Duwamish River and Elliott Bay

KING COUNTY Combined Sewer Overflow Water Quality Assessment for the Duwamish River and Elliott Bay

SUMMARY

1 The river was alive with salmon. They rolled and The Duwamish Estuary: Yesterday and Today products we use in our households and busi- splashed everywhere. I Why don’t we see a variety of fish and wildlife in nesses, and the crops we could hear them in the the Duwamish River and Elliott Bay in Seattle today? grow eventually find their The answer is complicated. Much is uncertain. But fog, and some I could way into our water bodies one thing we know for sure. Our activities have see, huge shadows that through sewers, leaky dramatically changed the water bodies in the area. septic tanks, and stormwater climbed the air and Over the past 100 years, we’ve changed the shape, runoff. slipped back into the the location, and the physical features of Elliott Bay The Duwamish River and water so close to the and the Duwamish River by filling in wetlands, Elliott Bay are considered an dredging the bottom of the water bodies for easier boat I could have estuary – a place where fresh- navigation, building houses and businesses along touched them. water and marine waters mingle. shorelines, and diverting or eliminating streams and Estuaries support an abundance Richard Hugo, rivers that flow into these waterbodies. And we’ve The Real West of life. Young salmon stay in the changed the quality of the water that remains in Marginal Way, 1986 Elliott Bay-Duwamish River these water bodies. Past industrial practices, which estuary for a while in order to eat are no longer in use, have left a legacy of pollution in and build up strength before moving into open the sediments. Today, human waste, animal waste, marine water; perch, rockfish, sole, shrimp, crab, and the chemicals from the cars we drive, the and mussels live there year round; spotted sand-

TABLE OF CONTENTS

The Duwamish Estuary: Yesterday and Today ...... 2 Thank You King County would like to express its King County CSO Water Quality Assessment ...... 3 appreciation to staff and members of the Combined Sewer Overflow Water Quality Controlling CSOs ...... 4 Assessment Stakeholder Committee, the Water Environment Research Foundation Peer Conducting The Study ...... 5 Review Panel, Boeing, the Washington State Study Team...... 5 Department of Fisheries, and the National Marine Fisheries Service for all their hard work Study Approach ...... 6 and help on this project. Key Findings ...... 8 Health Risks To Aquatic Life ...... 9 COVER PHOTOS Health Risks To Wildlife ...... 9 Top: Elliott Bay Health Risks To People ...... 10 Bottom: Duwamish River From Eating Seafood ...... 10 From Activities ...... 10 Produced by the King County Department of Natural Resources Stakeholder Committee Conclusions Writer: Kathryn White, And Recommendations...... 11 King County Water Quality Planner Design: Betty Hageman Graphic Design What’s Next? ...... 11 AUGUST 1999 For More Information ...... 11

2 piper, bald eagle, great blue heron, and river otters untreated sewage mixed with stormwater to the feed and live in the area; and people use the area estuary during heavy rainstorms. King County is for activities such as fishing, shipping, airplane responsible for planning to construction, boating, swimming, SCUBA diving, reduce these combined sewer In portions of Seattle, as bird watching, and windsurfing. overflows (CSOs) to meet the in many older cities, both sewage and stormwater Due to human activities, the amount of flow and limits required by state regula- travel to a treatment plant the quality of the water in this estuary have tions. As we were making these through the same pipes. diminished significantly since the mid-1800s. As a plans we still did not have a clear result, fish and wildlife populations and our ability understanding of the dynamics During heavy or to use and enjoy the area have also diminished. of this complex estuary. To gain prolonged rains, pipes For example, commercial harvesting of shellfish is a better understanding of the and treatment plants no longer allowed in Elliott Bay. Over the past 25 estuary and the impacts of CSOs simply can’t handle such years, King County, businesses, environmental relative to other pollutant large volumes. To protect groups, tribal governments, and other agencies sources, we undertook an the treatment plants and have started to address these concerns by under- extensive study: King County avoid sewer backups into taking numerous pollution control efforts to Combined Sewer Overflow Water homes and businesses, improve water quality. However, pollutants from a Quality Assessment for the the “combined” sewers variety of sources continue to degrade the estuary. Duwamish River and Elliott Bay discharge their contents (hereafter referred to as “the directly to the nearest study”). Some of the questions body of water. These we looked at included: King County CSO Water Quality Assessment discharges are called • What is the existing quality combined sewer In a recent survey, you told King County that of the water and sediment? overflows (CSOs). protecting and enhancing water quality in the region is a very high priority for you. We agree. • What are the flow patterns Among the many sources of pollution in the in the water and how are chemicals dispersed estuary, the region’s oldest sewers still discharge and/or ingested by aquatic life, wildlife, and humans?

1854 1908 1985 Duwamish Estuary – Changes Over Time

Shallows and flats Tidal swamps Deep water Developed floodplain and shoreline Undeveloped floodplain and shoreline Mean low water

3 Denny Way Combined Sewer Outfall harmful to public health and aquatic life because they carry chemicals and disease-causing pathogens. In order to protect water quality and human health, King County has been steadily working toward meeting the Washington State Department of Ecology (Ecology) standard that restricts combined sewer overflows to an average of one untreated Disease-causing discharge per year at each CSO pathogens such as location. bacteria and viruses We have made tremendous are in the estuary. progress in reducing CSOs. Over Sources include the past ten years, the volume of agricultural practices, King County’s CSO discharges has stormwater runoff, been reduced from 2.4 billion failing septic systems, gallons to approximately 1.6 billion illegal sewer • What are the health risks to humans and other gallons on average per year. So far, connections, and creatures that come in contact with the estuary 10 out of 37 CSO locations now CSOs. Removing CSOs with CSOs and without CSOs? meet the state standard. Completed will reduce some of CSO control projects have cost over the risk of infection The study found • Will the waters and sediment become cleaner and safer as a result of our $60 million; another $200 million is from human clear evidence of CSO control efforts? If so, to what slated for current projects. The pathogens, most potential health extent? King County comprehensive sewer noticeably near the risks to aquatic life, plan calls for bringing the remain- Denny Way CSO. wildlife, and people This study, along with other envi- ing CSO locations to within the as the estuary exists ronmental programs and projects state standard by the year 2030, at today. These risks undertaken by King County and other an additional cost of approximately $311 million. agencies (e.g., the Green/Duwamish come from a The Elliott Bay-Duwamish River estuary includes variety of sources. Watershed Forum and organizations developing fish recovery plans), 15 CSO locations, which discharge approximately 1.4 Removing CSOs provide more understanding of how billion gallons of combined flow in each year of will reduce some CSO control projects complement average rainfall. Considering that the entire King risks, but others other environmental control programs. County system discharges a total of 1.6 billion will remain. This added information will be reviewed to assess CSO projects and priorities. The following Roof pages summarize how we conducted the study, what Drain Storm Combined System Drain we found, and further actions recommended.

Sanitary Drain Controlling CSOs Overflow CSOs are one contributor to the pollution in the COMBINED SEWER Elliott Bay-Duwamish River estuary. Even though the sewage being discharged is greatly diluted by stormwater, both CSOs and stormwater may be To Treatment Plant

4 Lake Union CSO WQA Study Area Magnolia

LEGEND

Denny Way King County CSO King County CSO Ð Limited to one event per year Sewage Conduit N Tunnel Section Elliott Bay Study Area King St SEATTLE Connecticut St

Lander St MERCER “....It is true that today Chelan Ave Hanford # 2 Harbor Ave this area is ISLAND Lake industrialized, but it was Duwamish Washington not always that way. Brandon St The Duwamish estuary Terminal 115 Michigan was once a vibrant West Michigan migratory route for East Marginal salmon runs. Let us not Puget 8th Ave

80165BHGD.FH7 think what we see today Sound Norfolk was always that way, or St

SEATTLE CITY LIMITS must be that way forever.” Puget Sound Action Team Representative

gallons per year, the 1.4 billion gallons discharged Conducting The Study into the estuary represents a very large portion of the system’s CSO volume. The frequency and The King County Combined Sewer Overflow Water volume of discharges in the estuary vary with each Quality Assessment for the Duwamish River and CSO location – ranging from 4 to 51 times and from Elliott Bay was undertaken from 1996 through 1998. 2 to 455 million gallons per year. The Denny Way A key objective of the study was to consider the CSO in Myrtle Edwards Park discharges the most interests of the variety of people and groups who use frequently and has the largest volume of the estuary. To achieve this objec- any of King County’s CSOs. Projects are tive, we sought a diversity of currently underway to control this CSO perspectives for the study. and another at Norfolk by 2003. As outlined in King County’s comprehensive Study Team sewer plan, King County plans to construct “The River is In addition to the core project several CSO control projects in the estu- a sacred river.” team – consisting of scientists, ary. However, the CSO program will be Duwamish Valley planners, engineers, and other reviewed every five years and potentially Neighborhood professionals – a stakeholder commit- revised as additional studies are under- Preservation Coalition tee and a national peer review panel taken. Representative

5 “We all have a right to lent their support to the study. The stakeholder • Computer expect a healthy committee – composed of representatives from local modeling. We communities, businesses, environmental organiza- developed and ran a environment both now tions, tribal governments, and computer model that and into the future. agencies – offered advice on could mathematically We, of today, do not technical matters, provided describe the water flow insight into issues, and shared and the addition, removal, have a right to destroy the visions of their respective movement, and behavior of the resources and “In my vision, a natural communities and organizations pollutants within the estuary. environment of the (the quotations included in this The model was used to community of plants future.”.... “We can’t document reflect some of the estimate the levels of selected and animals will co-exist values and visions of the stake- pollutants in the water and put things back to near with commercial and holder committee). Throughout sediment of the estuary as perfect, but we can recreational uses in a the study, committee members they exist today and after improve on what we are donated large amounts of time removal of CSOs. healthy, sustainable doing. It has been and expertise in attending • Risk Assessment. We condition....The proven time and again, meetings and workshops, in conducted a risk assessment important thing is to gathering information, in review- to get an idea of whether and ‘the healthier the have the ecological ing and commenting on papers how these estimated levels of environment, the and reports, and in making environment robust pollutants (chemicals, metals, healthier the economy.” recommendations. enough to thrive disease causing organisms, Rainier Audubon The national peer review and other water quality Society Representative alongside the existing panel – composed of experts in parameters) could harm the and future development the fields of risk assessment, aquatic life, wildlife, and of the area.” CSO management, mathematical people that use the estuary. Boeing Representative modeling, and aquatic toxi- From the community of animals that lives in the cology – ensured that the study estuary, the project team and the Stakeholder used the best possible science. Committee selected species that could represent the The panel was coordinated by the Water Environ- whole community. The study consid- ment Research Foundation Wet Weather Peer ered water-dwelling and sediment- The Elliott Bay- Review Program. dwelling organisms, as well as Duwamish River wildlife and people who may come in estuary is influenced Study Approach contact with the water or sediments. by Puget Sound tides The King County Combined Sewer Overflow Water For water-dwelling organisms, and currents and by Quality Assessment for the Duwamish River and salmon (chinook, coho, and chum) freshwater flows from Elliott Bay consisted of three main tasks: represented migrating fish and English sole represented fish that the Green River. By • Collecting and analyzing live in the estuary year-round. modeling this Benthic organisms are samples. We collected and Sediment-dwelling organisms complex system, the the small creatures analyzed over 2,000 samples to (benthos) were considered because study team was able that live in and on top identify the type and level of their health and diversity are impor- to use computers to of sediments. They are pollutants in the water, sediment, tant both as indicators of the pollu- show what happens often the food for and tissues (including samples tion in the sediment and as indicators to pollutants from six of the CSO locations in birds and fish. of the health of other animals that entering the system the estuary). feed on these organisms. The wildlife from a variety of considered included river otters, sources. spotted sandpipers, blue herons, and

6 Sampling in the Duwamish River “This system is not a bald eagles. Finally, the ways wilderness. It is an that people may come in contact with pollution were urban environment. identified as fishing, swimming, However, the standards SCUBA diving, windsurfing, [for] its upkeep should and eating fish from the area. not be lowered. The A critical part of the study practical achievement of was to carefully consider which pollutants to analyze for and these standards may be which aquatic life and wildlife limited by the historic and human activities to con- burden which may take sider as representative of decades to eliminate.” potential health risks. The list EPA Region 10/ of pollutants covers chemicals Risk Evaluation and metals that can enter the Representative estuary from CSOs, stormwater runoff, and other sources. The list also covers three of the microscopic organisms that may be found in human and animal wastes and that can serve as indicators of the risk of infection: fecal coliform (general indicator of the presence of pathogens), rotavirus (representative of human intestinal viruses), and Giardia (which may cause diarrhea in humans). Added to the list are non- Chemicals & Metals Studied Pyrene pollutant water quality indicators Total Polychlorinated 1,4-Dichlorobenzene and physical disturbances, such as In a risk assessment, Biphenyls (PCBs) 4-Methylphenol scientists estimate Tributyltin (TBT) the temperature and salinity of water Arsenic the likelihood of Zinc and the scouring and deposition of Benzo(a)anthracene sediment. harm that could Benzo(a)pyrene result from specific Microbes Studied The study combined a great deal Benzo(b)fluoranthene of information collected through activities. The Fecal coliforms Benzo(g,h,l)perylene sampling, analysis, and modeling to public and elected Giardia Benzo(k)fluoranthene attempt to answer these questions: officials can use Bis(2-Ethylhexyl)phthalate Rotavirus these estimates to • How often do aquatic life, Cadmium help make informed wildlife, and people come in Chrysene Physical Changes Studied decisions on how Copper contact with pollutants? Total Suspended Solids best to improve the Dibenzo(a,h)anthracene • How are they exposed to the Scouring quality of our Fluoranthene pollutants (such as through Sedimentation waters. Indeno(1,2,3-cd)pyrene contact or ingestion of the Displacement Lead Salinity sediments and water and/or by eating fish or Mercury Dissolved Oxygen shellfish)? Nickel PH • How could they be harmed (such as decreased Polycyclic Aromatic Temperature reproduction, death, cancer, and other non- Hydrocarbons (PAHs) cancer illnesses)? Phenanthrene • What is the toxicity of the pollutants (the level known to affect health)?

7 Key Findings The accompanying tables show the major study findings in terms of the health risks to people, Major objectives of the study were to determine wildlife, and aquatic life from living in and being in existing conditions of the Duwamish River and contact with water, sediment, and food in the estu- Elliott Bay with CSOs and the conditions of these ary. The tables also include information on the water bodies if CSOs were eliminated. It was be- effect that removing CSOs will have on reducing yond the scope of this study to look at the specific health risks. For most risks, removing CSOs will impacts of other pollutant sources such as have little impact. However, removing CSOs will stormwater run-off, agricultural sources, and leaky reduce risk of infection from human pathogens, septic tanks. More research would need to be most notably near the Denny Way CSO (which will undertaken to specifically categorize the impacts of be controlled by 2003). Removing CSOs will also each of the other sources. reduce risks to sediment-dwelling organisms near the CSO discharges.

Our Use of Chemicals Impacts Risk

1,4-dichlorobenzene Mercury Toilet deodorizing blocks, mothballs, fumigants, and Electrical equipment, dental fillings, and (in the past) used chemical manufacturing as a fungicide Arsenic Polycyclic Aromatic Hydrocarbons (PAHs) Naturally occurring in Puget Sound water – other By-products of internal combustion engines, automobile possible sources include pesticides, manufacturing, and fuels, lubricants, and other sources the electronics industry Polychlorinated Biphenyls (PCBs) Bis(2-ethylhexyl) phthalate Coolants and lubricants in transformers, capacitors, and Plastics manufacturing – can be found in toys, vinyl other electrical equipment upholstery, shower curtains, adhesives, and coatings Tributyltin (TBT) Copper Antifouling agent in marine paints, a wood and paper Manufacture of metals products, drinking water pipes, preservative, and sometimes found in disinfectants fungicides, and preservatives Zinc Lead Rust preventatives, dry cell batteries, pennies, and metal Batteries, gasoline additives, paints, roofing materials, alloys caulks, ammunition, and solder

8 Health Risks To Aquatic Life

Risks Today With CSOs Effect Of CSO Removal WATER-DWELLING ORGANISMS (risk refers to No predicted reductions in risks for water-dwelling growth, reproduction, and mortality) organisms. Chemicals: Minimal potential risks from chemicals or other water quality indicators. Any potential risks are below Environmental Protection Agency (EPA) levels. SEDIMENT-DWELLING ORGANISMS (risk refers to Some predicted reductions in risks to sediment- reduced biological diversity and increased numbers dwelling organisms near the CSO discharges. No of pollution tolerant species) predicted reductions elsewhere in the river and the Chemicals: Potential risks from several chemicals bay. in sediments. •Most important cause of potential risk from No predicted reductions in risks from PCBs or TBT. PCBs and TBT. These chemicals generally come from sources other than CSOs. •Low risks from bis (2-ethylhexyl) phthalate, No to slight predicted reductions in risks from mercury, and PAHs. bis(2ethylhexyl) phthalate, mercury and PAHs in sediment near CSOs. •Low risks from 1,4-dichlorobenzene. Predicted reduction in risk from 1,4-dichlorobenzene. Organic enrichment: Localized increase in Possible increase in the variety of benthic organisms benthos that flourish in organic-enriched areas near CSOs as the result of decrease in organic matter. and decrease in benthos that are less tolerant of organic enrichment. Organic enrichment includes decomposing matter such as human waste, leaves, dead fish, bacteria, fecal coliforms, fats, oils, etc. Sedimentation and Scouring: Localized areas of Possible reduction in impacts of localized scouring sedimentation and scouring that would affect the and sedimentation may be small compared to the benthic community. overall scouring impacts of the river and sediment from other sources.

Health Risks to Wildlife

Risks Today With CSOs Effect Of CSO Removal Spotted sandpiper: Apparent relatively high risks No predicted reductions in risks to wildlife from chemicals in their food, particularly lead but as other sources contribute the majority of also copper, PCBs, and zinc. These chemicals may the risk-related chemicals. effect behavior, growth, and reproduction in animals. River otter: Some possibility that lead from food and sediments would be high enough to possibly impact reproduction. Also, an apparent risk associated with arsenic which could impact reproduction. Bald eagle and great blue heron: A lower possibility that lead from food and sediment might be high enough to possibly impact reproduction.

9 Health Risks to People

Risks Today With CSOs Effect Of CSO Removal FROM EATING SEAFOOD Chemicals: Potential risks, most notably from exposure to No predicted reductions in risks for people from chemi- PCBs and arsenic. Risks from arsenic are about the same cals in seafood. as for eating fish from Puget Sound sites we used as reference sites for this study. Cancer risks from chemicals: •Relatively high lifetime risk of developing cancer from No predicted reductions in cancer risks because most exposure to arsenic and PCBs for people who eat seafood PCBs and arsenic come from sources other than CSOs. from the area every day (about 1 person in 1,000 to 1 person in 100, depending on the type of seafood). •Lifetime cancer risk greater than 1 person in 1,000,000 No predicted reductions in cancer risks because most for people who catch and eat seafood from the area on PCBs and arsenic come from sources other than CSOs. average about two times per month (a fairly common occurrence, according to our survey). [One chance in a million is a commonly used regulatory threshold for acceptable cancer risk.] •Cancer risks caused by PCBs in sole are about 20 times No predicted reductions in cancer risks because most higher in the Duwamish River than in Elliott Bay and PCBs and arsenic come from sources other than CSOs. nearly 10 times higher in Elliott Bay than in reference Puget Sound sites. Other risks from chemicals: There are other risks from No predicted reductions in risks of non-cancerous health PCBs and arsenic for people who eat seafood from the effects because most PCBs and arsenic come from river and bay every day. Examples include effects on the sources other than CSOs. neurological system, immune system and skin. Pathogens: Fecal coliform levels indicate potential risks of Potential risks of infection from shellfish consumption will infection from shellfish consumption. decrease slightly, but risks will continue to exist because fecal coliforms also come from sources other than CSOs. FROM ACTIVITIES Chemicals: •Net fishing: Potential lifetime cancer risks of about 1 No predicted reductions in risks because most PCBs and person in 100,000 from arsenic and PCBs in sediments arsenic come from sources other than CSOs. for people who net fish in the Duwamish River 90 times per year. •Swimming: Potential lifetime cancer risks above 1 No predicted reductions in risks because most PCBs and person in 1,000,000 from arsenic and PCBs in arsenic come from sources other than CSOs. sediments for young children who swim 24 times per year at Duwamish Park in the Duwamish River and Duwamish Head in Elliott Bay. •Windsurfing and SCUBA diving: Potential lifetime Health risks do not change because PCBs and arsenic cancer risks are less than 1 person in 1,000,000 for come from sources other than CSOs. people who windsurf in Elliott Bay or SCUBA dive at SeaCrest Park as frequently as 24 times a year. Pathogens: •Fecal coliform levels indicate potential risks of infection No predicted reductions in risks from fecal coliform from direct exposure during fishing, swimming, concentrations because fecals also come from sources windsurfing, and SCUBA diving. other than CSOs, except near the Denny Way CSO location where some risk reduction is predicted. •During CSO discharges, risks of infection from Giardia Risks of infection from Giardia and viruses due to CSOs and viruses due to CSOs could be as high as 1 person will be eliminated, but the level of risk from other in 100 during all activities studied. These risks of sources remains unknown. infection from CSOs decrease to less than 1 person in 1,00010 within 6 hours after discharge. 10 Stakeholder Committee – Maintain diligence in developing and implementing Conclusions And Recommendations protective environmental standards • Conduct additional water quality studies to further The Stakeholder Committee reviewed the study’s refine our understanding of risks as well as to develop, findings and associated uncertainties, drew conclusions implement, and continually update the comprehensive from their interpretations, and made recommendations. control program. The Committee’s most important interpretation of the findings is that the existing environmental quality of the area poses a serious problem. Four important conclusions emerged from this interpretation: What’s Next? • Existing sediment quality and associated risks to This study represents a major step in working toward people, wildlife, and aquatic life in the estuary are creating an estuary that people, aquatic life, and wildlife unacceptable. can enjoy without unacceptable risks to their health. It is • Levels of human pathogens and fecal coliforms in the the first time that the entire area has been examined in estuary are unacceptable. such depth. The study helped to identify the extent of the problem today and with reduction of CSOs, but • Controlling CSOs according to the King County additional information must be gathered so that King comprehensive sewer plan will improve some aspects County and other jurisdictions can start to implement of environmental quality. broader solutions to the complex problems of the • Even if CSOs are completely eliminated, overall estuary. We need to learn more about the specific environmental quality will continue to be contributions of pollutants from various sources and the unacceptable. best ways for controlling these sources in a cost-effective Following these conclusions, the major recommen- manner. The computer model and information from the dation that emerged from the Stakeholder Committee is risk assessment will be used to support the development that a comprehensive regional program should be of future studies and projects. implemented to bring the river, its tributaries, and the King County is committed to protecting public health bay to acceptable quality and risk levels. The Stake- and the environment. Thus, King County’s comprehen- holder Committee recommendations included: sive sewer plan outlines wastewater projects to be • Complete the comprehensive regional program at the constructed over the next 30 to 40 years. This study, earliest possible date, but no later than 2030. along with other environmental programs and projects undertaken by King County and other agencies (e.g., the • Adopt an integrated approach that includes Green/Duwamish Watershed Forum and organizations participation by multiple jurisdictions. developing fish recovery plans), provides a greater • Include CSO control and the following actions in the understanding of how CSO control projects complement program: other environmental control programs. CSO projects – Control stormwater and non-point (based on a wide and priorities will be reassessed every five years as more variety of human activities) sources of information becomes available. contaminants – Restore habitat at some sites For More Information – Conduct public involvement and education programs For more information or to schedule a presentation on this study, please contact Sydney Munger, CSO – Remediate the sediment at some sites WQA Project Manager, at 206-296-1970 or e-mail – Control permitted discharges at [email protected]. – Periodically monitor the water quality to establish For copies of our documents, you can also visit our trends website at: http://splash.metrokc.gov/wlr/ waterres/wqa/wqpage.htm

pollutant sources? pollutant

compared to other to compared

impacts of CSOs of impacts

What are the are What

SUMMARY

Duwamish River and Elliott Bay Elliott and River Duwamish

Water Quality Assessment for the for Assessment Quality Water

Combined Sewer Overflow Sewer Combined KING COUNTY KING

This information is available in accessible formats on request at PRINTED ON RECYCLED (206) 684-1714 or PAPER (206) 296-0100 (TDD) 80165BHGD.PM6

King County BULK RATE Department of Natural Resources U.S. POSTAGE Wastewater Treatment Division King Street Center PAID 201 S. Jackson St., MS/KSC-NR-0503 SEATTLE, WA Seattle, WA 98104-3855 PERMIT NO. 836