, and sink to the bottom. They may persist for weeks 1328 to months. Nanobubbling is in contrast to any bubbling or aeration technique wherein bubbles 1329 are visible or rise to the surface. In selecting a bubbling technique, if nanobubbling is offered, 1330 ask to see the dispersal in your water body: if bubbles are visible, the technique is not 1331 nanobubbling and will not provide the oxidation of cyanobacteria that nanobubbling could 1332 provide. Larger, visible bubbles will aerate and destratify water bodies, which can be a good 1333 option for HCB control, but it does not kill the cyanobacteria (for more detail on aeration and 1334 diffusers, see the Mixers, Aerators, and Diffusers strategy).

1335 Dispersed nanobubbles eventually collapse to release hydroxyl free radicals, strong oxidizing 1336 agents that act as an effective bactericide (Tsuge et al. 2009); ozone is the most potent oxidizer 1337 used with air least. However, all suggest potential efficacy for cyanobacteria control. Several 1338 unpublished white papers and reports indicate large reductions in planktonic chlorophyll 1339 concentrations from nanobubble introduction, at least one in a cyanobacteria-dominated water 1340 body (NBS 2018b); however, there are no replicated data, nor has the report been peer reviewed, 1341 so the technique must be considered as an emerging strategy.

Figure 1: Field unit for nanobubble generation and dispersal in the field (NBS 2018b). Note dispersal can also be undertaken through hoses at the surface.

249 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1342 Nanobubbling duration is scalable, with bubbling time dependent on water body size and goal 1343 for the system, e.g. re-oxygenation, removing surface scums, or reducing water column 1344 chlorophyll while still protecting fish. Results from several recent field projects (NBS 2018b, a) 1345 indicate that bottom mud organic matter is oxidized, shifting muds from anaerobic to aerobic 1346 systems. This reduces the release of nitrogen and phosphorus from bottom sediments, reducing 1347 the internal nutrient supplies that support overlying algal and cyanobacterial growth. Dissolved 1348 oxygen concentrations increase in the water column and the few data collected indicate 1349 substantial short-term reductions in planktonic chlorophyll. 1350 EFFECTIVENESS NATURE OF HCB • Water body types: pond, lake/reservoir, • All HCB types bay/estuary • Prevention and intervention strategy • Any surface area or depth; small-to-large systems have been improved • Trophic state: most effective in organic-rich systems • Any water body use • Best in systems with moderate to long residence times • Can prevent expected or reduce ongoing blooms with increase in free oxygen radicals • Long bubble life ensures reoxygenation over a long period, including bottom sediments

1351 The current technology can be conducted using mobile (10 or 20 ft box truck) or fixed (onshore 1352 or floating surface stations) nanobubble generators and is effective most rapidly using ozone (see 1353 Ozonation [LINK]), then oxygen, then air generators. Electricity or solar power is needed; larger 1354 generating systems use substantial power, while smaller ponds or lakes could be treated with 1355 solar power.

ADVANTAGES LIMITATIONS • No waste products • Bottom sediments and water column are • Rapid and several month persistence of oxygenated but water body size and nanobubbles ensures aerobic conditions for duration of improved conditions unknown long periods • Needs electricity, water access for • Reduces nutrient flux from nanobubble- deploying nanobubble hoses produced aerobic bottom sediments • Destruction of toxins unknown but may • Aerobic sediments induce recolonization by occur bottom animals • At low nanobubble levels, cyanobacteria • Scalable may be susceptible with algae more • In contrast to microbubbles which release resistant their gas content quickly, nanobubbles • Oxidation will temporarily increase available nutrient supplies through release

250 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

reportedly remain for weeks to months, of nitrogen and phosphorus from oxidized thereby providing long-term impact organic matter • Permits may be required

1356 COST ANALYSIS CASE STUDY EXAMPLES

1357 Within-growing season costs are estimated Asia and United States: The current 1358 below and will depend on size of the water nanobubble technology (i.e., bubbles <100 1359 body, organic matter present, and labor. nm) has been applied in 5-10 projects throughout these regions but unfortunately 1360 Table 1: Nanobubbling cost analysis per even though improvements in water quality 1361 growing season. were achieved (e.g., increased water clarity, ITEM RELATIVE COST declines in planktonic chlorophyll, a shift in PER GROWING bottom sediment systems from anaerobic to SEASON aerobic conditions, return of aerobic bottom Material $$ fauna), the absence of sample replication in Personal Protective $ these projects prevents inclusion of the Equipment strategy as a confirmed field mitigation strategy at this time. Equipment $$$ Machinery $ To resolve effectiveness of the technology Tools $ on bloom-forming algae and cyanobacteria, Labor $$ laboratory nanobubble exposure experiments O&M Costs $$ are underway with freshwater HCB species Monitoring $ as well as marine HAB taxa. Monitoring protocols for field projects should include OVERALL $$ multiple replicates for all field parameters 1362 likely to change from nanobubble treatment. 1363 1364

1365 REGULATORY AND POLICY CONSIDERATIONS

1366 Permits may be required for nanobubble dispersal and type of gas (air, oxygen, ozone) used. 1367 There may be additional safety concerns when using concentrated ozone. Short-term aesthetic 1368 issues during treatment disappear following treatment. Outreach to residents regarding placement 1369 of mobile or permanent bubble generator should be undertaken.

1370 REFERENCES

1371 NBS, (Nanobubble Solutions LImited). 2018a. Project to Eliminate Blue-Green Algae at the Outer Moat of the 1372 Imperial Palace Hibiya, Tokyo: Project Overview Japan. 1373 NBS, (Nanobubble Solutions LImited). 2018b. 1374 Tsuge, Hideki, Pan Li, Naotaka Shimatani, Yuki Shimamura, Hideo Nakata, and Michio Ohira. 2009. "Fundamental 1375 Study on Disinfection Effect of Microbubbles." KAGAKU KOGAKU RONBUNSHU 35 (5):548-552. doi: 1376 10.1252/kakoronbunshu.35.548.

251 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1377 NANOPARTICLES (IRON-BASED)

1378 In-lake Intervention Strategy Limited/Emerging Supporting Field Data

1379 Several studies were reviewed that focused on iron-based nanoparticles and their ability to 1380 adsorb cyanobacteria and degrade cyanotoxins through oxidative transformation. The technology 1381 is used in remediating and treating water, wastewater, and groundwater (Kharisov et al. 2012). 1382 No open-water case-studies for HCB management were found. Zero-valent iron (nZVI) and 1383 bimetallic nanoparticles (Fe-Ni and Fe-Pd) can degrade microcystin-LR (MC-LR) in drinking 1384 water treatment, with Fe-Pd showing the greatest degradation of MC-LR over the broadest pH 1385 range (~95% removal) (Gao et al. 2016). This treatment has also been used for several other 1386 microcystin congeners and cylindrospermopsin. Other metallic/elemental compounds in some 1387 nanoparticles include TiO2, Ni-Pd, polypyrrole, graphene, carbon, silver, and silica.

EFFECTIVENESS NATURE OF HCB • Unknown in any field application • Effective at pH 7 for microcystin-LR, -LA, - YR and at pH 9 for MC-RR and cylindrospermopsin • Use is limited to drinking water • Intervention strategy 1388

ADVANTAGES LIMITATIONS • Quick reaction time • No field applications • Readily adsorbs and destroys many • nZVI has poor performance but effective contaminants, including cyanotoxins with other metal ions included • Some by-products promote flocculation • May bind other compounds before • Can utilize magnetic particles cyanotoxins • Possible re-use • Unknown long-term environmental impact • Re-used particles only 30-40% effective after 8 times

252 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1389 COST ANALYSIS CASE STUDY EXAMPLES 1390 Cost information is scarce due to the recent 1391 Laboratory-scale: Use of nZVI and development of the technology and the limited bimetallic nanoparticles (Fe-Ni & Fe-Pd) to 1392 commercialization of the products (Adeleye et 1393 degrade microcystin-LR (MC-LR) in al. 2016). drinking water. Fe-Pd showed the greatest degradation of MC-LR (~95% removal) with 1394 Table 1: Nanoparticles cost analysis per the broadest pH range. Ni and Pd act as a 1395 growing season. catalyst for the degradation of MC-LR, ITEM RELATIVE COST whereas nZVI alone tends to readily form PER GROWING iron oxides and hydroxides in water, SEASON reducing its surface reactivity with MC-LR Material $-$$ (Gao et al. 2016). Personal Protective UNKNOWN Highest adsorption rate for microcystin-LR, - Equipment LA, and -YR was at pH 7, whereas highest Equipment UNKNOWN rate for MC-RR and cylindrospermopsin was Machinery UNKNOWN at pH 9. Removal from potable water using Tools UNKNOWN magnetophoretic nanoparticles of Labor UNKNOWN polypyrrole. Adsorption capacity dropped to O&M Costs UNKNOWN 30-40% after reusing eight times. Polypyyrole/Fe O had a high potential to Etc. UNKNOWN 3 4 remove cyanotoxins and could potentially be OVERALL >$$ a cost-effective solution based on its 1396 reusability (Hena et al. 2016). 1397 REGULATORY AND POLICY Adeleye et al. (2016) note there is still the 1398 CONSIDERATIONS likely persistence of some nanomaterials in the environment after use and suggest 1399 Long-term toxicity of nanoparticles in the research is also needed to focus on predicting 1400 environment is unknown, which may limit the nanocomposite toxicity so each new particle 1401 scope of use or release into the environment. does not have to be individually tested. 1402 These materials are considered emerging 1403 contaminants by USEPA (2014). There are 1404 federal and/or local regulations based on 1405 intended use and application area.

1406 REFERENCES

1407 Adeleye, Adeyemi S., Jon R. Conway, Kendra Garner, Yuxiong Huang, Yiming Su, and Arturo A. Keller. 2016. 1408 "Engineered nanomaterials for water treatment and remediation: Costs, benefits, and applicability." 1409 Chemical Engineering Journal 286:640-662. doi: https://doi.org/10.1016/j.cej.2015.10.105. 1410 Gao, Ying, Feifeng Wang, Yan Wu, Ravendra Naidu, and Zuliang Chen. 2016. "Comparison of degradation 1411 mechanisms of microcystin-LR using nanoscale zero-valent iron (nZVI) and bimetallic Fe/Ni and Fe/Pd 1412 nanoparticles." Chemical Engineering Journal 285:459-466. doi: https://doi.org/10.1016/j.cej.2015.09.078.

253 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1413 Hena, S., R. Rozi, S. Tabassum, and A. Huda. 2016. "Simultaneous removal of potent cyanotoxins from water using 1414 magnetophoretic nanoparticle of polypyrrole: adsorption kinetic and isotherm study." Environ Sci Pollut 1415 Res Int 23 (15):14868-80. doi: 10.1007/s11356-016-6540-5. 1416 Kharisov, Boris I., H. V. Rasika Dias, Oxana V. Kharissova, Victor Manuel Jiménez-Pérez, Betsabee Olvera Pérez, 1417 and Blanca Muñoz Flores. 2012. "Iron-containing nanomaterials: synthesis, properties, and environmental 1418 applications." RSC Advances 2 (25):9325-9358. doi: 10.1039/C2RA20812A. 1419 USEPA. 2014. Technical Fact Sheet - Nanomaterials EPA 505-F-14-002 edited by Office of Solid Waste and 1420 Emergency Response U. S. Environmental Protection Agency. Washington, D. C.: U. S. Environmental 1421 Protection Agency, Office of Solid Waste and Emergency Response.

1422

254 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1423 ORGANIC BIOCIDES

1424 In-lake Intervention Strategy Limited/Emerging Supporting Field Data

1425 Several research groups have explored the possibility of controlling cyanobacterial blooms using 1426 natural biocidal compounds or synthetic analogs. These compounds are not one group, or a 1427 derivate of a similar group or classification of molecules; but instead represent natural or 1428 synthetically modified extracts from various sources. By definition, a biocide is any compound 1429 (preservative, insecticide, disinfectant, pesticide, herbicide, fungicide, etc.) that is used for 1430 controlling a microorganism that is harmful to human or animal health (USEPA 2019). These 1431 organic biocides can range in their various algal and cyanobacterial targets, and there is an 1432 extensive literature of possible ecological endpoints. In some cases, it is not known how these 1433 compounds function, instead only observations of the various effects (algistatic/algaecidal) these 1434 biocides may have on target organisms are available. In some cases, compounds registered as 1435 biocides with the USEPA for the control of cyanobacteria are used for limited instances such as 1436 industrial cooling waters and biofouling, and not for surface recreational water bodies.

1437 In general, organic biocides can be broken down into two categories, those that are extracted 1438 from plants and those that are natural derivatives of specific metabolites of various other 1439 microorganisms or plants (NIEWPCC 2015). One potential good example of a commonly used, 1440 known natural biocide is the extracts of barley straw, which are expanded upon further in its own 1441 section (Barley straw [LINK]).

EFFECTIVENESS NATURE OF HCB • Depending on the biocide and application, • Since this is not a homogeneous group of it can vary compounds, the nature of the HCB will vary by the product. For USEPA approved products, follow the application guidance for the nature of the HCB bloom experienced • Intervention strategy

1442 Various natural compounds have been considered for their potential activity against 1443 cyanobacterial blooms and cyanotoxins. While this is not an exhaustive list, several candidates 1444 have been examined by various groups previously (NIEWPCC 2015). A list of the potentially 1445 most common organic biocides is included at the end of this review. These compounds generally 1446 are investigated in small scale studies and broader ecological impacts may not be known or fully 1447 understood. Exhaustive reviews of natural compounds, such as those conducted by Shao et al, 1448 (2013) note that many of these compounds may only be weakly cyanocidal or only exhibit 1449 inhibitory effects at very high concentrations. Additional concerns are that some organic biocide 1450 compounds can themselves be sources of N or P; and documented use of some of these 1451 compounds, such as L-lysine may enhance eutrophication by introducing exogenous sources of 1452 nitrogen.

1453

255 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1454 COMMONLY REFERENCED BIOCIDES

1455 1. Barley Straw / Barley Straw Extracts 1456 2. L-Lysine 1457 3. Tellimagrandin Ⅱ 1458 4. Tryptamine 1459 5. Nonanoic acid 1460 6. β-ionone 1461 7. Geranyl acetone

ADVANTAGES LIMITATIONS • Cost can be lower, depending on the • Limited documented application for all organic biocide and the source, compared organic biocides as an intervention to chemical algaecides technique for HCBs • Some extracts can be prepared on site • Depending on mechanism of action, with minimal equipment cyanotoxin release can occur • Some natural compounds may degrade • Some risk of enhancing eutrophication in with no off-target effects noted the use of some compounds • Human and animal toxicity data are limited for many of these compounds • High purity extracts may be cost prohibitive to be used effectively to control blooms

256 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1462 COST ANALYSIS CASE STUDY EXAMPLES 1463 Estimating cost is difficult for this technique 1464 Dianch Lake, China: The cyanocidal effects due to the numerous variables which can be of L-lysine and malonic acid were evaluated 1465 factored in. The cost and difficulty of the 1466 in enclosures with blooms of Microcystis generating the compound is a limiting factor, aeruginosa (Kaya et al. 2005). 1467 as is “growing” the source material. Some 1468 material, such as L-lysine, can be extracted in Three enclosures, measuring 10 m x 10 m x 1469 abundance at low cost, and others as described 1.5 -1.3 m depth were established and 1470 in the literature require several purification monitored over 28 days. Enclosure “A” 1471 stages to get to the targeted compound. In served as the control, “B” served as L-lysine 1472 general, the simpler the extraction method the alone, and “C” served as L-lysine + malonic 1473 lower the cost. acid. 1474 Some specialized equipment such as sprayers Upon initial spraying, blooms resolved in 1475 or on-site grinders may need to be purchased if both enclosures B and C; however, within 7 1476 the extract needs to be performed fresh. days a rebound bloom of M. aeruginosa appeared in enclosure B. 1477 Table 1: Organic biocides cost analysis per 1478 growing season. No rebound bloom was documented in enclosure C, and enhanced macrophyte ITEM RELATIVE COST growth was observed. PER GROWING SEASON By the end of 28 days no recovery of L- Material $-$$$ lysine or malonic acid could be detected, Personal Protective indicating that possible complete $-$$ Equipment degradation of these compounds had Equipment $-$$ occurred. Labor $ O&M Costs $ OVERALL $$

1479 REGULATORY AND POLICY CONSIDERATIONS

1480 Some organic biocides already have USEPA registration and additional products are registered 1481 as organic biocides, but in controlled environments. Some products, though naturally derived, 1482 have not been evaluated for short or long-term toxicity in humans or other aquatic organisms and 1483 may pose a hazard. A “natural” or “organic” product does not mean that it is safe or will not have 1484 greater impacts on the ecosystem than the HCB that the product is purported to treat.

1485 REFERENCES

1486 Kaya, K., Y. D. Liu, Y. W. Shen, B. D. Xiao, and T. Sano. 2005. "Selective control of toxic Microcystis water 1487 blooms using lysine and malonic acid: an enclosure experiment." Environ Toxicol 20 (2):170-8. doi: 1488 10.1002/tox.20092. 1489 NIEWPCC, (New England Interstate Water Pollution Control Commission). 2015. "Harmful Algal Bloom Control 1490 Method Synopsis." 257 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1491 Shao, J., R. Li, J. E. Lepo, and J. D. Gu. 2013. "Potential for control of harmful cyanobacterial blooms using 1492 biologically derived substances: problems and prospects." J Environ Manage 125:149-55. doi: 1493 10.1016/j.jenvman.2013.04.001. 1494 USEPA. 2019. "I-BEAM Glossary of Terms." U. S. Environmental Protection Agency. 1495 https://ofmpub.epa.gov/sor_internet/registry/termreg/searchandretrieve/glossariesandkeywordlists/search.d 1496 o?details=&vocabName=I-BEAM%20Glossary%20of%20Terms.

1497

1498 .

258 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1499 OZONATION

1500 In-lake Intervention Strategy Limited Supporting Field Data

1501 Ozonation is an advanced oxidation technique that works by infusing ozone gas into water and 1502 has a long history of substantial process level use for the disinfection of drinking water and 1503 wastewater (Loeb et al. 2012, Rice 1991). Ozone attacks the chemical bonds within cyanotoxins 1504 and other compounds, leading to rapid degradation. Ozone treatment requires onsite generation 1505 of ozone gas, due to a short half-life of the compound. In general, ozone is produced by passing 1506 purified air through an electric discharge to convert oxygen to ozone. Ozone is not readily 1507 soluble in water, particularly compared to other oxidative compounds such as chlorine, so it 1508 requires a delivery mechanism such as a diffuser for application. Application methods vary but 1509 do require onsite infrastructure for application. Ozonation has substantial documentation for 1510 applications in both drinking water and wastewater processing, and ozone nanobubbles (see 1511 Nanobubbling [LINK]) have been used in ponds, lakes, and bays to reduce planktonic 1512 chlorophyll concentrations. It is also a fourth step in the surfactant-air flotation-skimming- 1513 ozonation technique described in the Skimming and Harvesting [LINK] strategy.

1514 Except for non-replicated ozone nanobubble projects in Asia and Florida, ozonation is still a 1515 research technique for the treatment of HCBs in surface waters, with no current peer-reviewed 1516 literature on surface water treatment. Ozonation has been shown to oxidize multiple cyanotoxin 1517 classes (Newcombe and Nicholson 2004). For example, pilot and laboratory work suggests that 1518 significant reductions in microcystin concentrations can be achieved with an ozone concentration 1519 of at least 0.3 mg/L and a contact time of at least 5 minutes. Similar results were also observed 1520 for anatoxin-a at somewhat higher ozone concentrations (Newcombe and Nicholson 2004). The 1521 amount of dissolved organic carbon in the water strongly affects the efficacy of ozone treatment 1522 on cyanotoxins (Staehelin and Hoigne 1985). Ozonation also shows promise in killing HCB 1523 organisms directly and has been shown experimentally to lyse cells of several genera including 1524 Microcystis spp., Dolichospermum spp., Aphanizomenon spp., and Pseudanabaena spp. (Pandhal 1525 et al. 2018, Zamyadi et al. 2015)

EFFECTIVENESS NATURE OF HCB • Water body type: pond, lake/reservoir • Useful in for drinking water treatment for • Water body uses: drinking water, treated reservoirs and other source waters with wastewater/effluent chronic blooms • Can kill Microcystis spp. and other cells with sufficient contact time • Intervention strategy 1526

259 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

ADVANTAGES LIMITATIONS • Ozone treatment in benchtop applications • Ozone treatment is likely not suitable for a has been shown to be capable of one-time application as it needs to be completely oxidizing multiple cyanotoxin generated on site classes including microcystins, anatoxin-a, • Ozone treatment has an extremely high and cylindrospermopsin. It has not been oxidation potential and is non-selective in shown to oxidize saxitoxins efficiently the organisms that are killed (both HCB (Cheng et al. 2009, Fawell et al. 1993, and non-HCB organisms) Newcombe and Nicholson 2004, Onstad et • Ozone treatment generally results in cell al. 2007, Rositano et al. 2001). lysis, which could release cyanotoxins • Ozonation has also been shown to have the contained within HCB cells ability to lyse cells, with the effectiveness • The effectiveness of ozone treatment is depending on the ozone concentration and impacted by the concentration of organic contact time matter in the system; therefore, it may • Ozone also removes many other water require pre-treatment if organic matter impurities including taste and odor loads are high compounds (Ho, Newcombe, and Croué • Ozone treatment does not leave residuals; 2002), Cryptosporidium, and many other therefore, treatment is short-lived and organic compounds requires reapplication • If metal content of the water is high, ozonation will form insoluble metal oxides that potentially would need to be removed

1527 Treatment of HCB events in surface water via ozonation is still in development. It has been 1528 applied in several field situations via dispersal of ozone nanobubbles to reduce planktonic 1529 chlorophyll concentrations (without any species information however), so ozonation remains an 1530 emerging strategy as it is still largely a research technique. Consult Nanobubbling [LINK] for its 1531 costs with respect to ozonation.

260 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1532 COST ANALYSIS CASE STUDY EXAMPLE

1533 Large scale use of ozone is estimated to be the Laboratory-scale: Pandhal et al. (2018) 1534 most expensive of the advanced oxidation conducted a benchtop study using a novel 1535 processes according to a cost analysis conducted ozone generation and application method. 1536 by Dore et al. (2013) for smaller systems. The study used a low temperature plasma 1537 Primary expenses are capital costs, which can be dielectric barrier discharge reactor and a 1538 in the millions, and hundreds of millions of fluidic oscillator diffuser, which has 1539 dollars for yearly operational costs. Dore et al. lower energy requirements than other 1540 (2013) estimated that ozone treatment could cost systems. Together this method delivers 3 1541 between $0.10 - $0.50/ m water, with costs ozone in microbubbles, which increases 1542 decreasing precipitously at treatment volumes the solubility of ozone and therefore 3 1543 >10,000 m /d. increases the contact time. 1544 This study showed that microbubble delivery of ozone via this system rapidly 1545 Table 1: Ozonation cost analysis per growing degrades microcystins, with complete 1546 season. oxidation of MC-LR in 2 minutes at an ozone flow rate of 1 L/min. Importantly, ITEM RELATIVE COST the treatment showed a large decrease in PER GROWING toxicity of the microcystin, with the SEASON microcystin by-products showing a Material $$$ substantial decrease in inhibitory activity. PPE $$ Lysis of Microcystis aeruginosa cells was Equipment $$$ observed within 20 minutes. Machinery $$$ Tools $$$ Alternative ozone generation/delivery Labor $$$ technologies such as described in Pandhal O&M Costs $$$ et al. (2018) have the potential to lower TOTAL $$$ the operation costs of ozonation making the treatment more affordable in the future.

261 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1547

1548 Figure 1. From Dore et al. (2013).

1549 REGULATORY AND POLICY CONSIDERATIONS

1550 Use of ozonation at the process level requires an investment in infrastructure but is already used 1551 in many cities throughout the United States in drinking water and wastewater treatment plants 1552 and therefore requires permitting. Use of ozonation has been accepted in these applications for 1553 many decades (Loeb et al. 2012). Ozonation for treatment of active HCB events in surface 1554 waters might be feasible in the future (e.g., via nanobubbles), but at present it remains a research 1555 technique. Excess ozone will naturally convert to oxygen, although at very high concentrations, 1556 ozone can damage fish gills. With ozone monitoring, ecosystem impacts of treated water can be 1557 minimized, likely increasing public acceptance of the method compared to chemical applications 1558 and their residuals.

1559 REFERENCES

1560 Cheng, X., H. Shi, C. D. Adams, T. Timmons, and Y. Ma. 2009. "Effects of oxidative and physical treatments on 1561 inactivation of Cylindrospermopsis raciborskii and removal of cylindrospermopsin." Water Sci Technol 60 1562 (3):689-97. doi: 10.2166/wst.2009.385. 1563 Dore, Mohammaed H., Rajiv G. Singh, Arian Khaleghi-Moghadam, and Gopal Achari. 2013. "Cost differentials and 1564 scale for newer water treatment technologies." International Journal of Water Resources ad environmental 1565 Engineering 5 (2):100-109. doi: https://doi.org/10.5897/IJWREE12.103. 1566 Fawell, JK, J Hart, s HA Jame, and r W Par. 1993. "Blue-green algae and their toxins-analysis, treatment and 1567 environmental control." Water Supply 11 (3/4):109-115. 1568 Ho, L., G. Newcombe, and J. P. Croué. 2002. "Influence of the character of NOM on the ozonation of MIB and 1569 geosmin." Water Res 36 (3):511-8. doi: 10.1016/s0043-1354(01)00253-6. 1570 Loeb, Barry L., Craig M. Thompson, Joseph Drago, Hirofumi Takahara, and Sylvie Baig. 2012. "Worldwide Ozone 1571 Capacity for Treatment of Drinking Water and Wastewater: A Review." Ozone: Science & Engineering 34 1572 (1):64-77. doi: 10.1080/01919512.2012.640251. 1573 Newcombe, Gayle, and B. C. Nicholson. 2004. "Water treatment options for dissolved cyanotoxins." Journal of 1574 Water Supply: Research and Technology - AQUA 53:227-239. doi: 10.2166/aqua.2004.0019. 1575 Onstad, G. D., S. Strauch, J. Meriluoto, G. A. Codd, and U. Von Gunten. 2007. "Selective oxidation of key 1576 functional groups in cyanotoxins during drinking water ozonation." Environ Sci Technol 41 (12):4397-404. 1577 doi: 10.1021/es0625327.

262 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1578 Pandhal, J., A. Siswanto, D. Kuvshinov, W. B. Zimmerman, L. Lawton, and C. Edwards. 2018. "Cell Lysis and 1579 Detoxification of Cyanotoxins Using a Novel Combination of Microbubble Generation and Plasma 1580 Microreactor Technology for Ozonation." Front Microbiol 9:678. doi: 10.3389/fmicb.2018.00678. 1581 Rice, R. G. 1991. "Recent Advances in Ozone Treatment of Drinking Water." In Chemistry for the Protection of the 1582 Environment, edited by L. Pawlowski, W. J. Lacy and J. J. Dlugosz, 713-730. Boston, MA: Springer US. 1583 Rositano, J., G. Newcombe, B. Nicholson, and P. Sztajnbok. 2001. "Ozonation of NOM and algal toxins in four 1584 treated waters." Water Res 35 (1):23-32. doi: 10.1016/s0043-1354(00)00252-9. 1585 Staehelin, Johannes, and Juerg Hoigne. 1985. "Decomposition of ozone in water in the presence of organic solutes 1586 acting as promoters and inhibitors of radical chain reactions." Environmental Science & Technology 19 1587 (12):1206-1213. doi: 10.1021/es00142a012. 1588 Zamyadi, A., L. A. Coral, B. Barbeau, S. Dorner, F. R. Lapolli, and M. Prévost. 2015. "Fate of toxic cyanobacterial 1589 genera from natural bloom events during ozonation." Water Res 73:204-15. doi: 1590 10.1016/j.watres.2015.01.029.

1591

263 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1592 PHOSPHORUS-BINDING COMPOUNDS

1593 In-lake Prevention Strategy Substantial Supporting Field Data

1594 Geoengineering involves the addition of phosphorus-binding (“P-binding”) elements to lake 1595 bottom sediments to bind sediment phosphorus and control the release of phosphorus from 1596 sediment during low oxygen conditions (e.g., internal phosphorus loading control). Minerals 1597 containing aluminum are naturally abundant in the environment, and aluminum content of soils 1598 and sediment is generally between 1 and 10% (Sorenson et al. 1974, USGS 1984). Natural lake 1599 water concentrations of aluminum range from 10 to100 ug/L (Wetzel 2001). Aluminum acts by 1600 converting iron-bound and pore water phosphorus to aluminum-bound phosphorus. Aluminum- 1601 bound phosphorus is stable under low oxygen conditions and a wide pH range and is thus 1602 considered permanently inactivated after treatment. Aluminum is commonly applied as alum, 1603 sodium aluminate, and polyaluminum chloride (alum and sodium aluminate are applied together 1604 as a buffer in low alkalinity waters). The material is typically applied as a liquid (by a treatment 1605 barge) to the lake surface where it forms a floc that then settles to the bottom and is incorporated 1606 into the sediment. In some cases, a solid aluminum salt is applied. It is one of the few strategies 1607 used for internal phosphorus control that has extensive field evidence, and it is the only 1608 geoengineering material that has extensive field evidence of longevity, effectiveness, and safety.

1609 There are several factors that determine the effectiveness and longevity of aluminum treatment. 1610 For example, aluminum treatment will be more effective for lakes with significant internal 1611 phosphorus loading relative to watershed phosphorus loads. A high lake surface to tributary 1612 watershed area ratio increases treatment longevity, as a larger ratio is generally indicative of a 1613 lower flushing rate. An approximate cut off is a 7.2 watershed to lake area ratio (Huser et al. 1614 2016) for factors that may affect treatment longevity). Accurate aluminum dosing also increases 1615 effectiveness and longevity (Huser and Pilgrim 2014, Pilgrim, Huser, and Brezonik 2007). 1616 Longevity and effectiveness are greater for lakes with stable thermocline and infrequent mixing. 1617 However, this does not preclude the use of aluminum for systems that mix, given that 1618 phosphorus transport from the lake bottom is mediated by mixing. Aluminum may be very 1619 effective for systems that mix, but longevity of a treatment is largely determined by new 1620 phosphorus inputs. Shallow systems experience more phosphorus load per unit lake volume 1621 compared to a deep lake, given equal watershed inputs. Although longevity is often reduced for 1622 shallow systems primarily due to continued excess external loading of phosphorus, treatment can 1623 be used effectively for shallow lakes if factors such as benthic feeding fish, invasive aquatic 1624 plants, and best management practices (ponds, wetlands, and filtration for phosphorus removal) 1625 are also implemented (Bartodziej, Blood, and Pilgrim 2017). Trophic state is not a determinant 1626 of use, and aluminum can be used for a wide range of sediment phosphorus concentrations. For 1627 eutrophic systems, application is most often conducted in the spring and fall to avoid algal 1628 blooms or aquatic plants interfering with floc formation and settling. It is also notable that 1629 treatment effectiveness has been recently demonstrated for estuarine waters using polyaluminum 1630 chloride (Rydin et al. 2017).

264 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

EFFECTIVENESS NATURE OF HCB • Water body types: pond, lake/reservoir. • Most planktonic HCB types • Any surface area; high lake surface to • Toxic and non-toxin HCB tributary watershed area ratio increases • HCB that are primarily phosphorus limited longevity • Mid-summer internal phosphorus loading • Any depth; effectiveness in shallow and lake-mixing induced HCB systems depends on other factors (benthic • Prevention strategy feeding fish, invasive aquatic plants) and implementing best management practices • Any trophic state; aluminum can be used for a wide range of sediment phosphorus concentrations when best management practices are also implemented • Any mixing regime • Any water body use; see product label for specifications on water body use • Greater effectiveness for lakes with high internal versus external phosphorus loading • Greater effectiveness and longevity when using aluminum dosing methods based on iron-bound phosphorus concentration in the sediment

1631 1632 Figure 1: Applying phosphorous binding compounds to a lake.

1633 Figure source: Images courtesy of K. Pilgrim, Barr Engineering Company. Used with 1634 permission.

1635 Alternative methods include other phosphorus-binding material additions, e.g., modified 1636 bentonite clay (Robb et al. 2003), lime (Ca(OH)2, CaCO3), and ferric chloride (FeCl3) (Chorus 1637 and Bartram 1999). Note, however, that Triest, Stiers, and Van Onsem (2016) caution the use of 1638 lime, as lime-induced increases in lake pH (>8) selects for cyanobacteria. Implementation of

265 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1639 other strategies in the watershed can reduce incoming phosphorus (see Nutrient Management 1640 [hyperlink section] chapter), thereby making in-lake phosphorus-binding additions more 1641 effective and reducing need for re-application.

ADVANTAGES LIMITATIONS • Experienced application contractors • Effectiveness may be reduced for small available in the US water bodies with large watersheds • Relatively low cost • Large sediment and phosphorus load from • Adverse effects understood and can be the watershed can limit treatment longevity controlled to avoid effects on aquatic life and require re-application • Can reduce phosphorus during critical • Permitting is state-specific; some states are summer months when HCB potential is more accustomed to and accepting of elevated aluminum treatment than others • Unlike iron, aluminum minerals are stable • Application may be impractical for very and not released under anerobic conditions large lakes • During treatment, flocculation is rapid, and • Low alkalinity waters will need to be aluminum floc does not reside for an buffered with the use of buffered aluminum extended period in the water column forms or the use of a base with alum • Water quality criteria have been developed • Phosphorus monitoring through time should by the USEPA (USEPA 2018) and hence follow aluminum additions in order to potential risk levels for aquatic life have identify if/when phosphorus-binding is been quantified saturated and another addition should be considered

266 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1642 COST ANALYSIS CASE STUDY EXAMPLE 1643 Overall, aluminum treatment is generally Concentration (g mobile P/m2*1 cm) 1644 considered to be cost effective compared 1645 to other phosphorus control methods 0.01 0.06 0.11 0.16 0.21 0.26 1646 (Bartodziej, Blood, and Pilgrim 2017). 0

1647 The cost to apply aluminum by 5 1648 commercial applicators is typically quoted 10 Elevated

1649 as “per gallon applied.” The cost per Background 1650 gallon applied is the market cost of the 15

1651 liquid aluminum product delivered to the Dpeth in Sediment (cm) 1652 site plus a mark-up by the contractor to 20 1653 apply the product. The amount of 1654 aluminum needed is often determined by 1655 an aerial dose quoted as grams aluminum Step 1. Identify depth of elevated mobile 1656 per square meter of lake bottom area. This phosphorus in sediment. 1657 aerial dose is determined by the amount of 1658 P in the lake bottom sediment. More P Step 2. Calculate average concentration of 1659 (often called “mobile P”) in the lake mobile phosphorus for sediment with elevated 1660 bottom sediments requires more phosphorus. 1661 aluminum. The initial application is 1662 expensive, but aluminum treatments can Step 3: Identify the aluminum dose necessary to 1663 be expected to last 11 years, resulting in a reduce mobile phosphorus to the desired level. 1664 low average cost per growing season. The This may be reducing mobile phosphorus to the 1665 cost will need to be determined on a site- maximum possible or to background levels 1666 specific basis. Previous estimates from 14 identified by sediment cores. Use the methods of 1667 studies indicate an average cost of Pilgrim, Huser, and Brezonik (2007) to identify 1668 $5275/acre (2020 $US, Appendix 1 the expected mobile phosphorus reduction with 1669 [hyperlink appendix]). alum dose. An example of this relationship is identified below. 1670 Table 1: Phosphorus-binding compounds Estimated Mobile Phopshorus Binding With A Range of 1671 cost analysis for a treatment. Aluminum Doses

0.25 1) ITEM RELATIVE COST -

PER GROWING 0.2 2 x x 2 cm SEASON - 0.15 Material $$ Mobile P Converted Al-P 0.1 Personal Protective $ Remaining Mobile P

Equipment 0.05 Mobile m (g Mobile P Equipment $$$ 0 Machinery $$ 0 50 100 150 Ratio: Al to Al-P Formed Tools $ Labor $$ O&M Costs $ TOTAL $-$$ 267 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1672

1673 REGULATORY AND POLICY CASE STUDY EXAMPLE 1674 CONSIDERATIONS CONTINUED… 1675 It can be expected that there will be a large 1676 range of comfort with this prevention Step 4: Identify the depth of sediment to be 1677 approach, and each state will have a treated and calculate the total alum dose to 1678 different policy applicable to aluminum applied to the lake as grams aluminum per 1679 treatment. The approval process may not be square meter of lake bottom sediment. 1680 straightforward as aluminum treatment Aluminum Dosing Using Mobile Phosphorus 1681 does not fall under the jurisdiction of most in Sediment and the Methods Pilgrim, Huser, 1682 established permitting programs. It will be and Brezonik (2007), Huser and Pilgrim 1683 necessary to contact the State limnologist (2014). 1684 or appropriate permitting staff.

1685 The primary regulatory hurdle with the application of aluminum for internal load control is the 1686 potential for aluminum-induced short-term (acute) aquatic toxicity during application. Long-term 1687 effects (chronic toxicity) have not been observed for typically applied doses (Clearwater, Hickey, 1688 and Thompson 2014). The literature regarding aluminum aquatic toxicity is extensive and largely 1689 resulting from acid rain research in the 1970s and 1980s (see the USEPA aluminum criteria 1690 development documents for an extensive review on aluminum toxicity). However, the conditions 1691 in eutrophic lakes are very different compared to acidified lakes, considering the predominant 1692 condition where aluminum is acutely toxic (e.g., pH<5.5). The pH range typically found in 1693 eutrophic lakes is most often in the neutral range (pH 79), and there is a large body of evidence 1694 demonstrating safe application of aluminum for the purpose of phosphorus treatment even in low 1695 alkalinity waters. Numerous studies have shown that aluminum treatments had no adverse effect 1696 on aquatic life, and in some cases fish or benthic invertebrate abundances increased (Buergel and 1697 Soltero 1983, Glilman 2006, Narf 1985, Narf 1990, Smeltzer 1990). In contrast to acidification- 1698 related aluminum studies, water column aluminum concentrations have been shown to decrease 1699 in the water after the floc has settled to the sediment (K. Pilgrim and B. Huser, unpublished data 1700 from Minnesota and Sweden). This is due to reduction of particulate matter in the water (i.e. 1701 algae) that can bind with natural aluminum entering the water body. The increasingly common 1702 use of buffered alum and sodium aluminate treatment has improved the ability to regulate pH 1703 during treatment, and application during spring and fall has avoided potential complications with 1704 phytoplankton and cyanobacterial blooms.

1705 REFERENCES

1706 Bartodziej, W. M., S. L. Blood, and Keith Pilgrim. 2017. "Aquatic plant harvesting: An economical phosphorus 1707 removal tool in an urban shallow lake." 55:26-34. 1708 Buergel, Pamela M., and Raymond A. Soltero. 1983. "The Distribution and Accumulation of Aluminum in Rainbow 1709 Trout Following a Whole-Lake Alum Treatment." Journal of Freshwater Ecology 2 (1):37-44. doi: 1710 10.1080/02705060.1983.9664574. 1711 Chorus, Ingrid, and Jamie Bartram. 1999. Toxic cyanobacteria in water : a guide to their public health consequences, 1712 monitoring and management / edited by Ingrid Chorus and Jamie Bertram. Geneva: World Health 1713 Organization.

268 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1714 Clearwater, Susan, Christopher Hickey, and Karen Thompson. 2014. "The effect of chronic exposure to phosphorus- 1715 inactivation agents on freshwater biota." Hydrobiologia 728. doi: 10.1007/s10750-014-1805-9. 1716 Glilman, Bruce. 2006. Pre- and Post-Alum Treatment Survey of Honeoye Lake Macrobenthos: Comprehensive 1717 Field Inventory and Data Summary July 2005 and November 2006. Department of Environmental 1718 Conservation and Horticulture, Finger Lakes Community College. 1719 Huser, B. J., S. Egemose, H. Harper, M. Hupfer, H. Jensen, K. M. Pilgrim, K. Reitzel, E. Rydin, and M. Futter. 1720 2016. "Longevity and effectiveness of aluminum addition to reduce sediment phosphorus release and 1721 restore lake water quality." Water Res 97:122-32. doi: 10.1016/j.watres.2015.06.051. 1722 Huser, B. J., and K. M. Pilgrim. 2014. "A simple model for predicting aluminum bound phosphorus formation and 1723 internal loading reduction in lakes after aluminum addition to lake sediment." Water Res 53:378-85. doi: 1724 10.1016/j.watres.2014.01.062. 1725 Narf, R. P. 1985. Impact of Phosphorus Reduction via Metalimnetic Alum Injection in Bullhead Lake, Wisconsin. 1726 edited by Wisconsin Department of Natural Resources. Madison, WI. 1727 Narf, Richard P. 1990. "Interactions of Chironomidae and Chaoboridae (Diptera) with Aluminum Sulfate Treated 1728 Lake Sediments." Lake and Reservoir Management 6 (1):33-42. doi: 10.1080/07438149009354693. 1729 Pilgrim, K. M., B. J. Huser, and P. L. Brezonik. 2007. "A method for comparative evaluation of whole-lake and 1730 inflow alum treatment." Water Res 41 (6):1215-24. doi: 10.1016/j.watres.2006.12.025. 1731 Robb, Malcolm, Bruce Greenop, Zoë Goss, Grant Douglas, and John Adeney. 2003. "Application of Phoslock™, an 1732 Innovative Phosphorus Binding Clay, to Two Western Australian Waterways: Preliminary Findings." 1733 Hydrobiologia 494. doi: 10.1023/A:1025478618611. 1734 Rydin, E., L. Kumblad, F. Wulff, and P. Larsson. 2017. "Remediation of a Eutrophic Bay in the Baltic Sea." 1735 Environ Sci Technol 51 (8):4559-4566. doi: 10.1021/acs.est.6b06187. 1736 Smeltzer, Eric. 1990. "A Successful Alum/Aluminate Treatment of Lake Morey, Vermont." Lake and Reservoir 1737 Management 6 (1):9-19. doi: 10.1080/07438149009354691. 1738 Sorenson, J. R., I. R. Campbell, L. B. Tepper, and R. D. Lingg. 1974. "Aluminum in the environment and human 1739 health." Environ Health Perspect 8:3-95. doi: 10.1289/ehp.7483. 1740 Triest, Ludwig, Iris Stiers, and Stijn Van Onsem. 2016. "Biomanipulation as a nature-based solution to reduce 1741 cyanobacterial blooms." Aquatic Ecology 50 (3):461-483. doi: 10.1007/s10452-015-9548-x. 1742 USEPA. 2018. Final Aquatic Life Ambient Water Quality Criteria for Aluminum 2018 EPA 822-R-18-001. 1743 Washington, D. C.: U. S. Environmental Protection Agency, Office of Water. 1744 USGS. 1984. Element Concentrations in Soils and Other Surficial Materials of the Conterminous United States, 1745 Geological Survey Professional Paper 1270. edited by U. S. Geological Survey. Alexandria, VA: U. S. 1746 Geological Survey. 1747 Wetzel, Robert G. . 2001. Limnology: Lake and River Ecosystems. San Diego, CA: Academic Press.

1748

269 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1749 PERMANGANATE

1750 In-lake Intervention Strategy Limited Supporting Field Data

1751 Permanganate is an oxidizing agent that has been used as an algaecide for in-lake treatment of 1752 HCBs and excessive algae levels, as well as mitigating cyanotoxins, in a limited number of 1753 documented cases during the past century. Permanganate may be applied by spraying water 1754 surfaces or by feeding solid or slurry forms from a watercraft. This strategy can be effective at 1755 both physically removing or damaging cyanobacterial cells and destroying cyanotoxins. 1756 Permanganate, when used as an open-water algaecide, is typically applied as a potassium 1757 permanganate product.

EFFECTIVENESS NATURE OF HCB • Water body type: ponds, lake/reservoir • Microcystin- or anatoxin-a forming HCB • Surface area: small • Singular or repeating bloom • Depth: shallow • Toxic and non-toxic HCH; high doses may lyse cells and release cyanotoxin • Targets all algal species • Intervention strategy

1758 Potassium permanganate (KMnO4) has been applied to water bodies in limited full-scale studies, 1759 primarily at reservoirs, since the 1960s (Ficek 1983). Application goals have varied, due to its 1760 ability to react with organic compounds such as algal/cyanobacterial cells, cyanotoxins, bacteria, 1761 fish, dissolved and particulate organic matter, and metals such as iron. As an algaecide, 1762 potassium permanganate affects cyanobacteria cell integrity, cyanotoxin release, and oxidation 1763 (Fan et al. 2013). In drinking water facilities, low doses of permanganate (1 and 3 mg/L) and 1764 short contact time may be most effective at reducing intracellular and extracellular cyanotoxins 1765 without lysing cyanobacterial cells, while also reducing soluble manganese and iron (Fan et al. 1766 2013). However, bench studies by USEPA have presented evidence that 3 mg/L of permanganate 1767 may increase cell lysis and consequently extracellular microcystins compared to 1.2 mg/L. The 1768 bench studies were used in tandem with coagulation to test efficiency of coagulation with 1769 permanganate treatment as its application in treatment facilities can lower coagulant dose 1770 requirements and improve clarification during treatment process for drinking water. Higher doses 1771 (5 mg/L) were most effective at degrading extracellular microcystins more quickly than lower 1772 doses. Therefore, the use of permanganate and its effectiveness is dependent upon dose, contact 1773 time, pH, and temperature. Care must be taken to use proper doses to avoid excessive 1774 intracellular cyanotoxin release and to avoid potential toxic effects on aquatic life. While limited 1775 field use has been documented, early applications (before summer increases in surface water 1776 temperatures) have been shown to be effective (Ficek 1983).

1777

270 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

ADVANTAGES LIMITATIONS • Intervention and possible prevention • Limited documented application as an strategy intervention technique for HCBs, and most • Improves clarity through sedimentation studies are based on drinking water • Iron and manganese reduced in water treatment process • Algicidal rather than algistatic • Needs infrastructure (boat and/or sprayer) • Limited cell lysis at lower tested doses • After cell lysis, cyanotoxins can be released • Can also destroy some cyanotoxins and could pose problems for drinking water • Thorough documentation for use in facilities and recreational activities treatment in drinking water facilities for • Low oxygen levels may require aeration non-HCB uses • Fish toxicity • Indiscriminate on all algal species • Purple or pink color during application • Effectiveness may be surface water temperature dependent 1778 COST ANALYSIS CASE STUDY EXAMPLE 1779 The cost of a treatment is dependent on the 1780 Pond, Wellesley, Massachusetts, United area treated, depth of water body, labor, States: Potassium permanganate was applied 1781 product used, chemical characteristics of the at an average dose of 1.4 mg/L KMnO4 to a 1782 water body, and algal/cyanobacterial bloom 1783 112-acre pond in Wellesley, Massachusetts in severity, as well as other mitigating factors 1974, following seven years of copper sulfate 1784 (such as chemical supply, local permit fees, 1785 use for algae control. Copper sulfate had etc.). become ineffective in controlling the cyanobacteria, identified as Anabaena and 1786 Common reported application doses are Aphanizomenon. 1787 approximately 2 mg/L but will vary 1788 depending on organic load in the water. For In this case, potassium permanganate was 1789 water bodies smaller than one-acre, 1790 applied before the water temperature reached crystalline (or powder) potassium 68 degrees F, prior to initial Anabaena 1791 permanganate may be added to the water by 1792 blooms. In 1975, reduced cell counts of spraying the solution over the water while on Anabaena and Aphanizomenon were 84 and 1793 foot. Larger water bodies require a motorized 1794 99%, respectively. Applications were repeated watercraft from which the chemical can be in 1976 through 1979. 1795 applied with a submersible pump or gravity 1796 feed from a large tank. More information on this case study can be found in Carr (1979). 1797 Personal protective equipment including eye, 1798 skin, and inhalation protection is required. 1799 Rubber glove, goggles, and dust masks are 1800 necessary.

1801

271 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1802 Table 1: Permanganate cost analysis per growing season.

ITEM RELATIVE COST PER GROWING SEASON Material $$ Personal Protective $$ Equipment Equipment $$ Labor $ O&M Costs $ OVERALL $$

1803 REGULATORY AND POLICY CONSIDERATIONS

1804 Policies and regulations differ by state, and often regionally within states. Regardless, 1805 application permits are required in most places, and applications are often limited to products on 1806 approved pesticide lists. Registered/licensed pesticide professionals are often required to apply 1807 the product. In addition, treatments may be restricted in certain water bodies by state policy, 1808 along with the size and frequency of the treatments. Water body use restrictions are presented on 1809 the products’ material safety datasheets, but additional restrictions may be required in some 1810 jurisdictions.

1811 Permanganate is a strong oxidant used primarily as a pre-treatment process at the raw water 1812 intake of drinking water sources. Its application is to reduce manganese and iron by forming 1813 solid ferric hydroxide (FeOH3) and solid manganese dioxide (MnO2), which can then be 1814 removed by filtration. Potassium permanganate is also often added in the water treatment process 1815 to control taste and odors, remove color, and control biological growth, such as zebra mussels in 1816 pipelines. Its application has also been common in small aquaculture operations to also control 1817 parasites and viruses. There are limited studies of use in lakes and reservoirs and its use as an 1818 algaecide must be carefully considered since it can promote an increase in extracellular 1819 cyanotoxins.

1820 Permanganate in any form is a manganese compound. Any application of this chemical to a 1821 water body will introduce manganese to the water column and sediment, and therefore, to any 1822 potable uses of the water body. The USEPA Drinking Water Health Advisory for Manganese 1823 (USEPA 2004) recommends reducing drinking-water manganese concentrations to or below 1824 0.050 mg/L, the Safe Drinking Water Act secondary maximum contaminant level (SMCL). The 1825 USEPA has also issued a lifetime health advisory value of 0.3 mg/L to protect against potential 1826 neurological effects. Children and adults who drink water with high levels of manganese for a 1827 long period of time may have problems with memory, attention, and motor skills. Infants (babies 1828 under one year of age) may develop learning and behavioral problems if they drink water with 1829 too much manganese. Public water systems may test their water for manganese, but they are not 1830 required to do so.

1831 272 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1832 REFERENCES

1833 Carr, J. B. 1979. Retarding Blue-Green Algal Blooms in Water Bodies - from Integrated Iron and Nitrogen Control 1834 for lake Restoration In U. S. Environmental Protection Agency Clear Lakes Program 314(a). 1835 Fan, J., R. Daly, P. Hobson, L. Ho, and J. Brookes. 2013. "Impact of potassium permanganate on cyanobacterial cell 1836 integrity and toxin release and degradation." Chemosphere 92 (5):529-34. doi: 1837 10.1016/j.chemosphere.2013.03.022. 1838 Ficek, Kenneth J. . 1983. "Raw Water Reservoir Treatement with Potassium Permanganate " 74th Annual Meeting, 1839 Ilinois Section of the American Water Works Association, Chicago, IL. 1840 USEPA. 2004. Drinking Water Health Advisory for Manganese EPA 822-R-04-003. Washington, D. C.: U. S. 1841 Environmental Protection Agency, Office of Water.

1842

1843 .

273 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1844 PEROXIDE APPLICATION

1845 In-lake Intervention Strategy Substantial Supporting Field Data

1846 Substantial field evidence indicates that applying a crystalized peroxide compound or a liquid 1847 peroxide mixture (Mattheiss, Sellner, and Ferrier 2017, Matthijs et al. 2012) to a non-flowing 1848 water body can rapidly reduce HCBs as well as cyanotoxins. The crystal can be deployed in 1849 several hours to a day and sinks to the bottom so can be used for planktonic cyanobacteria as 1850 well as near-bottom or bottom populations. Field evidence from the Netherlands indicates that a 1851 lake water-diluted peroxide solution can be effective in HCB control, via dispersal at multiple 1852 depths (Matthijs et al. 2012). Effective peroxide concentrations appear to be 2.3 mg/L for 1853 Planktothrix agardhii, 3-4 mg/L for Aphanizomenon and Anabaena/Dolichospermum, and >5 1854 mg/L for M. aeruginosa (this taxon may require more than 5 mg/L, but zooplankton mortalities 1855 can occur much beyond 5 mg/L) (Matthijs et al. 2016, Zhou et al. 2018).

EFFECTIVENESS NATURE OF HCB • Water body types: pond, lake/reservoir; • All HCB types; planktonic, near-bottom, any non-flowing freshwater system and bottom cyanobacteria • Surface area: small • Singular or repeating bloom Depth: shallow • Toxic or non-toxic HCBs • All trophic states • Effective for most cyanobacteria • All mixing regimes • Intervention strategy • All water body uses 1856

ADVANTAGES LIMITATIONS • Rapidly decomposes to O2 and H2O • Requires access to surface area, e.g., boat • Oxidizes cyanobacterial cells and • Peroxide compounds need special handling cyanotoxins and possible state required training and • Effective at <5 mg/L application permit • Modest cost/acre with dose dependent on • Can release toxins from cells (but peroxides cyanobacterial biomass can quickly oxidize these compounds) • Field use common • At H2O2 >5 mg/L, may impact zooplankton and fish • May be less effective in highly turbid systems

274 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1857 1858 Figure 1: Granular and liquid peroxide application (

1859 Figure Source: J. Mattheiss, Hood CCWS and Matthijs et al. 2012, Used with permission.

1860 COST ANALYSIS

1861 Costs for granule application are modest to CASE STUDY EXAMPLES 1862 moderate and used most often on ponds and 1863 small lakes, depending on amount of the Lake Anita Louise, Frederick County, 1864 HCB and water body size. Liquid dosing is Maryland, United States: Mattheiss, Sellner, 1865 much more expensive. Dosing and hence and Ferrier (2017) reported that 350 lb. of 1866 cost/acre is listed on each product but peroxide crystals were dispersed over ~4.5 1867 seeking <5 mg/L in-lake H2O2 should be acres, 10-12 ft deep system from a small boat in 1868 the goal. Granular peroxide compounds are approximately 3 h. Peroxide concentrations 1869 not inexpensive but cost is modest relative approximated 3 mg/L and rapidly declined to 1870 to mechanical strategies. However, 1-2 background levels in 3 d. Densities of a P. 1871 treatments per year or over several years agardhii surface bloom were dramatically 1872 may be required. Small boats and 2 persons reduced and remain low 4 years after treatment. 1873 can disperse granular compounds, but 1874 special liquid dispensing equipment Various locations: Liquid application with 1875 (additional cost) may be needed for peroxide levels at ~3 mg/L have also proved 1876 multiple depth injection. See Appendix 1 effective in Lake Koetshuis (Matthijs et al. 1877 [hyperlink appendix] for other estimates. 2012) and Ouwerkerkse Kreek, Netherlands (Burson et al. 2014) and an Alabama 1878 aquaculture pond (Yang et al. 2018).

275 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1879 Table 1: Peroxide cost analysis per growing season.

ITEM RELATIVE COST PER GROWING SEASON Material $-$$ Personal Protective $ Equipment Equipment $-$$$ Labor $-$$ TOTAL $$

1880 REGULATORY AND POLICY CONSIDERATIONS

1881 Training of an applicator and permits for application may be required in many states. Check 1882 individual state regulations.

1883 REFERENCES

1884 Mattheiss, J, K. G. Sellner, and D. Ferrier. 2017. Lake Anita Louise Peroxide Treatment Summary. In CCWS 1885 Contribution Frederick, MD: Center for Coastal and Watershed Studies, Hood College. 1886 Matthijs, H. C., P. M. Visser, B. Reeze, J. Meeuse, P. C. Slot, G. Wijn, R. Talens, and J. Huisman. 2012. "Selective 1887 suppression of harmful cyanobacteria in an entire lake with hydrogen peroxide." Water Res 46 (5):1460- 1888 72. doi: 10.1016/j.watres.2011.11.016. 1889 Matthijs, Hans C. P., Daniel Jančula, Petra M. Visser, and Blahoslav Maršálek. 2016. "Existing and emerging 1890 cyanocidal compounds: new perspectives for cyanobacterial bloom mitigation." Aquatic Ecology 50 1891 (3):443-460. doi: 10.1007/s10452-016-9577-0. 1892 Yang, Zhen, Riley P. Buley, Edna G. Fernandez-Figueroa, Mario U. G. Barros, Soorya Rajendran, and Alan E. 1893 Wilson. 2018. "Hydrogen peroxide treatment promotes chlorophytes over toxic cyanobacteria in a hyper- 1894 eutrophic aquaculture pond." Environmental Pollution 240:590-598. doi: 1895 https://doi.org/10.1016/j.envpol.2018.05.012. 1896 Zhou, Q., L. Li, L. Huang, L. Guo, and L. Song. 2018. "Combining hydrogen peroxide addition with sunlight 1897 regulation to control algal blooms." Environ Sci Pollut Res Int 25 (3):2239-2247. doi: 10.1007/s11356- 1898 017-0659-x.

1899

1900 .

276 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1901 SHADING WITH DYES (LIGHT FILTERING)

1902 In-lake Intervention Strategy Limited Supporting Field Data

1903 Dyes may be added to ponds and small lakes to physically filter sunlight with the goal of 1904 reducing photosynthesis and cyanobacteria growth. A commercial dye product ais added to the 1905 shoreline of ponds or small lakes beginning in spring and periodically during the “growing 1906 season” to reduce the potential for and severity of HCBs. These non-toxic dyes naturally disperse 1907 and can filter out certain light spectra and reduce light penetration to “shade” the water body. 1908 Dyes are available in blue, black and other colors. Testing suggests that dyes are likely to be 1909 most effective on aquatic plants, algae and cyanobacteria which are at least 2 feet below the 1910 surface (NYSFOLA 2009). Commercial dyes for this application have been available in the 1911 marketplace for decades but there is limited published scientific demonstration of effectiveness.

1912 Application rates will vary by dye manufacturer, but dosing rates of commonly used dyes are in 1913 the range of 1 to 2 gallons of dye solution per million gallons of water (Madsen et al. 1999). 1914 After initial dye dosing, periodic re-dose is necessary in order to maintain the shade color and 1915 light filtering properties to counter dye fading and dilution from inflowing water (Ludwig, 1916 Perschbacher, and Edziyie 2010).

1917 If the pond or small lake is deeper than 2 feet and has had a history of repeated cyanobacterial 1918 blooms, the dye light filtering/shading approach may be a prevention technology for you to 1919 consider either alone or in conjunction with other technologies. Method practicality and costs 1920 largely hinge on the volume of the water body and the dilution caused by clear water inflows 1921 from streams, springs, etc; the larger the volume and dilution, the more dye you will need to add. 1922 While eutrophic waters are the most likely candidates for the approach, there are no established 1923 specific trophic state or mixing regime requirements. Using dye shading to limit photosynthesis 1924 may affect growth of some cyanobacterial species more than others depending on light 1925 sensitivity and where they reside relative to the water surface. As a result, you may change the 1926 species of algae and cyanobacteria which predominate (NYSFOLA 2009, Suski et al. 2018).

EFFECTIVENESS NATURE OF HCB • Water body types: pond, lake/reservoir • Sub-surface HCB • Any depth • Toxic and non-toxic HCBs • Trophic state: eutrophic • Prevention strategy • Any mixing regime • Water body uses: recreation, drinking water 1927

277 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

ADVANTAGES LIMITATIONS • Unlikely carry-over after bloom • Cost effective only for small lakes and those dissipation with long residence time • Low potential for adverse impacts • Inhibits photosynthesis of all algae not just • Available and relatively inexpensive cyanobacteria • Minimal technical expertise, manpower, • Can interfere with pigment analyses used to electricity, or specialized equipment characterize blooms (Buglewicz and needed Hergenrader 1977) • Shading dyes appear to be nontoxic • May alter lake ecology, changing dominant (USEPA 2005, WSDE 2016) plant, algae, and fish species (NYSFOLA 2009, Suski et al. 2018) • Limited proof of effectiveness, and blooms may return • Typically proprietary blends of non-toxic dyes (WSDE 2016) - most shading products are not labeled as registered pesticides and full chemical composition may not be given with product. • Permit may be required

1928 1929 Figure 1: Left: Dyofix, Town End (Leeds) PLC, United Kingdom, 2019 (used with permission). 1930 Right: HCB in dyed pool (provided and used with permission from J. B. Hyde).

1931 The aquatic growth control technology dates back at least 72 years (Eicher 1947), and 1932 commercial dye products for this purpose have been available for at least 40 years. Researchers 1933 have found at least one shading dye does not significantly reduce the visibility in water for 1934 swimmers and other recreators (Madsen et al. 1999). Dyes may be used in conjunction with other 1935 cyanobacteria preventative or control technologies. Perhaps most importantly, you might find 1936 that dyes may have little to no effect on reducing cyanobacteria bloom frequency or severity.

278 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1937 Some laboratory experiments and field-scale pilot CASE STUDY EXAMPLE 1938 studies conducted in 2- to 3-foot water depths 1939 showed that prescribed concentrations of a leading Teton Pond, Dunbar, Nebraska, United States: 1940 pond dye had little to no effect on algal growth Buglewicz and Hergenrader (1977) performed 1941 rates or phytoplankton communities (Boyd, a field-scale pilot study on a 2.4-acre pond 1942 Hanapi, and Noor 1982, Ludwig, Perschbacher, and west of Dunbar, Nebraska, ~5.2 feet deep, and 1943 Edziyie 2010, Spencer 1984). fed by a 147-acre watershed of fertilized farmland during the April – September 1944 COST ANALYSIS growing season. Six isolation test box enclosures were 1945 Low seasonal cost for pond or small lake with 1946 constructed within the pond. No dye was added limited flow through. to one box, serving as the test control, and no dye was added to the pond outside of the 1947 Table 1: Shading with dyes cost analysis per enclosures. 1948 growing season. Alizanine blue dye was added to 3 enclosures ITEM RELATIVE COST at 3 different concentrations that reduced PER GROWING Secchi disc visibility from 10 feet to just 12, 6 SEASON and 4 inches, respectively. Secchi depths Material $ eventually stabilized to 12 inches in all blue- Equipment $ dyed boxes. Labor $ Sandolan dark brown dye was added to 2 TOTAL $ enclosures at 2 different concentrations that reduced Secchi disc visibility from 10 feet to 1949 REGULATORY AND POLICY 24 and 12 inches, respectively. Secchi depths 1950 CONSIDERATIONS eventually stabilized to 18 inches in all brown- dyed boxes. 1951 Commercially available non-toxic dyes are suitable Cyanobacteria were eliminated from both 1952 for uses in waters used for swimming and other Sandolan brown-dyed boxes and from 1 of the 1953 recreational purposes; however, there may be 3 enclosures dyed with Alizanine blue. 1954 regulatory obstacles or prohibitions against use in Cyanobacteria algal volumetric share increased 1955 drinking water reservoirs. A permit from the state substantially in treated this box even though 1956 herbicide/pesticide control agency may be required the cyanobacteria share remained steady in 1957 prior to use. Also, if the water body is a public untreated control boxes. 1958 water supply source, there may be federal, state, or 1959 local restrictions against use of shading dyes so Cyanobacteria treatment effectiveness results 1960 check with the environmental regulatory agency were mixed despite reducing light penetration. 1961 before moving ahead (NYSFOLA 2009). It is possible the test may not have fairly evaluated dyes as a preventative technology 1962 The dyes will impart a new and unnatural color to since cyanobacteria were already a sizable 1963 the water that may not be appealing to some. fraction of the total algal volume before the test 1964 Furthermore, the public may view the technique as was initiated. 1965 adding a man-made “chemical” to the environment 1966 in order to engineer the disruption of a naturally 1967 occurring, albeit undesirable, cyanobacteria bloom aquatic phenomenon (NYSFOLA 2009).

279 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1968 Before applying dyes to community waters, solicit input from the stakeholders to ensure there is 1969 public consensus for intervention.

1970 REFERENCES

1971 Boyd, Claude E., Md Hanapi, and Md Noor. 1982. "Aquashade(R) Treatment of Channel Catfish Ponds." North 1972 American Journal of Fisheries Management 2 (2):193-196. doi: 10.1577/1548- 1973 8659(1982)2<193:atoccp>2.0.co;2. 1974 Buglewicz, Eugene G., and Gary L. Hergenrader. 1977. "The Impact Of Artificial Reduction Of Light On A 1975 Eutrophic Farm Pond." Transactions of the Nebraska Academy of Sciences and Affiliated Societies 4. 1976 Eicher, George. 1947. "Aniline Dye in Aquatic Weed Control." The Journal of Wildlife Management 11 (3):193- 1977 197. doi: 10.2307/3796277. 1978 Ludwig, Gerald M., Peter Perschbacher, and Regina Edziyie. 2010. "The Effect of the Dye Aquashade® on Water 1979 Quality, Phytoplankton, Zooplankton, and Sunshine Bass, Morone chrysops×M. saxatilis, Fingerling 1980 Production in Fertilized Culture Ponds." Journal of the World Aquaculture Society 41 (s1):40-48. doi: 1981 10.1111/j.1749-7345.2009.00331.x. 1982 Madsen, John D., Kurt D. Getsinger, R. Michael Stewart, John G. Skogerboe, David R. Honnell, and Chetta S. 1983 Owens. 1999. "Evaluation of Transparency and Light Attenuation by Aquashade™." Lake and Reservoir 1984 Management 15 (2):142-147. doi: 10.1080/07438149909353958. 1985 NYSFOLA, (New York State Federation of Lake Associations). 2009. Diet for a Small Lake: The Expanded Guide 1986 to New York State Lake and Watershed Management: New York State Federation of Lake Associations, 1987 Inc. . 1988 Spencer, David F. 1984. "Influence of Aquashade on Growth, Photosynthesis, and Phosphorus Uptake of 1989 Microalgae." Journal of Aquatic Plant Management 22:80-84. 1990 Suski, J. G., C. M. Swan, C. J. Salice, and C. F. Wahl. 2018. "Effects of pond management on biodiversity patterns 1991 and community structure of zooplankton in urban environments." Sci Total Environ 619-620:1441-1450. 1992 doi: 10.1016/j.scitotenv.2017.11.153. 1993 USEPA. 2005. Waste from the Production of Dyes and Pigments Listed as Hazardous EPA 530-F-05-004. 1994 Washington, D. C. : U. S. Environmental Protection Agency. 1995 WSDE. 2016. Aquatic Plant and Algae Management General Permit Fact Sheet – 2016 Olympia, WA: Washington 1996 State Department of Ecology.

1997

1998 .

280 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

1999 SKIMMING AND HARVESTING

2000 In-lake Prevention Strategy Limited Supporting Field Data

2001 There is little available detail on the technologies for skimming or harvesting cyanobacteria from 2002 natural systems. A large surfactant, flotation, skimming, ozonation technology has been used in a 2003 pilot project in Florida (Page et al. 2020) that shows promise for removal of cyanobacteria and 2004 possible toxin destruction. A second is a skimming application in Southampton, NY 2005 (Southampton Press 2019). Although harvesters for submersed aquatic plants are known and 2006 used occasionally for removal of invasive submersed grasses, such as Hydrilla (McGehee 1979), 2007 data that support the removal of cyanobacteria biomass from concentrated blooms with these 2008 techniques are limited.

EFFECTIVENESS NATURE OF HCB • Water body types: pond, lake/reservoir, • Scum-forming or floating HCBs bay/estuary; systems allowing scum • Singular or repeating HCB formation • Toxic and non-toxic HCB • Any depth • Intervention strategy • Any surface area • Water body uses: Any except perhaps drinking water sources • Any trophic state • Any mixing regime • Reported (no data) treatment of 100M gal/d

2009 The sole estimate found for efficacy of harvesting and skimming is in the 2019 Florida pilot 2010 project (Page et al. 2020). Unfortunately, much of the cyanobacteria present were sub-surface, 2011 and there was little cyanotoxin (microcystin) detected. The majority of the results were for 2012 nutrient removal, quite effective for both nitrogen and phosphorus that is mostly found in the 2013 cyanobacteria biomass. There were two major limitations for the technology, however: huge 2014 capital and operations and management costs as well as very high energy demand. Page et al. 2015 (Page et al. 2020) argue that these costs could be reduced if the harvested biomass could then be 2016 converted to biofuels and sold, but that technology is still in development.

2017 As both skimming and flotation cannot remove all of a bloom, the remaining populations could 2018 ‘re-seed’ additional blooms. For skimmed cyanobacteria without biofuel conversion, the 2019 collected material could be considered hazardous waste with associated costs for its disposal. 2020 Subsequent disposal of collected biomass may be limited depending on cyanotoxin content of the 2021 collected biomass.

2022

281 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

ADVANTAGES LIMITATIONS • Biofuel production from harvested • Limited data biomass is proposed • Huge capital investment for reagents, air • Low potential for adverse impacts flotation technology, ozone, and O&M • High volumes of surface scum biomass • Scalable can be harvested • Hazardous waste designation for collected biomass possible • Indiscriminate removal • Scum is collected so there may be surface water criteria concerns • Unknown costs • Need partners for post-collection commercial use 2023 COST ANALYSIS CASE STUDY EXAMPLES 2024 Costs are relatively low for simple skimming and 2025 Lake Okochobee and Newnans Lake, very high for surfactant-air flotation-skimming- Florida, United States: Skimming alone, 2026 ozone treatment. Specific equipment for skimming 2027 or flotation followed by skimming, are or harvesting would be required, and some form of two strategies offered as intervention 2028 power would be needed. The relative costs below 2029 technologies for HCB removal in New are for skimming only and surfactant-flotation- York and Florida, respectively. In 2030 skimming-ozonation. If harvested biomass can be 2031 Florida (Page et al. 2020), a pilot study processed for commercial uses, net overall cost of the surfactant-air flotation-skimming- 2032 may be reduced. Whether funds recovered from 2033 ozone technology was conducted in Lake the sale of the collected material are passed on to Okochobee and Newnans Lake. 2034 the lake manager to reduce their costs is unknown. 2035 Unfortunately for estimates of efficacy, little scum cyanobacteria were present; 2036 Table 1: Skimming and harvesting cost analysis most biomass was at depth, and low 2037 per growing season. toxin concentrations (<1 ppb). Results indicated that most of the nitrogen and ITEM RELATIVE COST PER phosphorus was found in the cells, and GROWING SEASON removal of nutrients was very high. The Material $$-$$$ technology shows promise, particularly Personal Protective $$ when surface cyanobacteria densities are Equipment elevated, but the treatment costs are very Equipment $$-$$$ high, estimated from $2M-$18M/year. Machinery $$-$$$ Southampton, New York, United States: Tools $-$$$ Detail on the pilot program in New York Labor $$-$$$ can be found in The Southampton Press O&M Costs $-$$$ (2019). Disposal $$$ OVERALL $$-$$$

282 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

2038 REGULATORY AND POLICY CONSIDERATIONS

2039 Collected biomass may include intracellular cyanotoxins, so appropriate use of the harvested 2040 biomass will depend on cyanotoxin concentration of the material. If non-toxic, landfill 2041 application or use as wet “fertilizer” might be possible; composting would likely be allowed, but 2042 authorities would need to be contacted for local regulations. If processors can be found for use in 2043 the synthesis of commercial products such as foam rubber or biofuels, disposal permitting may 2044 not be necessary. If cyanotoxins are present, then permits for use of the collected biomass would 2045 be needed, and local-to-state officials should be contacted. For both toxic and non-toxic biomass, 2046 harvesting would remove cellular nitrogen and phosphorus, assisting in nutrient removal from 2047 impacted water bodies and therefore possible “credit” for TMDLs in a watershed

2048 REFERENCES

2049 McGehee, J. T. 1979. "Mechanical hydrilla control in Orange Lake, Florida." J. Aquat. Plant Manage. 17:58-61. 2050 Page, Martin A., Bruce A. MacAllister, Angela. Urban, Christopher L. Veinotte, Irene E. MacAllister, Kaytee L. 2051 Pokrzywinski, Jim. Riley, Edith Martinez-Guerra, 1989-, Craig S. White, Chris. Grasso, Alan James 2052 Kennedy, 1976-, Catherine C. Thomas, Justin. Billing, Andrew Schmidt, Dan. Levy, Bill. Colona, David. 2053 Pinelli, and Chandy. John. 2020. Harmful Algal Bloom Interception, Treatment, and Transformation 2054 System, "HABITATS". edited by U. S. Army Corps or Engineers. Champaign, IL: U. S. Army Corps or 2055 Engineers. Construction Engineering Research Laboratory. 2056 Southampton Press. 2019. "Governor Cuomo And DEC Launch Blue-Green Algae Removal Pilot Program In 2057 Southampton Village." The Southampton Press, 10/3/2019, Environment/Neighborhood. 2058 https://www.27east.com/southampton-press/governor-cuomo-and-dec-launch-blue-green-algae-removal- 2059 pilot-program-in-southampton-village-1540878/.

2060

283 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

2061 ULTRASOUND

2062 In-lake Prevention Strategy Limited/Emerging Supporting Field Data

2063 Many species of cyanobacteria can regulate their buoyancy in the water column through special 2064 internal structures known as gas vesicles (Reynolds and Walsby 1975, Walsby et al. 1997)). 2065 These provide a competitive advantage over other phytoplankton. Cells with gas vesicles 2066 accumulate at the surface during the day to use available light for photosynthesis, shading out 2067 competing non-cyanobacterial species. Late in the day, accumulated sugars/carbohydrates from 2068 daytime photosynthesis overcome the buoyancy from the gas vesicles, and cells sink to cooler, 2069 nutrient-rich water, which allows them to continue to grow and maintain dominance. Not all 2070 cyanobacteria species appear to be capable of producing gas vesicles, and even among similar 2071 species, differences in relative abundance and activity of gas vesicles is evident (Brookes, Ganf, 2072 and Oliver 2000).

2073 Disrupting the ability of cyanobacteria to maintain their position in the water column is a 2074 strategy employed by several cyanobacteria control methods. While some strategies do this by 2075 artificially mixing the water column, others may bind the cells with flocculants to sink them out 2076 of the euphotic zone. However, ultrasound is the only method that targets these specific 2077 structures, which are unique to the cyanobacteria and a few other bacterial groups.

2078 Ultrasound refers to a wide range of applications, so care must be taken to distinguish among 2079 technologies. Typically, ultrasonic generators produce a frequency (measured in megahertz, 2080 MHz), at a set power intensity (measured in watts per centimeter2), at a set duration (measured 2081 in time, typically minutes). High power ultrasound is used to destroy bacteria and plankton in 2082 applications such as treatment of wastewater (Wu and Mason 2017) and ship ballast (Holm et al. 2083 2008). Ultrasonic technologies intended for cyanobacterial control utilize high frequency sound 2084 waves to collapse gas vesicles (Rajasekhar et al. 2012).

2085 The technology appears first to have been used in the field early 2000s (Lee, Nakano, and 2086 Matsumura 2002), though it was first conceptualized earlier (Park et al. 2017). This exposure 2087 results in gas vesicle collapse but typically not complete lysis or degradation of the cell. 2088 Frequencies between 1.7 MHz and 20 kHz are typically used in some modulation (Hao et al. 2089 2004), with reported durations ranging from few second pulses to several hours (Park et al. 2090 2017). Effective removal of most HCB species appears to occur within 10 mins of exposure 2091 under laboratory conditions, though there is limited field data to support this observation (Park et 2092 al. 2017, Wu, Joyce, and Mason 2012). At high energies, however, ultrasound may also disrupt 2093 colonies and even break cell walls, thus inhibiting growth (Lürling and Tolman 2014), and some 2094 laboratory testing shows destruction of the cyanotoxin microcystin (Liu et al. 2018, Song et al. 2095 2005), probably by generation of free radicals (Joyce, Wu, and Mason 2010). However, the 2096 mechanisms responsible for these effects in lab settings may not apply directly to field 2097 application. Controlled laboratory conditions are rarely true to field conditions, where rainfall, 2098 water quality, water flow, turbulence, and water volume under sonic generators appear to play a 2099 vital factor in device performance (Park et al. 2017). Even under ideal conditions, energy

284 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

2100 transmission falls off quickly with increasing distance (Rajasekhar et al. 2012) and hence the 2101 technique has limited range.

2102 Under field conditions, effectiveness is thought to be dependent on generation of frequencies that 2103 match resonant frequencies of the gas vesicles (Rajasekhar et al. 2012). Unfortunately, 2104 manufacturers of commercially available devices consider such technical specifications to be 2105 proprietary information, so controlled independent testing is difficult. Studies that include 2106 technical details are rare and usually confined to laboratory conditions (Kong et al. 2019). 2107 Ultrasonic technologies are also not a short-term improvement technology, with many observed 2108 decreases or changes to ecological condition occurring over several weeks (Schneider, Weinrich, 2109 and Brezinski 2015, Villanueva et al. 2015). Off-target effects on other aquatic organisms 2110 including zooplankton (Lürling and Tolman 2014), insects, and vertebrates such as fish is 2111 possible, though documentation is limited.

EFFECTIVENESS NATURE OF HCB • Any mixing regime, though mixed systems • Effective on planktonic, gas vesicle could result in less contact time containing cyanobacteria • Toxic or non-toxic HCBs • Other aquatic algae can be targeted • Intervention strategy 2112

ADVANTAGES LIMITATIONS • Can move generators as needed and adjust • Does not appear to remove cyanotoxins frequency and length of exposure to target • If frequency causes cell lysis, extracellular different species cyanotoxin levels could increase • Some devices are coupled with real-time • Does not control nutrients sensors to measure effectiveness • Benthic blooms may still occur • Expensive and proprietary constraints prevent inspection of conditions, frequencies, etc. • High power treatments can affect other organisms

2113

2114

285 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

2115 COST ANALYSIS CASE STUDY EXAMPLES 2116 Financial cost depends on site-specific, 2117 Reservoir, New Jersey, United States: A geographical and lake morphology factors system of ultrasonic buoys was deployed in a 2118 and water conditions. For example, for a 2119 200 acre reservoir that historically had large water body, multiple generators may be blooms with taste and odor issues. The 2120 required to effectively prevent a bloom. The 2121 reservoir had previously used copper as its range and limitation, as well as the service primary treatment. 2122 and maintenance of each generator, must be 2123 factored into the cost of deploying this Reservoir 1 is a 200 acre water body with a 2124 technology. As this is a preventative mean depth of 17 feet. It is fed by a small 2125 technology that does not address nutrient brook and adjacent reservoir (Reservoir 2). 2126 input, a backup treatment option should be 2127 planned for blooms of cyanobacterial species Four ultrasonic buoys were deployed in May 2128 that do not form gas vesicles or are otherwise 2014 for the purpose of reducing total algae 2129 outside the treatment range of the technology. counts and concentrations of taste and odor 2130 compounds. While total numbers of algae 2131 Table 1: Ultrasound cost analysis per cells appeared to decline, it should be noted 2132 growing season. that copper applications were used along with the buoys. Also, technical specifications of ITEM RELATIVE COST the ultrasonic buoys (frequency, intensity) PER GROWING were not reported. SEASON Equipment $$ to $$$ General levels of cyanobacteria increased O&M Costs $$ to $$$ during the monitoring period; however, a OVERALL $$ to $$$ bloom of Aphanizomenon occurred once water from reservoir 2 was allowed to flow 2133 REGULATORY AND POLICY into reservoir 1 (August 13, 2014). A 2134 CONSIDERATIONS reduction in the bloom was not noted until September 17, 2015 and may have been due 2135 Some generators are able to utilize solar to either the length of exposure or the change 2136 panels for electricity, while others require in the ultrasound frequency to target 2137 shoreline tethering for power. Local Aphanizomenon spp. 2138 permitting for installation must also be 2139 considered. Potential impacts to zooplankton From Schneider et al. (2015). 2140 and other aquatic life must be considered.

286 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

2141 REFERENCES

2142 Brookes, Justin D., George G. Ganf, and Roderick L. Oliver. 2000. "Heterogeneity of cyanobacterial gas-vesicle 2143 volume and metabolic activity." Journal of Plankton Research 22 (8):1579-1589. doi: 2144 10.1093/plankt/22.8.1579. 2145 Hao, Hongwei, Minsheng Wu, Yifang Chen, Jiaowen Tang, and Qingyu Wu. 2004. "Cavitation Mechanism in 2146 Cyanobacterial Growth Inhibition by Ultrasonic Irradiation." Colloids and Surfaces B: Biointerfaces 2147 33:151-156. doi: 10.1016/j.colsurfb.2003.09.003. 2148 Holm, E. R., D. M. Stamper, R. A. Brizzolara, L. Barnes, N. Deamer, and J. M. Burkholder. 2008. "Sonication of 2149 bacteria, phytoplankton and zooplankton: Application to treatment of ballast water." Mar Pollut Bull 56 2150 (6):1201-8. doi: 10.1016/j.marpolbul.2008.02.007. 2151 Joyce, E. M., X. Wu, and T. J. Mason. 2010. "Effect of ultrasonic frequency and power on algae suspensions." J 2152 Environ Sci Health A Tox Hazard Subst Environ Eng 45 (7):863-6. doi: 10.1080/10934521003709065. 2153 Kong, Y., Y. Peng, Z. Zhang, M. Zhang, Y. Zhou, and Z. Duan. 2019. "Removal of Microcystis aeruginosa by 2154 ultrasound: Inactivation mechanism and release of algal organic matter." Ultrason Sonochem 56:447-457. 2155 doi: 10.1016/j.ultsonch.2019.04.017. 2156 Lee, T. J., K. Nakano, and M. Matsumura. 2002. "A novel strategy for cyanobacterial bloom control by ultrasonic 2157 irradiation." Water Sci Technol 46 (6-7):207-15. 2158 Liu, Cheng, Zhen Cao, Siyuan He, Zhehao Sun, and Wei Chen. 2018. "The effects and mechanism of phycocyanin 2159 removal from water by high-frequency ultrasound treatment." Ultrasonics Sonochemistry 41:303-309. doi: 2160 https://doi.org/10.1016/j.ultsonch.2017.09.051. 2161 Lürling, M., and Y. Tolman. 2014. "Beating the blues: is there any music in fighting cyanobacteria with 2162 ultrasound?" Water Res 66:361-373. doi: 10.1016/j.watres.2014.08.043. 2163 Park, Y., J. Pyo, Y. S. Kwon, Y. Cha, H. Lee, T. Kang, and K. H. Cho. 2017. "Evaluating physico-chemical 2164 influences on cyanobacterial blooms using hyperspectral images in inland water, Korea." Water Res 2165 126:319-328. doi: 10.1016/j.watres.2017.09.026. 2166 Rajasekhar, Pradeep, Linhua Fan, Thang Nguyen, and Felicity Roddick. 2012. "A Review of the Use of Sonication 2167 to Control Cyanobacterial Blooms." Water research 46:4319-29. doi: 10.1016/j.watres.2012.05.054. 2168 Reynolds, C. S., and A. E. Walsby. 1975. "Water-Blooms." Biological Reviews 50 (4):437-481. doi: 2169 10.1111/j.1469-185X.1975.tb01060.x. 2170 Schneider, Orren D., Lauren A. Weinrich, and Scott Brezinski. 2015. "Ultrasonic Treatment of Algae in a New 2171 Jersey Reservoir." Journal - AWWA 107 (10):E533-E542. doi: 10.5942/jawwa.2015.107.0149. 2172 Song, W., T. Teshiba, K. Rein, and K. E. O'Shea. 2005. "Ultrasonically induced degradation and detoxification of 2173 microcystin-LR (cyanobacterial toxin)." Environ Sci Technol 39 (16):6300-5. doi: 10.1021/es048350z. 2174 Villanueva, Maria V., Maria C. Luna, Maria I. Gil, and Ana Allende. 2015. "Ultrasound treatments improve the 2175 microbiological quality of water reservoirs used for the irrigation of fresh produce." Food Research 2176 International 75:140-147. doi: https://doi.org/10.1016/j.foodres.2015.05.040. 2177 Walsby, Anthony E., Paul K. Hayes, Rolf Boje, and Lucas J. Stal. 1997. "The selective advantage of buoyancy 2178 provided by gas vesicles for planktonic cyanobacteria in the Baltic Sea." New Phytologist 136 (3):407-417. 2179 doi: 10.1046/j.1469-8137.1997.00754.x. 2180 Wu, X., E. M. Joyce, and T. J. Mason. 2012. "Evaluation of the mechanisms of the effect of ultrasound on 2181 Microcystis aeruginosa at different ultrasonic frequencies." Water Res 46 (9):2851-8. doi: 2182 10.1016/j.watres.2012.02.019. 2183 Wu, Xiaoge, and Timothy Mason. 2017. "Evaluation of Power Ultrasonic Effects on Algae Cells at a Small Pilot 2184 Scale." Water 9:470. doi: 10.3390/w9070470.

2185

287 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

2186 ULTRAVIOLET (UV) EXPOSURE

2187 In-lake Intervention Strategy Limited Supporting Field Data

2188 Ultraviolet (UV) exposure is an advanced oxidation technique that is used most commonly to 2189 disinfect treated water in process level treatments, where this is a more established technique. 2190 UV exposure works by transferring electromagnetic energy from a UV bulb to stop organisms 2191 from reproducing by inactivating their DNA. UV-C (UV-C wavelengths, 190-280nm) light is 2192 typically used in treatment processes due to its short wavelength, which is highly energetic and 2193 has strong mutagenic effects on the DNA of most organisms (Pattanaik, Schumann, and Karsten 2194 2007). UV exposure has been experimentally shown to oxidize microcystins and 2195 cylindrospermopsin, but at extremely high doses that are not feasible for an in-field application 2196 (USEPA 2019). UV exposure has been shown to be effective at oxidizing cyanotoxins in 2197 production scale treatment operations when used in tandem with a catalyst such as hydrogen 2198 peroxide (Afzal et al. 2010).

2199 Use of UV exposures for control of an HCB in surface waters is not an established technique. 2200 Some studies have shown experimentally that UV exposure can inhibit HCB growth (Alam et al. 2201 2001, Sakai et al. 2007), but while Alam et al. (2001) reports that boats equipped with UV-lamps 2202 were used in several eutrophic lakes in Japan to control algal growth, detailed reports of field 2203 data could not be found. Currently, this approach is considered limited/emerging due to a lack of 2204 validated field applications specifically for HCBs. An alternative application strategy is the 2205 deployment of boats with UV-lamps to stunt the growth of an active bloom (as reported 2206 indirectly in Alam et al. 2001) does show some feasibility for smaller, shallow lakes. This 2207 approach has been piloted in Lake Tahoe, but to control invasive weeds (Tahoe Resource 2208 Conservation District 2018).

EFFECTIVENESS NATURE OF HCB • Water body type: lake/reservoir • HCB types: could be effective for • Surface area: small planktonic or benthic blooms • Depth: shallow • Repeating HCB; useful for drinking water • Water body use: drinking water treatment in reservoirs and other source (treatment), treated wastewater/effluent. waters with chronic, recurring HCB • Water bodies with low turbidity • Approach is non-targeted; other microbes and photosynthetic organisms could be susceptible to DNA damage (Pattanaik, Schumann, and Karsten 2007) • Potential as immediately effective strategy by suppressing cyanobacterial growth following exposure • Intervention strategy 2209

288 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

ADVANTAGES LIMITATIONS • UV exposure (UV-C) has been shown to • UV exposures alone are not effective at inhibit growth of Microcystis aeruginosa oxidizing cyanotoxins but may be effective for several days in lab studies, even at if used in tandem with a catalyst (e.g. relatively low doses (37 mW/s/cm-2) hydrogen peroxide) • Technique does not directly produce waste • Limited peer-reviewed evidence to support byproducts; note that there is some the use of UV exposures to control algal experimental evidence that UV exposures growth in lakes have the potential to photoconvert • Boat deployment requires that lamps be compounds such as pharmaceuticals depth-adjusted to accommodate the vertical (Canonica, Meunier, and von Gunten migration of cyanobacteria in the water 2008) column • Effectiveness can be dampened by turbidity and dissolved organic carbon content in water body (Afzal et al. 2010)

2210 2211 Figure 1: The boat built by Inventive Resources has a panel of UV lights that is lowered down to 2212 expose the aquatic invasive plants

2213 Figure source: Claire Cudahy/Tahoe Daily Tribune 2017.

2214 COST ANALYSIS

2215 Large scale use of UV treatment on a process scale is expensive, but less costly than other 2216 advanced oxidation and disinfection processes according to a cost analysis conducted by Dore et 2217 al. (2013). There is a lack of estimated cost analysis for UV exposure via boat, specifically for 2218 management of HCBs. Labor costs for use of UV exposure for invasive weed control in Lake 2219 Tahoe were estimated at $28,000 for UV-C Treatment system 160 ft2 across 1 acre (Tahoe 2220 Resource Conservation District 2018). Capital costs were not provided.

289 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

2221 Table 1: Process-level UV exposure cost CASE STUDY EXAMPLES 2222 analysis for per growing season. ITEM RELATIVE COST Laboratory-scale: Tao et al. (2010) conducted a PER GROWING laboratory study comparing the effects of UV-C SEASON exposure on the growth of Microcystis Material $$$ aeruginosa and three green algae taxa. UV-C exposures of 20–200 mJ cm−2 were shown to Personal Protective $$ suppress the growth of M. aeruginosa for 3–13 Equipment days following a dose-dependent pattern. Equipment $$$ Machinery $$$ Exposure to >100 mJ cm−2 resulted in the death Tools $$$ of a majority of exposed cells. Exposures Labor $$$ ranging 20-50 mJ cm−2 had sublethal effects. O&M Costs $$$ The three green algae taxa did not experience −2 TOTAL $$$ significant effects across the 20-200 mJ cm exposure range, suggesting that M. aeruginosa 2223 is more sensitive than other non-HCB taxa.

This suggests that UV-C treatment may represent an intervention strategy that is relatively specific and may have very minimal impact on the environment.

Figure 2: Figure adapted from Dore et al. 2013. Estimated cost curves for several treatment technologies for disinfection in water treatment (primarily drinking water and wastewater treatment). Actifloc and MF- UF are mechanical treatment approach utilizing pairings of clarification and filtration systems, Ozonation (SCOR) is an approach that uses ozone to oxidize microbes following several prefiltration steps, and UV Swift SC and UV Phox are UV-oxidation based processes in tandem with either a catalyst or a filtration system. Extended descriptions of each treatment technologies can be found with Dore et al. (2013).

290 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

2224 REGULATORY AND POLICY CONSIDERATIONS

2225 Use of UV exposure to treat HCBs in the field may require permitting and reporting. From the 2226 example of Lake Tahoe, permits were acquired from the Tahoe Regional Planning Agency and 2227 an authorization letter was obtained from United States Army Corps of Engineers. Other 2228 regulatory agencies (Lahontan Regional Water Quality Control Board and CA Dept of Fish and 2229 Wildlife) in the state were contacted and offered consent or requested incorporation of specific 2230 monitoring parameters was requested. The project also conducted and reported monitoring 2231 results (Tahoe Resource Conservation District 2018). Due to this technique not being fully vetted 2232 for applications in situ, a similar level of permitting and reporting would be expected in other 2233 water bodies piloting the technique. Process level applications of this technique would likely 2234 require permitting similar to other plants implementing this technique.

2235 REFERENCES

2236 Afzal, A., T. Oppenländer, J. R. Bolton, and M. G. El-Din. 2010. "Anatoxin-a degradation by Advanced Oxidation 2237 Processes: vacuum-UV at 172 nm, photolysis using medium pressure UV and UV/H(2)O(2)." Water Res 2238 44 (1):278-86. doi: 10.1016/j.watres.2009.09.021. 2239 Alam, Z. B., M. Otaki, H. Furumai, and S. Ohgaki. 2001. "Direct and indirect inactivation of Microcystis aeruginosa 2240 by UV-radiation." Water Res 35 (4):1008-14. doi: 10.1016/s0043-1354(00)00357-2. 2241 Canonica, S., L. Meunier, and U. von Gunten. 2008. "Phototransformation of selected pharmaceuticals during UV 2242 treatment of drinking water." Water Res 42 (1-2):121-8. doi: 10.1016/j.watres.2007.07.026. 2243 Dore, Mohammaed H., Rajiv G. Singh, Arian Khaleghi-Moghadam, and Gopal Achari. 2013. "Cost differentials and 2244 scale for newer water treatment technologies." International Journal of Water Resources ad environmental 2245 Engineering 5 (2):100-109. doi: https://doi.org/10.5897/IJWREE12.103. 2246 Pattanaik, Bagmi, Rhena Schumann, and Ulf Karsten. 2007. "Effects of Ultraviolet Radiation on Cyanobacteria and 2247 their Protective Mechanisms." In Algae and Cyanobacteria in Extreme Environments, edited by Joseph 2248 Seckbach, 29-45. Dordrecht: Springer Netherlands. 2249 Sakai, Hiroshi, Kumiko Oguma, Hiroyuki Katayama, and Shinichiro Ohgaki. 2007. "Effects of low- or medium- 2250 pressure ultraviolet lamp irradiation on Microcystis aeruginosa and Anabaena variabilis." Water Research 2251 41 (1):11-18. doi: https://doi.org/10.1016/j.watres.2006.09.025. 2252 Tahoe Resource Conservation District. 2018. Aquatic Invasive Plant Control Pilot Project Final Monitoring Report 2253 Tao, Y., X. Zhang, D. W. Au, X. Mao, and K. Yuan. 2010. "The effects of sub-lethal UV-C irradiation on growth 2254 and cell integrity of cyanobacteria and green algae." Chemosphere 78 (5):541-7. doi: 2255 10.1016/j.chemosphere.2009.11.016. 2256 USEPA. 2019. "Cyanobacteria and Cyanotoxins: Information for Drinking Water Systems." U. S. Environmental 2257 Protection Agency. https://www.epa.gov/cyanohabs/health-effects-cyanotoxins.

2258

2259

291 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

COST COMPILATION FOR SEVERAL MITIGATION STRATEGIES

Appendix 1. Compilation of costs (2020 $US) for a suite of mitigation strategies. References with the * are listed in USEPA (2015).

LOCALE WATER TREATMENT CAPITAL O&M TOTAL TOTAL/ REFERENCE BODY COSTS/ COSTS/ ESTIMATED ACRE ACRE DURATION OF EFFECTIVENESS

AERATION Onota Deep-hole 700 91 791 Berkshire Lake (617 system Regional MA ac) NA Planning Commission (2004)*

Lovers Hypolimnetic 1904 106 1795 Lake & Aeration MA Stillwater ENSR Pond (55.5 Corporation ac) 133 (2008)*

Lovers Artificial 2352 157 2509 Lake & Circulation MA Stillwater ENSR Pond (55.5 Corporation ac) 166 (2008)*

Twin Lake Solar Bee 7793 277 8070 (20 ac) Hypolimnetic MN Dispersal Chandler (2013)* 402

MN Twin Lake Bottom Bubbler 12992 1939 14931 (20 ac) 736 Chandler (2013)*

ALUM TREATMENT

Lovers 16100 0 18032 Lake & MA Stillwater 1202 ENSR Pond Corporation (28.25 ac) (2008)*

MN Keller 816 0 914 NA Barr (2005)* Lake (72 ac)

MN Kohlman 2240 0 2509 NA Barr (2005)* Lake (74 ac)

292 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

LOCALE WATER TREATMENT CAPITAL O&M TOTAL TOTAL/ REFERENCE BODY COSTS/ COSTS/ ESTIMATED ACRE ACRE DURATION OF EFFECTIVENESS

MN Spring 2533 0 2837 89-284 Barr (2005)* Lake (409 ac)

MN Twin Lake 3852 0 4314 2876 Chandler (19 ac) (2013)*

NY Cossayuna 648 0 726 145 The LA Group Lake (35 (2001)* ac)

Lake 3 yr treatment, 217 0 243 NA Osgood Mitchell assumed whole (2002)* SD (877 ac) lake treatment

Green 7261 0 8132 813 Herrera Lake Environmental WA (259) Consultants (2003)*

WA Lake Sediment 7765 0 8697 2174 Burghdorff & Ketchum Williams (25.5 ac) (2012)*

WA Lake Water column 1441 0 1614 1614 Burghdorff & Ketchum Williams (25.5 ac) (2012)*

WA Lake Alum+ 2991 $619(mon) 3350 167 Tetra Tech Lawrence monitoring (2004)* (330 ac)

WA Lake 13690 0 15333 1533 King County Hicks (4 (2005)* ac)

WI Cedar Alum 2 x/yr, 1964 0 2220 220 Cedar Lake Lake assume 1/2 lake Protection & (1120) Rehab District (2013)*

WI E. Alaska 4143 0 4640 NA Hoyman Lake (41) (2011)*

BARLEY STRAW

MD Lake 500 bales + 3200 85 0 1 1 Calculated Williston labor from Sellner et (67) al. (2015)

MN Twin Lake 619 0 31 31 Chandler (20 ac) (2013)*

293 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

LOCALE WATER TREATMENT CAPITAL O&M TOTAL TOTAL/ REFERENCE BODY COSTS/ COSTS/ ESTIMATED ACRE ACRE DURATION OF EFFECTIVENESS

BIOMANIPULATION

MN Twin Lake removing, 15713 0 15713 NA Chandler (20 ac) adding fish, mon (2013)* fish

DREDGING

Lovers 91100 0 91100 9110 ENSR Lake & Corporation MA Stillater (2008)* Pond (19)

E. Lake 180000 0 180000 NA Lake Linganore Linganore MD (~100 ac) Association (2018)

MN Keller 436 0 436 NA Barr (2005)* Lake (72 ac)

MN Kohlman 636 0 636 NA Barr (2005)* Lake (74 ac)

MN Twin Lake 142342 0 142342 NA Chandler (20 ac) (2013)*

NY Cossayuna 29305 0 29305 NA The LA Group Lake (35 (2001)* ac)

WA Lake 92595 0 92595 1852 Tetra Tech Lawrence (2004)* (330)

FLOCCULATION

CHN Lake Tai Kaolinite, soil 148-245 0 148-245 148-245 Pan et al. (2019)

CHN Lake Tai Kaolinite, soil + 3648-8197 0 3648- 3648-8197 Pan et al. capping 8197 (2019)

HERBICIDE TREATMENT

NY Cossayuna CuSO4 933 0 933 933 The LA Group Lake (35 (2001)* ac)

HYPOLIMNETIC WITHDRAWAL

294 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

LOCALE WATER TREATMENT CAPITAL O&M TOTAL TOTAL/ REFERENCE BODY COSTS/ COSTS/ ESTIMATED ACRE ACRE DURATION OF EFFECTIVENESS

MN Twin Lake 32480 0 32480 3864 Chandler (20 ac) (2013)*

PEROXIDE

MD Lake 350 lbs granular 486 0 486 97 Mattheiss et al. Anita H2O2 cmpd. (2017) Louise (5 ac)

MD Spahrs 550 lbs granular 275 0 275 NA Campbell and Quarry (7 H2O2 cmpd. Sellner (in ac) prep.)

OUTDATED METHODS AND METHODS WITH A VERY NARROW RANGE OF APPLICABILITY

I. Biochar: Proposed in several states, there is limited data to support its use as an HCB prevention or intervention strategy. Biochar is believed to actively bind to minerals and nutrients, and is some early reports indicate similar binding behavior to activated charcoal.

II. Biomanipulation: Proponents claim that addition of elements such as silica to encourage completing photosynthetic microbes such as diatoms may delay or prevent cyanobacterial blooms. A few studies have also been conducted using the addition of non-selective filter feeding organisms such as mussels and certain herbivorous fish. The addition of these taxa is believed to shift the food web to disfavor the growth of cyanobacteria; however, the addition of these organisms could encourage or enhance the growth of cyanobacteria. In general, manipulating the food web has cascading effects that often magnify outside the user’s original intentions. (For discussion see Triest et al. 2016).

III. Nitrogen addition: Proponents claim that adding nitrogen to alter the Nitrogen:Phosphorus ratio will disfavor the growth of cyanobacteria and favor other photosynthetic organisms. Eutrophication is a widespread problem so addition of nutrients of any kind is not considered to be a sustainable action.

IV. Shade balls or floating covers: Proponents claim that these shading strategies, originally deployed to prevent evaporation and reduce light-facilitated chemical reactions, will also shade out cyanobacteria. While these methods may have

295 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

limited application, they may not be practical for widespread use, especially in multipurpose water bodies.

V. Barriers, Weir Curtains, and Exclusion Devices: Planktonic cyanobacteria can form thick surface scums, and the accumulations can be exacerbated by wind action, wave action, and reservoir discharge hydraulics. One strategy for mitigating the effect of a bloom is simply to exclude it physically. A barrier can placed on or near the water surface to isolate and protect a high value location such as a swim beach or drinking water intake. While simple in principle, the concept has been difficult to implement, and it has not often been tested rigorously. The solution is probably not practical on a small scale, because engineering costs are high, but there are a few promising implementations in large drinking water reservoirs.

Figure 1: Weir curtain in Paldang Reservoir (Park et al. 2017).

Figure 2. Iron Gate Reservoir Barrier Curtain Design, and deployed (Peters 2017).

296 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

297 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

TEAM CONTACTS

[Place this appendix before the glossary. Include Team Leaders, PAs, and especially knowledgeable Team members who are willing to serve as contacts. For each contact, provide name, agency or affiliation, phone, and e-mail.]

Sample Contacts:

Angela Shambaugh, Team Leader Vermont Department of Environmental Conservation 802-490-6130 [email protected]

Ben Holcomb, Team Leader Utah Department of Environmental Quality 801.536.4373 [email protected]

Cherri Baysinger, Program Advisor Cymbella Consulting 573-441-2319 [email protected]

298 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

GLOSSARY

Adsorbed

Adhered to a surface, either chemically or electrostatically.

Algae

Plural of alga. Algae is a common term used to describe a highly variable group of photosynthetic organisms, often aquatic, that lack true stems, leaves, roots, and flowers. This term is applied to several taxonomic groups, including cyanobacteria.

Algaecide/Algaestatic

Compounds that kill or prevent growth of algae and cyanobacteria.

Allelopathy

The process of inhibiting competitors or grazers through the production of compounds.

Anatoxin-a

This cyanobacterial toxin is a bicyclic alkaloid which targets the central nervous system (neurotoxin). An analog (homoanatoxin-a) and derivatives have been identified. Anatoxin-a may be produced by species of, but not limited to, Dolichospermum, Oscillatoria, Planktothrix, Phormidium, and Aphanizomenon. It may be abbreviated as ATX.

Anatoxin-a(S)

Now known as guanitoxin. This toxin was originally associated with Anabaena. This cyanobacterial toxin is a guanidine methyl phosphate ester that can target nervous systems (neurotoxin) by irreversibly binding to the acetylcholinesterase enzyme, and causes symptoms including excess salivation.

Aplysiatoxin

This cyanobacterial toxin is considered to be a dermatoxin, as well as a potential carcinogen, based on primary impacts to the skin. Aplysiatoxins are produced by cyanobacteria including Lyngbya, Schizothrix, and Oscillatoria.

Bacteria

299 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Bacteria are single celled microscopic organisms that lack cell walls and an organized nucleus (prokaryotes). They are found in every habitat on the planet. Some are photosynthetic.

Benthic

Refers to the bottom of lakes, rivers and other water bodies. When referring to cyanobacteria habitats it can refer to sediment surfaces, but also pebbles, cobbles, boulders, and other hard surfaces (see also Planktonic).

Best Management Practices (BMPs)

Strategies that are implemented on a landscape to reduce influx of nutrients, sediments, and other possible pollutants to local receiving waters.

Biomass / biovolume

Respective mass or volume of cells in a unit volume of water (e.g., mg/mL). Typically calculated to determine the relative abundance of co-occurring phytoplankton of varying shapes and sizes. Can be also quantified as a pigment such as chlorophyll or phycocyanin.

Bloom

A rapid proliferation of algae or cyanobacteria. In the case of cyanobacteria, it is also used to refer to dense accumulations of these populations, such as a wind-driven scum or benthic mats floating to the surface.

Blue-Green Algae

A historic term used to describe cyanobacteria. The blue-green color of certain species of cyanobacteria is due to the pigment phycocyanin leading to the common usage of “blue- green algae”.

BMAA

Acronym for β-methylamino-L-alanine. Non-protein amino acid produced by some cyanobacteria that is hypothesized to be a neurotoxin and is linked to the development of neurodegenerative diseases. Although, that hypothesis is still under investigation and has not been uniformly accepted by the scientific community.

BOD

Biological oxygen demand, an indicator of oxidizable (decomposable) cells and dead material.

300 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Capping

The addition of a layer of material, such as sand or clay, to cover the bottom of a pond, lake, or reservoir to prevent resuspension of less dense fine particles, including flocculated (aggregated) and settled cyanobacteria.

Chlorophyll

The green pigment used for photosynthesis by all land and aquatic plants, algae, and cyanobacteria.

Clean Water Act, Section 303(d)

Section 303(d) of the CWA requires states to identify a list of impaired waters that fail to meet any of their applicable water quality standards. This list, called a 303(d) list, is submitted to Congress every 2 years, and states are required to develop a Total Maximum Daily Loads (TMDL) for pollutant(s) causing impairment for water bodies on the list.

Clean Water Act, Section 401

Section 401 of the CWA requires that any applicant for a federal license or permit to conduct any activity that “may result in any discharge” into navigable waters must obtain a certification from the state or tribe in which the discharge originates that the discharge will comply with various provisions of the CWA. The federal license or permit may not be issued unless the state or tribe has granted or waived certification. The certification shall include conditions necessary to assure that the permit will comply with the state’s or tribe’s water quality standards or other appropriate requirements of state or tribal law. Such conditions must be included in the federal license or permit.

Clean Water Act, Section 404

Section 404 of the CWA regulates the discharge of dredged or fill material into Waters of the United States (including wetlands). A federal or state authorization is required through a nationwide, regional, general, or individual permit.

Colony / Colonial

A group of loosely or tightly associated, genetically identical cells that may exist as a unit in the environment.

Cyanobacteria

A group of photosynthetic prokaryotic microorganisms, historically identified taxonomically as falling within the Kingdom Plantae. Cyanobacteria are currently considered more similar to gram-negative bacteria. These were previously known as blue- green algae.

301 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Cyanocide / cyanostatic

Compounds that inhibit cyanobacteria cell proliferation.

Cyanopeptides

Nitrogen-containing compounds similar to microcystin, but far less studied, that include cyanopeptolins, anabaenopeptins, microginins, aeruginosins, and aerucyclamide. Many of these compounds can inhibit cellular functions just as frequently, and at similar nanomolar concentrations in surface waters as more commonly known cyanotoxins.

Cyanotoxin

Toxin produced by cyanobacteria. These toxins include liver toxins (hepatotoxin), nerve toxins (neurotoxin), and skin toxins (dermatoxin). Also sometimes referred to as “algal toxin”.

Cylindrospermopsin

Cyanobacterial toxins which are tricyclic alkaloids and which are considered to be hepatotoxins based on primary impacts to the liver, but may also be considered cytotoxins (lyses cells) due to impacts on other organs as well. Several congeners and analogs have been identified. It may be abbreviated as CYN. Cylindrospermopsin may be produced by species of, but not limited to, Cylindrospermopsis, Aphanizomenon, Chrysosporum, Umezakia, Anabaena, Dolichospermum, Microseira (formerly Lyngbya), and Raphidiopsis.

Designated use

A legally binding definition that identifies an activity or purpose (“fishable/swimmable”) for a water body. The identification of designated uses informs protection and management through federal, state, and tribal water quality regulations as outlined in the Clean Water Act. Recreation, drinking water, and aquatic life uses are examples of common designated uses. States and tribes may also develop additional designated uses. To learn more, see Chapter 2 of the EPA Water Quality Standards Handbook: https://www.epa.gov/sites/production/files/2014-10/documents/handbook-chapter2.pdf

Disinfection

The processes by which water is treated to remove pathogens to produce drinking water or treat wastewater. Three common disinfection methods include chlorine, ultraviolet light, and ozone. This is the stage where dissolved cyanotoxins can be destroyed in the drinking water treatment process.

Drain field / Leach field

302 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

The part of a septic system downstream of the holding tank, which distributes nutrient enriched wastewater from the holding tank to the underlying soil.

Ecosystem service

Benefits that humans receive from nature.

ELISA

Acronym for enzyme–linked immunosorbent assay, which are antibody- or antigen-based screening tests, including those for cyanobacterial and algal toxins.

Enumeration

Laboratory method in which microscopic organisms including cyanobacteria are quantified by microscopy. Results are usually reported as cell densities (cells/mL) but may also be reported as natural units/mL, i.e. colonies, filaments/trichomes, or single cells which are an organism’s usual growth form.

Epilimnion

A well-mixed, less dense layer of water near the surface in thermally stratified water bodies. It generally overlies denser colder waters.

Eukaryotic

Referring to organisms, either microscopic or macroscopic, which have a membrane-bound nucleus and organelles (see also Prokaryotic).

Eutrophication

The increase in nutrients (nitrogen, phosphorus, trace materials) in a water body that leads to excessive growth of algae or cyanobacteria.

External loading

Nutrients that reach a water body from sources in its watershed, known as external sources (see also Internal Loading).

Extracellular

Present outside cells. In this document, typically used in reference to cyanotoxins that have been released from cells (see also Intracellular).

F 303 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Filament

Also known as trichome. It is formed by single algae cells that are joined to create a chain or filament. These filaments can be seen by the naked eye. A common morphology of many cyanobacteria including Anabaena, Dolichospermum, Aphanizomenon, Cylindrospermopsis, and many others.

Flocculation

The process of aggregating suspended cells through the addition of inorganic ballast (clays, soils) coated with a surfactant (binding agent) that induces cells to stick to the particles and sink out of the water column.

Gas vesicles

Gas filled structures in some prokaryotes that help in regulating buoyancy.

Glutaraldehyde

A potent preservative used in storage of field and laboratory samples for microscopy.

Guanitoxin

Currently proposed name for the neurotoxin originally named anatoxin-a(s) and abbreviated as GNT.

Harmful cyanobacterial bloom (HCB)

A rapid proliferation of cyanobacteria that may include cyanotoxins. It is also used to refer to dense accumulations of cyanobacteria, such as a wind-driven scum or populations at depth, including those on the bottom (benthic mats) which may float to the surface.

Hepatotoxin

Toxin with a primary target of the liver. For cyanotoxins, the most common example is microcystin (and its congeners).

Heterocyst

A specialized nitrogen fixing cell formed by some cyanobacteria. Nitrogen fixation is very sensitive to oxygen and the heterocyst structure creates an oxygen-free space. May also be referred to as a heterocyte in some cyanobacterial literature.

304 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Hydromodification

The alteration of the natural flow of water through a landscape, such as changes in land use or cover. Additionally, it often takes the form of channel modification, such as channelization.

Internal Loading

The release of nutrients from sediments within a water body. Nutrients from external sources may be taken up by organisms and incorporated into their cells or may sink and be held in the sediment by chemical processes. Dead algal cells can also settle and contribute to the sediment nutrient load. Under certain conditions, usually low oxygen levels at the sediment surface or extreme pH levels, nutrients can be released from the sediment to the water column (see also External Loading).

Intracellular

Present within cells. In this document, typically used in reference to cyanotoxins (see also Extracellular).

Jar Test

In this document, a “jar test” is a simple test for determining whether water contains planktonic cyanobacteria by letting water stand undisturbed in a jar. Planktonic cyanobacteria, if present, will eventually form a floating layer, and other algae will deposit on the bottom.

Legacy Nutrients

Surplus nutrients which have accumulated over a long period of time, such as those retained in groundwater and lake sediments (see also Internal Loading).

Lipopolysaccharide

Large molecules comprising a lipid and a polysaccharide that are a component of the outer membrane of mainly Gram-negative bacteria and cyanobacteria that may cause irritation, including skin rashes, eyes, ears, and gastrointestinal symptoms.

Lugol’s Solution

305 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

An aqueous solution of iodine and potassium iodide that is used as a fixative for staining and short-term storage of phytoplankton samples for microscopy. For longer term sample storage, a preservative like glutaraldehyde or formaldehyde should be added.

Lyngbyatoxin

A cyanotoxin that is a potential carcinogen and a known dermatoxin. Lyngbyatoxins are produced by cyanobacteria including Lyngbya.

Lyse (lysed, non-lysed)

To lyse a cell is to disrupt a cell membrane and therefore destroy a cell, releasing its contents into the environment.

Memorandum of Understanding (MoU)

A formal agreement between two or more parties. In the context of HCBs, an MoU is often used to clarify roles and responsibilities for responding to HCB incidents and other environmental interventions.

Microcystin(s)

These cyanobacterial toxins are monocyclic heptapeptides and considered to be hepatotoxins, based on primary impacts to the liver. Globally, microcystins are the most commonly occurring cyanobacterial toxins. As of 2020, more than 200 congeners (variants with different accessory amino acids) of microcystin have been identified. Microcystins are abbreviated as MC- followed by 2 letters designating the congener name, e.g., MC-LR which contains leucine (L) and arginine (R). Microcystins are produced by many cyanobacteria, including but not limited to species of Microcystis, Dolichospermum, Nodularia, Planktothrix, Fischerella, Nostoc, Oscillatoria, and Gloeotrichia.

Mucopolysaccharide

Compounds secreted by cyanobacteria in which some colonial forms grow, or which form sheaths around some filamentous forms; can also be referred to as exopolysaccharide (EPS).

Neurotoxin

Toxin with a primary target of the nervous system. The four major neurotoxic cyanotoxins (with their variants) are anatoxin-a, guanitoxin/anatoxin-a(s), saxitoxin, and possibly BMAA. Several producers include Cylindrospermopsis, Anabaena, Dolichospermum, Planktothrix, Aphanizomenon, Lyngbya, and Raphidiopsis.

306 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Nitrogen fixation, fix nitrogen

The process by which the gaseous molecular nitrogen from the air is converted into ammonia or related compounds that can be used for growth (called fixed nitrogen). Biological nitrogen fixation is carried out by very few cyanobacteria and nitrogen-fixing bacteria, and most other organisms depend on the nitrogen fixers for fixed nitrogen.

Nonpoint source

These sources of pollutant loading do not have a clearly identifiable source of nutrients that are delivered to a water body. Typically, these are delivered as a diffuse leakage or runoff across a broad area. Any source that does not meet the legal definition of a “point source” is defined as a nonpoint source (see also Point Source).

Pelagophyte

A specific group of algae with two flagella. In this document, it refers to the ‘brown tide’ organism Aureococcus anophagefferens, a 2-micrometer cell that blooms in coastal lagoons.

Photosynthesis/Photosynthetic

The biochemical process in which cyanobacteria, algae, and plants use solar energy to convert carbon dioxide and water to carbohydrates and oxygen.

Phycocyanin pigments/Phycocyanin

Blue-green water-soluble pigment which gives “blue-green algae,” or cyanobacteria, their name. Phycocyanin is an accessory pigment that assists the chlorophyll molecule in capturing light for photosynthesis.

Phycoerythrin

One of several accessory pigments that assist the chlorophyll molecule in capturing light for photosynthesis. They are found in some cyanobacteria as well as cryptophytes and red algae.

Phytoplankton

A general term referring to the small photosynthetic organisms floating in open areas of water. Phytoplankton may be unicellular or multicellular, and prokaryotic or eukaryotic.

Plankton/planktonic

Organisms that live in open water bodies and drift by the tides, currents, and wind. (see also Benthic). 307 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

Point source

Point sources are clearly identifiable conveyors of a pollutant to a water body, as defined in the Clean Water Act. Typically, it is a managed wastewater flow released to the environment by means of a pipe or other distribution system. Many point sources are managed under the National Pollutant Discharge Elimination System (NPDES) permitting (see also Nonpoint source).

Prokaryotic

Referring to microscopic, single-celled organisms lacking a membrane-bound nucleus and organelles, and which includes bacteria and cyanobacteria (see also Eukaryotic).

Remote sensing

The use of satellites, airplanes, drones, buoy or floating sensor packages, or underwater data collectors to observe and obtain information about the Earth’s surface and aquatic systems.

Respiration

The physical and chemical processes that produce energy in living cells. Oxygen is needed for this process and carbon dioxide is released as a waste product. Though cyanobacteria produce oxygen through photosynthesis during the day, they also respire and can rapidly remove oxygen from the water at night when very large blooms are present

Risk communication

Actions, words, and other messages, responsive to the concerns and values of the information recipients, intended to help people make more informed decisions about threats to their health and safety.

Risk communication is the formal and informal process of communication among and between regulatory agencies and organizations responsible for site assessment and management, and the various parties who are potentially at risk from or are otherwise interested in the site.

Saxitoxin

Cyanobacterial toxin, abbreviated as STX, that is highly polar, nonvolatile, tricyclic perhydropurine alkaloids and targets the central nervous system (neurotoxin) by binding to sodium channels. Also known as paralytic shellfish poisons/toxins (PSP/PST) as these toxins can accumulate in marine shellfish and cause paralytic shellfish poisoning in humans that consume them. These toxins are produced by dinoflagellate algae (typically marine 308 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

systems) and by cyanobacteria in freshwater systems. These freshwater producers may include Anabaena, Aphanizomenon, Planktothrix, Cylindrospermopsis, Lyngbya and Scytonema.

Source water (for drinking)

Surface water bodies from which water is designated for human drinking water purposes. Source water undergoes further treatment, typically at a water treatment plant, and finished water is distributed to consumers.

Sp./Spp.

Abbreviations for a single species (sp.) or multiple species within a genus (spp.).

Stick Test

A simple test for determining whether floating mats contain cyanobacteria or filamentous green algae, in which a stick is inserted into and withdrawn from a floating mat. If the stick appears to be covered with paint-like material, the mat is most likely cyanobacteria. If the mat material drapes over the stick like hair and it is green, it is most likely to be filamentous green algae. If the material drapes over the stick and is black, it is possibly the cyanobacterium Microseria wollei (formerly known as Lyngbya wollei).

Stratification/Stratified

The division of the vertical water column into distinct layers of different densities due to variations in salinity and temperature. Stratification due to temperature is referred to as thermal stratification, and is frequently observed in deep lakes. The warmer waters, being less dense, are found near the surface, and constitute the epilimnion. The colder, denser waters are found at the bottom, and constitute the hypolimnion. The epilimnion and hypolimnion are separated by a distinct, thin layer of water called the thermocline where the temperature changes more rapidly than in the overlying and underlying waters. While each vertical layer is well-mixed in itself, the different layers do not intermix, resulting in variations in water quality in the surface and bottom water. For example, the epilimnion could be oxygen rich during the summers, while the hypolimnion could be devoid of oxygen at the same time. The lit near-surface warm water generally supports phytoplankton photosynthesis and elevated concentrations of dissolved oxygen. Oxygen concentrations decline below the thermocline due to less light and lower photosynthesis or darkness and no photosynthesis, leading to bacterial decomposition consuming the available oxygen. The low oxygen, in turn, results in high release of nutrients from bottom sediments and accumulation below the thermocline (see also Internal Loading). The thermocline acts as a barrier for oxygen diffusion from the surface downward and nutrient diffusion upward. Cyanobacteria can control their buoyancy and migrate up in the day for surface light and down at night for near-thermocline nutrients, giving them a unique competitive advantage over many other phytoplankton.

Surfactant 309 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

A compound added to induce aggregation of particles by reducing the surface tension between them, such as polyaluminum chloride (PAC), chitosan. These help in flocculating particles, including cells.

Taste and Odor Compounds

Several cyanobacteria as well as some diatoms produce compounds that impart unsavory taste and odor to drinking water or fish tissue, including geosmin and methylisoborneol (MIB). These compounds often require substantial modifications in drinking water facility treatments.

Taxon

Plural = “taxa.” The general term for a unified group of organisms. Algal and cyanobacterial taxa are typically referred to by genus or species, but higher ranks for all species include Kingdom, Phylum/Division, Class, Order, and Family.

Taxonomy (taxonomist)

The science of classifying and identifying organisms into specific categories based on internal and external morphologies and more recently, genetic information.

Thermocline

A thin distinct layer of water between the well-mixed upper and lower waters (the epilimnion and hypolimnion, respectively) in a thermally stratified water body.

Water Quality Standards

Water quality standards (WQS) are provisions of state, territorial, authorized tribal or federal law approved by EPA that describe the desired condition of a water body and the means by which that condition will be protected or achieved. See the EPA website for more information on developing WQS - https://www.epa.gov/standards-water-body-health/what- are-water-quality-standards. EPA’s Water Quality Standards Academy is a free online tool to help you understand the key concepts - https://www.epa.gov/wqs-tech/water-quality- standards-academy

310 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

ACRONYMS sBMPs Best management practices

BMPDB Best management practices database

BOD Biological oxygen demand

CAFOs Concentrated animal feeding operations

CDC Centers for Disease Control and Prevention

COD Chemical oxygen demand

CSOs Combined sewer overflows

CWA Clean Water Act

CyAN Cyanobacteria Assessment Network

DNA Deoxyribonucleic acid, hereditary material

ELISA Enzyme-linked immunosorbent assay

GIS Geographic information system

HABs Harmful algal blooms

HCBs Harmful cyanobacterial blooms

ITRC Interstate Technology and Regulatory Council

LC/MS/MS Liquid chromatography/tandem-mass spectrometry

MPCA Minnesota Pollution Control Agency

MS4 Municipal separate stormwater sewer systems

N Nitrogen

NALMS North American Lake Management Society

NOAA National Oceanic and Atmospheric Administration

NPDES National Pollution Discharge Elimination System

NRCS Natural Resource Conservation Service

NST Nutrient source tracking

311 ITRC–Strategies for Preventing and Managing Harmful Cyanobacterial Blooms External Draft – June 2020

OCDWEP Onondaga County Department of Water Environmental Protection

OHHABS CDC’s One Health Harmful Algal Bloom System

P Phosphorus

PPCP Pharmaceuticals and personal care products

PPE Personal protective equipment

PWS Public Water Supply

RFU Relative fluorescence unit

SOPs Standard operating procedures

TP Total phosphorus

TMDLs Total maximum daily load

TN Total nitrogen

USACE United States Army Corp of Engineers

USDA United States Department of Agriculture

USEP United States Environmental Protection Agency

USGS United States Geological Survey

312