GSI Manual: Volume V - Operations, Maintenance and Inspection

Green Stormwater Infrastructure Manual Volume V:

Operations & Maintenance

July 2015

GSI Manual: Volume V – Operations & Maintenance

This is the fifth volume in a 5-volume series for the GSI Manual. Please consult other volumes for additional information:

VOLUME:

I Project Initiation / Partnering Framework

II SPU’s Options Analysis / WTD’s Problem Definition Phase

III Design Phase

IV Construction & Commissioning

V Operations & Maintenance

This document was prepared and compiled by SvR Design Company for Seattle Public Utilities (SPU) and King County Wastewater Treatment Division (WTD) for the GSI Program (SPU Contract C12-004). Additional contributors to this document included representatives from SPU, WTD, and PRR (Section 10 – Public Engagement). This document includes documentation relevant to GSI in the right-of-way from the Washington State Department of Ecology Guidance Document “Western Washington Low Impact Development (LID) Operations and Maintenance” 7/2013; generally these excerpts are in italics.

For revisions or comments on this document, contact:

Seattle Public Utilities: Tracy Tackett, PE, [email protected]

Drena Donofrio, PE, [email protected]

KC Wastewater Treatment Division: John Phillips, [email protected]

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Vol-V_GSI_OM_Manualdraft_Rev8_10_2015.Docx

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Vol. V - Operations, Maintenance Table of Contents SECTION 1. Introduction to GSI Operations and Maintenance for Right-of-Way Projects ...... 1-1 1.1 Purpose and Regulatory Context ...... 1-1 1.2 GSI – A New Infrastructure ...... 1-2 1.3 Maintaining within Public View ...... 1-2 1.4 Right-of-Way Context ...... 1-3 1.5 Coordination with O&M, GIS and Asset Management Staff during Design . 1-3 1.6 Transition from Construction & Commissioning Period ...... 1-4 1.7 Differentiating Operations, Maintenance and Annual Inspection ...... 1-4 1.8 GSI Construction Period Maintenance ...... 1-4 1.9 GSI Maintenance Guidance Tables ...... 1-5 1.10 Acceptable / Unacceptable Guidance ...... 1-6 SECTION 2. Operations ...... 2-1 2.1 Defining Parameters and Resources ...... 2-1 2.2 Contract Coordination for Commissioning ...... 2-2 2.3 Contract Coordination for Construction Phase Establishment of Plantings . 2-3 2.4 Performance Standard ...... 2-3 2.5 GIS Based Asset Tracking for GSI Facilities ...... 2-4 2.6 Regulatory Reporting; Agency Reporting and Updates ...... 2-4 2.7 Staffing ...... 2-4 2.8 Training ...... 2-5 2.9 Equipment ...... 2-6 2.10 Materials ...... 2-6 2.11 Pavement Surfacing Materials for Repair/Replacement ...... 2-7 2.12 Plant Replacement Materials...... 2-7 2.13 Other Materials Required during Plant Replacement ...... 2-9 2.14 GSI Facility Component Corrective Actions ...... 2-10 2.15 Removal of Voluntary GSI Facilities ...... 2-11 2.16 Coordination with Other Right-of-Way Uses, Policies and Programs ...... 2-11 2.17 Emergency Management: Response ...... 2-12 2.18 Update Risk Management ...... 2-12 2.19 Feedback Loop to Update GSI Manual ...... 2-13 2.20 Public Information ...... 2-13 SECTION 3. Maintenance of Bioretention Surface Facilities...... 3-1 3.1 Overview ...... 3-1 3.2 Establishment Period ...... 3-1 3.3 Maintenance for Established Facilities ...... 3-2 3.4 Maintenance for Specific Components within Facility ...... 3-2 3.5 Future ...... 3-3 SECTION 4. Maintenance of Structures and Subsurface Storm Drainage ...... 4-1 4.1 Overview ...... 4-1 SECTION 5. Maintenance of Deep Infiltration Infrastructure Placeholder ...... 5-1 5.1 Overview ...... 5-1 5.2 Underground Injection Control Wells for Stormwater ...... 5-1

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5.3 Screen Wells ...... 5-2 5.4 Drilled Drains ...... 5-2 5.5 Pit Drains ...... 5-3 SECTION 6. Maintenance of Permeable Pavements ...... 6-1 6.1 Overview ...... 6-1 6.2 Components of Permeable Pavement System ...... 6-1 6.3 Sidewalks ...... 6-1 6.4 Pervious Concrete Neighborhood Streets/Alleys ...... 6-2 6.5 Future ...... 6-2 SECTION 7. Outsourced and Stewardship Maintenance ...... 7-1 7.1 Overview ...... 7-1 7.2 Outsourced and/or Work Order Contracts ...... 7-1 7.3 Stewardship ...... 7-1 SECTION 8. Storm Events, Extreme Weather or Emergency Maintenance ...... 8-1 8.1 Storm Events ...... 8-1 8.2 Extreme Weather ...... 8-1 8.3 Spills ...... 8-2 8.4 Vandalism ...... 8-2 8.5 Vehicular Damage ...... 8-2 SECTION 9. Inspection ...... 9-1 9.1 Overview ...... 9-1 9.2 Regulatory ...... 9-1 9.3 Record Keeping ...... 9-1 9.4 Asset Management ...... 9-1 9.5 Complaint-Based ...... 9-1 9.6 Role of Inspector ...... 9-2 SECTION 10. Public Engagement ...... 10-1 10.1 Purpose and Objective ...... 10-1 10.2 Outreach Tools ...... 10-2 10.3 Work Plan ...... 10-3 10.4 Training and Handoff ...... 10-3 10.5 Reporting ...... 10-4 SECTION 11. Voluntary Installations - Future ...... 11-1 11.1 Overview ...... 11-1 11.2 Tracking ...... 11-1 11.3 Inspection...... 11-1 SECTION 12. Maintenance Agreements and Related Policies-Future ...... 12-1 12.1 Overview ...... 12-1

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List of Tables Table 2-1: Plant Material Requirements & Considerations ...... 2-8 Table 2-2: Other Planting Component Requirements & Considerations ...... 2-9 Table 3-1: Component Examples ...... 3-3 Table 10-2: Work Plan Draft Outline ...... 10-3

List of Figures Figure 1: Concept of Typical Bioretention in Street Right-of-Way Context ...... 1-3 Figure 2: Sample Page from the Routine Maintenance Guidance for Mature GSI in the Right-of- Way (Appendix A) ...... 1-5

List of Appendices Appendix A: Routine Maintenance Guidance for Mature GSI in the Right-of-Way Appendix B: Establishment Period Maintenance Guidance for GSI in the Right-of-Way Appendix C: Major Corrective Action and Long-Term Maintenance Guidance for GSI in the Right-of-Way Appendix D: Images: Routine Maintenance Acceptable/Unacceptable Examples Appendix E: GSI Maintenance Checklists – Examples SPU and WTD Appendix F: GSI Maintenance Work Order Specification – Example WTD Appendix G: Planting Guidance for Trees and Vegetation Appendix H: Comparison of Watering Methods Analysis Example WTD Barton CSO Control Project Appendix I: Draft King County Integrated Pest Management Document Appendix J: GSI Maintenance Resources and Reference List Appendix K: Roadside Bioretention Cell Care Guide

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List of Abbreviations* *See COS Standard Plan 002 for other General Abbreviations used for street improvement plans in City’s ROW.

Term Abbreviation Definition amsl above mean sea level bgs below ground surface BMP Best management practices BOD Basis of Design CB catch basin COS City of Seattle CSO Combined Sewer Overflow DS&G SPU’s Design Standards & Guidelines Ecology Washington State Department of Ecology ECY Ecology FAQ Frequently Asked Questions ft foot (or feet) gpd gallons per day gph gallons per hour GDR Geotechnical Design Report GIS Geographic Information System GSI Green Stormwater Infrastructure IT Information Technology LA Landscape Architect LEED Leadership in Energy and Environmental Design lf linear feet LID Low Impact Development (often interchanged with GSI) LTCP Long-Term Control Plan MH maintenance hole MOA Memorandum of Agreement MOU Memorandum of Understanding NDS Natural Drainage System NG Neighborhood Greenways NPDES National Pollutant Discharge Elimination System O&M Operations and Maintenance PC/PT point of curvature / point of tangency (on a horizontal curve) PDB Project Delivery Branch (SPU) PE Professional Engineer PEG Public Engagement Guidelines PEP Public Engagement Plan PMP Project Management Plan

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Abbreviations Continued Term Abbreviation Definition PSE Puget Sound Energy ROW right-of-way ROWIM Right-of-Way Improvements Manual SCL Seattle City Light SDOT Seattle Department of Transportation SEPA State Environmental Policy Act SERP State Environmental Review Process SG Stage Gate SME Subject Matter Experts SOP Standard Operating Procedures SPU Seattle Public Utilities SWPPP Stormwater Pollution Prevention Plan S#.X.#.x ECY Special conditions for city and county NPDES Phase I & II permittees (eg S5.C.9.a) TESC Temporary Erosion and Sediment Control UIC Underground Injection Control WQ Water Quality WTD King County, Department of Natural Resources, Wastewater Treatment Division

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SPU Proposed Maintenance Work Type Abbreviations

Work Work Type Work Type Use Type Description RM Reactive Includes work required (perceived or actual) because something else Maintenance happened to trigger the need for the work; otherwise it would not have been done. PDM Predictive Inspection and Maintenance Maintenance PM program: Time or meter based inspections detecting the possibility of failure/condition assessment activities. Inspection may include cleaning or other minor maintenance.

Proactive PM Preventive Maintenance Maintenance PM program: Time or meter based maintenance

Proactive CBM Condition Based Maintenance performed as a direct result of inspections determining Maintenance that an asset’s condition has declined and/or that performance no longer meets defined minimum SPU standards.

Includes opportunitstic work performed to ensure assets are maintained to minimum SPU standards.

Proactive PROJ Project Intentional, pre-planned improvements, enhancements, new installations. Includes routine rehab.

OH Overhead Use of O&M resources for activities outside of their normal functions such as training, equipment maintenance/cleaning, meetings, ppe issues, etc.

DM Demand Work performed in response to external or internal request to perform non-repair/maintenance work, qa/qc, studies, new customer installations not associated with a project, etc.

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Section 1 Introduction to GSI Operations and Maintenance for Right-of-Way Projects

1.1 Purpose and Regulatory Context The purpose of this volume of the GSI Manual is to provide guidance and some standard procedures for operations and maintenance including annual inspections of constructed green stormwater infrastructure (GSI) facilities under the responsibility of SPU/WTD along streets in the City of Seattle (City) rights-of-way. Maintenance of regulated GSI Facilities is a requirement of the agencies respective permits: The Washington State Department of Ecology National Pollutant Discharge Elimination System (NPDES) Phase I and Western Washington Phase II Municipal Stormwater Permits includes provisions for municipalities to adopt and implement O&M programs and to facilitate proper O&M of LID BMP’s (S5.C9.a).

The end users of this manual may include staff from SPU, WTD, and/or their service contractors hired to provide assistance. The maintenance components generally follow the ECY 2013 O&M Guidance Document for consistency however as this manual’s focus is on the public works aspect of bioretention facilities in the right of way some elements may vary from ECY due to specific protocols for public work or function. .

This manual is a living document that should be updated periodically based on input from SPU and WTD staff and contractors as the strategies and techniques for GSI maintenance are refined with more facilities coming into practice. Updates are suggested in late 2016 after the latest series of GSI installations are completed and then in 2018 to include improved guidance from facilities completed in the 2017 time period. Feedback from the public should also be taken into account to promote continued public acceptance of GSI facilities. (See Section 10 and Appendix K)

This manual is intended to be used for various types of projects using GSI in the public right-of- way (ROW).

• For WTD-led projects: The project goal is to maintain the function of GSI technologies (such as roadside bioretention cells in a series and/or permeable pavements) to reduce combined sewer overflow (CSO) events (Flow Control BMP’s/Facilities) in combined sewer basins where the overflow is managed by WTD. • For SPU-led projects: The target function will vary depending upon the basin. GSI may be installed for creek protection, water quality treatment, flow mitigation, CSO control and/or other project targets (Stormwater Treatment and Flow Control BMP’s/Facilities).

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• For the projects in the right-of-way: ECY considers the following BMP’s to be Stormwater Treatment and Flow Control BMP’s/Facilities: Bioretention (ECY BMP T5.14B) and Permeable Pavement (ECY BMP T5.15). • Not intended: This manual is currently not intended to be used by other entities (e.g. private developers) for maintaining GSI in the City’s right-of-way as those installations may be under differing permit implications.

This is the fifth volume in a series for the GSI Manual. Consult with other volumes for additional information:

Volume I: Project Initiation/Partnering Framework Volume II: SPU’s Options Analysis/ WTD’s Problem Definition Phase Volume III: Design Phase Volume IV: Construction & Commissioning Volume V: Operations & Maintenance

In addition to reviewing materials that were prepared for SPU/WTD’s other GSI Manual Volumes, Appendix J includes references and resources both specific for the Operations and Maintenance of GSI, regulatory references and general resources.

1.2 GSI – A New Infrastructure Green Stormwater Infrastructure is still relatively new to the community as well as to public works staff in relation to other infrastructure systems such as water, sewer, electricity, roads, sidewalks and even trees. As a new infrastructure that is generally visible on the surface (as opposed to buried) there is a need to frame maintenance expectations and to be transparent to intended function. It is expected that there will be hurdles and a range of opinions. This document is intended to provide consistent guidance yet some flexibility in approach and outreach and will assist management and field staff in determining best methods for particular conditions. The information provided herein is moving toward standard operating procedures (SOPs) for GSI systems however, as this is still a new infrastructure, the tasks, steps, tools and materials used in maintenance are still being tested. Due to the relative newness of GSI the intent is to give guidance steps allowing supervisors some flexibility to manage conditions. Where available or required by permit specific instructions are listed in the tables. This is a living document; users of GSI Manual Volume V should feel empowered to provide written comment and new information to improve future updates.

1.3 Maintaining within Public View Seattle’s rights-of-way make up approximately 27 percent of all land area in the city. As such, right of way space is a valuable community resource that supports diverse mobility needs, community identity, civic activities, vital infrastructure, and critical environmental services. GSI facilities and associated elements should be maintained to align with these systems and provide multiple benefits. The first step in GSI maintenance is observation. O&M staff should physically

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observe GSI facilities during and immediately after storm events to gain an understanding of function, conditions and adjacent uses. Ideally this observation will occur in both wet and dry seasons. As GSI is a treatment that captures localized runoff, understanding the subtleties in grade, use and even aspect will contribute to successful long term performance.

This volume in concert with the other four GSI Manual volumes is intended to facilitate a consistent maintenance approach toward the successful function and public acceptance of GSI for stormwater management within the right-of-way.

1.4 Right-of-Way Context Figure 1 illustrates an example of a bioretention facility in the right-of-way.

Figure 1: Concept of Typical Bioretention in Street Right-of-Way Context

1.5 Coordination with O&M, GIS and Asset Management Staff during Design During the design phase the GSI project team will be reviewing and selecting the GSI tools, elements and/or components applicable to the project goals and location or context. These components are ones that have generally been reviewed and approved for citywide use in the

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right-of-way. Each project encounters some unique conditions or concerns so it is anticipated that a modification or new approach may be recommended for a particular condition.

In order to ensure the recommendations involve the O&M perspective the project design teams will submit to Agency O&M Staff the GSI Component Design Checklist for O&M concurrence with the applicable and new GSI tools.

1.6 Transition from Construction & Commissioning Period At the acceptance of construction, the following will have been completed for projects implementing GSI within the public right-of-way:

• Commissioning review • Record drawings filed and GIS updated • Project specific GSI technologies identified; location specific storm event protocols identified and included in project specific O&M manual insert • Establishment period sign off (period may vary by contract) • Public engagement activities notifying community that project is now under long term maintenance protocols • Identification of any special maintenance agreements, MOA’s, MOU’s, ADA special properties • Identification of potential maintenance partners • Regulatory agency approvals obtained • Other elements described in Volume IV of the GSI Manual.

1.7 Differentiating Operations, Maintenance and Annual Inspection For the purpose of this guidance operations, maintenance and annual inspection will be discussed separately however they are considered to be integrated in the terms of a functioning public GSI Asset Management Program.

1.8 GSI Construction Period Maintenance Maintenance during and immediately following construction is often part of the construction contract or handled as a specific work order. This type of maintenance often involves some tasks that may be considered “commissioning” as new facilities are integrated into the overall system. The maintenance protocols during this construction period are typically defined by the project team and may or may not respond to guidance included in this document. This period may also be used to allow soils to stabilize prior to the system to coming on-line and handling the stormwater. Agency staff will be informed when a facility is formally transitioned to O&M responsibility. See also Section 2.

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1.9 GSI Maintenance Guidance Tables

The purpose of the maintenance guidance tables (see Appendices A, B and C) is twofold; to provide an overview for Operations and Maintenance supervisors and to provide general guidance on tasks for field crews. The maintenance guidance tables cover when and what to inspect or observe in the field in order to determine staffing and task requirements. The tables include an overview of maintenance activities and timing for field crews. Provided for the maintenance crew are maintenance activities, typical frequency of the activities and definitions of acceptable and unacceptable performance standards. The acceptable performance standards are the targeted standards while the unacceptable performance standards indicate that maintenance, corrections or improvements are required to the GSI facility components.

Figure 2: Sample Page from the Routine Maintenance Guidance for Mature GSI in the Right-of-Way (Appendix A)

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The tables group the GSI Facility Components into categories such as “Facility Footprint”, “Inlets/Outlets/Pipe/Grates – Surface”, “Vegetation”, etc.

The maintenance guidance tables are:

1. Routine Maintenance Guidance for Mature GSI in the Right-of-Way (See Appendix A) 2. Establishment Period Maintenance Guidance for GSI in the Right-of-Way (See Appendix B) 3. Major Corrective Action and Long-Term Maintenance Guidance for GSI in the Right-of- Way (See Appendix C)

The Establishment Period Maintenance Guidance has the highest performance standards with higher frequency to allow the plantings to establish, minimize weed growth and check the designated inlet and discharge systems to monitor that they are handling the stormwater flows as anticipated. The Routine Maintenance Guidance includes the standard maintenance tasks that take place once the establishment period is completed. Finally, the Major Corrective Action and Long-Term Maintenance Guidance covers emergency conditions/extreme events, major repairs and infrequent, long-term maintenance activities.

1.10 Acceptable / Unacceptable Guidance Living systems are more difficult to classify as functioning or maintained as some aspects are subjective. Appendix D attempts to provide some visual guidance to the agency’s planned level of maintenance for more visible components or systems. Some tasks currently have placeholder “blanks” where suitable images are not readily available. This appendix should be updated periodically as facility maintenance experience grows and appropriate images are available.

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Section 2 Operations

2.1 Defining Parameters and Resources Green Stormwater Infrastructure is “young” in the context of utility operations and maintenance. As the systems are designed in context to local physical conditions and differing performance the supporting data on resource requirements for maintenance is limited. The understanding of what GSI elements are to be monitored for function is more understood than the staff time and material resources needed to maintain. This Section is a guide to GSI Operations and Maintenance from the perspective of public work infrastructure maintenance. It will be important to track and document activities so that more informed operations planning can occur. Tables and checklists included herein have been updated from recent maintenance discussions and it is anticipated that these will be updated periodically while the GSI program grows.

Note: the focus of the Operations content is bioretention however as with other sections of this volume there are placeholders for future content as other GSI elements and systems are planned for installation in the right-of-way.

The agency’s Team for Operation decisions may include the following:

SPU WTD Facility O&M Representative Project Delivery Branch Manager Capital Projects Planning & Delivery Unit Manager Lead GSI Engineer Lead GSI Landscape Architect Restoration Lead Agency Arborist or On-call arborist IT staff GIS staff Asset Management Lead Community Outreach and Communications Lead SPU Line of Business Representative (for SPU projects only)

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2.2 Contract Coordination for Commissioning GSI systems typically require a period of time to adjust and “settle in” to manage stormwater functions. There are three key steps:

a. Construction maintenance b. Warranty documentation c. Commissioning

2.2.1 Construction Maintenance GSI construction maintenance will be project specific depending on project scale and sequencing however the GSI installations require maintenance through acceptance as part of the construction process in order to minimize problems due to erosion, weeds and access. See below for establishment maintenance procurement options

2.2.2 Warranty Documentation This step involves the Contractor providing the Construction Contract lead with the documentation on final materials specifications, sources, warranties and system specific manufacturer information. GSI warranty documentation will be project specific depending on which elements or systems are employed.

2.2.3 Commissioning GSI commissioning for right-of-way bioretention should be tailored to the project. Operations staff are involved in commissioning as they want to know the facility they are going to manage functions appropriately. See Volume IV Construction and Commissioning. Commissioning generally involves:

• Gutter flow test to review the effectiveness of the curb inlets or pavement edge sheet flow in capturing the runoff • Flow test of the presettling cell to adjust placement of the concrete pad and adjacent boulders as applicable • Flow test for the weirs especially if they are used for flow control • Flow test for pipe inlets to be sure there is adequate flow dissipation to minimize erosion • Review of grades at the edges along walks to be sure there is positive sheet flow • Review at plants near curb inlets and weirs so they are placed for filtering but not blocking flow • There may be other elements to test depending on the specific facility design such as the set up and function of various UICs

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2.3 Contract Coordination for Construction Phase Establishment of Plantings GSI systems typically require a period of time for plantings to establish and soils to stabilize prior to allowing the system to come on-line and handle the stormwater. Decisions need to be made regarding:

a. Establishment time period b. Contract procurement approach c. O&M staff resources

Establishment is the term used for the period of time before a GSI facility is stable in plant growth and soils. For most plantings this is typically reached by three years; however a facility typically comes “on-line” or provides a stormwater management function prior to full establishment. Due to the need to bring on-line, it is critical that Operations staff be involved in the decision to determine the length of the construction phase establishment indicated in the PS&E contracts. The timing will vary according the planned construction season and completion date. For example a late spring completion might be open to receiving flow as early as six weeks but a late fall completion date could require waiting for several months prior to receiving stormwater flow.

It is also important for Operations staff to review design plans and construction contracts so they can forecast resource needs and the timing of the turnover to Operations staff for routine maintenance. If a facility is intended to be turned over to Operastions prior to three years then it will be important to address the resources required for establishment maintenance as this requires more labor hours and higher frequency. Generally the contract procurement options include:

• 3 months to 1 year for a typical GSI focused CIP contract • 3 months to 3 years for a larger CIP contract • Term based – maintenance focused work order contracts

2.4 Performance Standard As discussed in Section 1, GSI systems are required to be maintained to meet a performance standard. Establishment Period Maintenance, Routine Maintenance and Major Corrective Action and Long-Term Maintenance Guidance are detailed in Appendices A, B and C. The “Acceptable” rating for maintenance is set to meet the targeted standard for performance. Routine maintenance will keep facilities within this standard. Maintenance alerts will be triggered when a facility falls below this standard. Generally the reporting will be:

• Acceptable: “meets targeted standard performance” • Unacceptable: “corrections required” • Compliant: “meets regulatory requirements” • Complaint: “community comment”

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There may be discussion or comment on a “failed” system or component. As these are regulatory facilities a system considered failed means that the system is a candidate for major corrective action or extensive maintenance requiring authorized funding.

Due to the location of these facilities within the “public realm” there may be other non-regulatory maintenance requests that the O&M staff will be asked to address.

2.5 GIS Based Asset Tracking for GSI Facilities GSI BMP facilities include a range of technologies, components and materials. As the GSI program matures and these facilities become widespread, streamlining the tracking method within each agency’s asset management program will become routine. The specific GSI elements may require refined terms and titles in order to meet the various asset management and computerized tracking programs (e.g. Computerized Maintenance Management System – CMMS). The consistent use of terms is also important to spatially locate facilities using GIS database. While SPU uses “Maximo” and also tracks CSO efforts through CMOM (Capacity Management Operations and Maintenance); WTD tracks with SCADA. Furthermore SDOT uses the program “Hansen” and Seattle Parks uses “PLANT” for asset management. Future updates to this O&M manual should include a briefing of these various asset management software programs and how the GSI facilities will be included.

As discussed in Section 1 there will be coordination with the O&M team during design. The construction documents will coordinate with agency GIS staff to include the required facility tracking numbers or identification codes.

2.6 Regulatory Reporting; Agency Reporting and Updates Ecology requires annual inspections of all Stormwater Treatment and Flow Control BMPs/Facilities owned or operated by the Permittee (S5.C.9.c.i). This reporting includes:

• Bioretention facilities • UIC systems submittals per the specific UIC permit registration requirements.

For SPU-led projects: This reporting should include a feedback loop to update the Vol. II Options Analysis Phase and Vol. III Design Phase.

For WTD-led projects: This reporting should include a feedback loop to update the Vol. II Problem Definition Phase and Vol. III Design Phase.

See Appendix E for an example of a maintenance checklist.

2.7 Staffing The O&M team will include a variety of disciplines however the need for full time equivalents (FTE) will depend on the extent of facilities and types. The following are general categories for staffing in addition to operations management staff.

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Technical support:

• Field Engineer • Landscape Architect • Horticulturalist or Plant Ecologist • Arborist • GIS Tracking Specialist • Community Relations Lead/Public Engagement Specialist • Post Construction Monitoring - Instrumentation and Control staff

Field support:

• Supervisors • Gardeners (recommend teams of 3 to 5) • Equipment Operators

Specialized or Outsourced support:

• Vactor Truck Crew • Pipe Cleaning and Inspection • Well Maintenance and Repair Crews (Deep Infiltration) • Signage Repairs (SDOT approved list xx) • Arborist (qualifications per SDOT Street Tree Manual Director’s Rule 3-2014)

Resource staff:

• Civil Engineer(s) for assistance with corrective actions that may impact regulatory function. • Landscape Architects for (for GSI and street improvements field adjustments, and analysis) • Geotechnical Engineer/Geologist/Hydrogeologist • Structural Engineer (e.g. vertical wall designs) • Permit Specialist • Procurement Specialist for seasonal support, work order or material contracts

2.8 Training GSI systems are relatively new to the field of public works maintenance and as such it is recommended to define a base level of skills and a training regime to support the expanding GSI program in the context of the regulatory requirements. While it is often noted that landscape maintenance skills support GSI requirements there are distinctions in approach that require training or orientation. As these are public facilities meeting a prescribed function the field crews should be trained in this regard. Currently the program sponsored by the Washington Association of Landscape professionals (WALP) ecoPRO Certified Sustainable Landscape Professional Program may be the most well rounded training for maintenance staff however agency specific GSI training will still be required.

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(see https://www.mediafire.com/folder/bhtkl2b5iq7mu/Sustainable_Landscape_Professional_Cert)

2.9 Equipment GSI systems have specialized materials and design elements that may require a review of the agency’s readily available equipment resources. The operations management staff should receive the project specific design elements checklist at turnover in order to confirm that suitable equipment is available for maintenance and inspection.

Typical Equipment includes:

• Crew specific needs such as reflective clothing, gloves, boots, etc. • Routine landscape maintenance tools such as shovels, brooms, pruners, etc. • Soil monitors such as soil moisture sensors, T-handle core sampler; soil auger and infiltration testing equipment • Watering equipment (see facility design or GIS tracking for automatic irrigation system) • Small pipe inspection/maintenance tools for the underdrains • Storm drain maintenance equipment for MH structures, CB’s and inlet/outlet pipes • Specialized equipment such as blowers (use should be carefully reviewed i.e.- blow off permeable pavements do not blow out bioretention areas)

Large Equipment /Outsource requirements typically include:

• Trucks • Small excavator • Sweepers (vacuum based preferred ) • Industrial shop vacs • Vactor truck • CCTV/Electromagnetic/Ultrasonic pipe inspection • Specialized equipment for UIC maintenance

2.10 Materials GSI systems have specialized materials and design elements that may require a review of the agency’s readily available maintenance material supplies and equipment resources. Typically for bioretention these materials include:

• Bioretention Soil Mix per COS Section 9-14.1(3) unless location notes a special mix. • Mineral Aggregate COS Section 9-03.2(2) with exception of the passing for sieve #200 shall be one to three percent. • Fine compost shall conform to COS Section 9-14.4(9). • Bioretention Minor Soil Replacement Mix (for areas smaller than two cubic feet of material), the following mix of materials that are available at a local hardware store can be mixed well and used for areas requiring less than two cubic feet of material:

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o 2 bags of pea gravel (1 cubic foot) o 2 bags of play sand (12 cubic foot) o 1 bag of Cedar Grove compost (one cubic foot) Cedar Grove’s Bioretention Soil Mix may also be used for minor repairs.

• Mulch for Top Dressing o Arborist Wood Chip Mulch - COS Section 9.14.4(5) – with the exception that it shall not be longer than 4-inches and shall not be derived from recycled lumber. o 50/50 Mix of Coarse Bark Mulch and Arborist Wood Chip Mulch • Culvert Geotextile Fabric shall conform to Mirafi 140N, US Fabrics US 120 NW, or an approved equivalent product. • Compost Sock, Coir Log, Wattle shall conform to Ecology’s 2005 Best Management Practices (BMP) C235 and COS Section 9-14.16/WSDOT Section 9-14.5(5). • See COS standard specifications and project specific plans and specifications for replacement materials not shown.

2.11 Pavement Surfacing Materials for Repair/Replacement GSI systems often have hardsurface elements such as those listed below. When sourcing replacements, the materials shall meet the project plans specifications or COS Standard Plans and Specifications.

• Pavers • Precast concrete pad: Replace to match or refer to project plans for replacement pad specifications • Permeable concrete pavement: Refer to COS GSI repair guidance for permeable concrete paths major repairs • Porous asphalt: Project specifications • Curbs and curb inlet: Project plans and specifications • Standard concrete walks: COS standard plans and specifications

2.12 Plant Replacement Materials GSI systems have specifically selected plant materials - See Appendix G for approved GSI Plant Lists. When sourcing replacements the plant materials shall meet the requirements in Table 2-1 below.

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Table 2-1: Plant Material Requirements & Considerations Plant Materials Requirements & Considerations • Plants to be nursery grown in climatic conditions similar to Seattle. • Measurements, caliper, branching, grading, quality, balling and burlapping are to follow Code of Standards of American Plant Stock Association of Nurserymen in the most current American Standard for Nursery Stock unless otherwise specified. • See Project Plans for specific plants substituting a plant with another species or variety match height and growth pattern of original plant for right-of-way use. • Trees to have an overall form typical of the species, uniformly branched, with a symmetrical crown. • Trees with curved or leaning trunks, damaged leaders, uneven canopies, damaged bark, sunscalds, disfiguring knots or fresh Form cut limbs over 3/4" will be rejected. • Coniferous trees to be in native form (not sheared) with a single dominant leader. • Shrubs to have an overall form typical of the species, uniformly branched, with a symmetrical crown. Bare Root Trees and • Bare root plants are acceptable within the late fall to early Shrubs spring season. • Plants to have been grown in container for sufficient length of time for the root system to have developed to hold its soil Container Grown together, firm and whole. • No plants shall be loose in the container. • Container stock shall not be pot bound. • Plants to have firm, natural balls of soil, wrapped firmly with Balled and Burlapped burlap or approved material, and bound carefully with twine, cord or wire mesh. • Grasses and emergents may be available in a variety of forms. Typically it is best to plant small (<1 gallon) containers or 5 to Grasses and 10 cubic inch plugs. Bare root plugs are acceptable if they are Emergents well-rooted and watered by an automatic irrigation system. • It may be an option to divide a larger grass container into two or three plants.

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2.13 Other Materials Required during Plant Replacement When replacing plants other materials are often required. When sourcing replacements the materials shall meet the following requirements listed in Table 2-2 below.

Table 2-2: Other Planting Component Requirements & Considerations Planting Requirements & Considerations Components • Compost and arborist wood chip mulch that is applied semi-annually provides the fertilizer required for the system. • Tree fertilizers shall contain all natural ingredients. Fertilizer and Soil • Fertilizer product to be approved by an ISA certified arborist. Amendments • Approved products may include: o Plant Health Care, MycorTree Injectable o Plant Health Care (PHC) for Trees (select specific blend based on tree health, soil testing and location) o Humic acid • Tree tie shall conform to COS Section 9-14.7. Tree Staking • Wood stakes shall be 2-inch by 2-inch by 8-foot long Lodgepole pine wood stakes. • See Appendix I, Draft King County Integrated Pest Management Document. Herbicides • Follow the recommendations of herbicide use within Class B streamside buffers (waterways). • See Appendix I, Draft King County Integrated Pest Management Document. Pesticides • Follow the recommendations of pesticide use within Class B streamside buffers (waterways). Irrigation • See project specific record drawings and manual. • 3-inch minimum to 6-inch maximum well-graded washed rounded Cobbles cobblestone rock or an approved equivalent product. Cobbles shall not be procured from natural stream bed channels. • Pipe protection boulders shall be of a similar color and type in accordance with the size noted on the plans. • Weir boulders shall be in accordance with the size noted on the plans Boulders and COS Section 9-03.17. • Boulders shall be High Cascade Granite smooth finish, free of cracking and flaking.

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2.14 GSI Facility Component Corrective Actions First it is important to confirm that the facility in question is part of the agency’s specific compliance with their NPDES permit, either installed to bring the system into compliance (e.g. retrofit ) or installed as part of development code compliance (e.g. new development). A voluntary installation such as neighborhood roadside rain gardens is not likely part of the compliance. If a voluntary system is failing and requires major repairs the agency may choose to take it offline and return the area to standard right-of-way treatment. (See below)

If a code required GSI facility component is not properly functioning and is in need of major corrective action, operations supervisors are to work with agency technical staff to determine if the component or portion of the system is repairable. As each individual facility (e.g. cell, UIC, drilled drain, etc.) contributes to the agency’s NPDES permit compliance, coordinating major repair, replacement or other approach requires the involvement of the agency’s compliance staff. Depending on the decision consultation with ECY may be required.

If a major repair is required and the facility will be offline then accommodation will be required to maintain the compliance threshold for that basin. This will require location specific analysis.

Triggers for failure may include:

• The component or asset no longer meets its design objectives, requires major repair and is not needed to meet the design capacity. Examples piped inlet is crushed; upstream conditions have changed so flow is redirected; drilled drain plugged; UIC well contaminated, etc. • Ponded water that is not corrected through routine maintenance (standard operating procedures). • Vegetation growth exceeds typical maintenance and requires full replacement. • Major storm has caused tree failure, compromising underground system components. • Reports of visible water on adjacent properties requiring investigation of underdrain and liner.

Issues to consider prior to taking a code required facility offline for a temporary period may include:

• Review season options - can the work be delayed to the dry season? • Review options for temporary treatment. • Is there a downstream facility in the same basin that can be adjusted to temporarily address the flow and water quality needs? • Can the component or system be taken offline while kept in place? For example, a bioretention cell that does not drain could be filled with soil to the gutter line, creating a flow-in / flow-out cell. If the cell is located in a series of cells, this would maintain the general aesthetics once the cell is replanted. If the cell is isolated and surrounded by

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lawn, an option might be to fill the cell with soil, fill in the curb cut inlets, and restore to lawn. • If the cell is lined what is a reasonable period of time before the area becomes anaerobic due to saturation from direct rainfall?

Major corrective maintenance actions that require taking a cell or facility offline for more than 14 days in the dry season and more than three days in the wet season will require a specific work plan to be approved prior to start of work.

2.15 Removal of Voluntary GSI Facilities • Notify the neighborhood group or owner that the facility is noted as failed and corrective active or removal is required. • The first choice would be to review if an adaptive management approach would allow some continued stormwater function. For example if it is an unlined system, would it be suitable to reqrade to a few inches below gutter line and allow a shallow flow in/flow out conveyance treatment to occur in place of full bioretention? If the “failed” cell is located in a series of cells, this approach would maintain the general aesthetics once the cell is replanted. If the cell is isolated and surrounded by lawn, an option might be to fill the cell with soil, fill in the curb cut inlets, and restore to lawn. • If facility is tagged for removal then GSI operations staff should refer back to the ROW use agreements and the responsible party notified that removal and restoration is required per terms of the agreement. If the failed condition is ponded water then O&M staff should block the curb cuts and inlet pipes as applicable to minimize impacts of standing water such as anaerobic conditions and mosquito habitat.

2.16 Coordination with Other Right-of-Way Uses, Policies and Programs In addition, to ensure coordination of maintenance with other right-of-way infrastructure, uses of the ROW, and adjacent parcel improvements the use of GIS for locating facilities and tracking maintenance is strongly recommended. Finally O&M staff should maintain awareness of city policies and programs such as:

Special Routes

• KC Metro Transit Routes • Fire/Emergency Vehicle Routes on Residential Streets (check with local fire station) • School Bus Routes • Safe Routes To School • SPU Recycling/Garbage/Yard Waste Management Route Maps

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Programs

• Safe Routes To School • RainWise Program • reLeaf Program • Utility infrastructure improvements (franchise, Seattle City Light, Water, Sewer, etc.) • Other capital improvement projects planned for GSI facilities area • Other City/Community plans and activities

Plans

• Pedestrian Master Plan Implementation • SDOT Street Tree Manual • SDOT Trees and Sidewalks Operation Plan • Bicycle Master Plan Implementation • Neighborhood Greenways Implementation • Transit Master Plan • Urban Forest Stewardship Plan • Freight Master Plan • Franchise Repairs and Improvements

2.17 Emergency Management: Response For SPU-led: refer to City if Seattle Emergency Operations Center.

SPU 24-hour emergency (206) 386-1800.

For WTD-led: refer to King County’s Comprehensive Emergency Management Plan

WTD’s 24-hour emergency service line (206) 263-3801.

See also Section 8: Storm Events, Extreme Weather or Emergency Maintenance

2.18 Update Risk Management A yearly reporting of issues that affect risk management should be prepared and submitted to respective agencies. This report may include observed conditions such as storm event resilient design features or recommendations, physical conditions related to specific locations or land use and other problematic issues or observance. This reporting should provide a feedback loop to update the Vol. II SPU’s Options Analysis/WTD’s Problem Definition Phase and Vol. III Design Phase.

Finally this report should include documentation if a facility has been determined as requiring major corrective action. (See Appendix C)

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2.19 Feedback Loop to Update GSI Manual For SPU-led projects reporting to include a feedback loop to update the Vol. II Options Analysis and Vol. III Design as well as this Vol. V Operation & Maintenance.

For WTD-led projects reporting to include a feedback loop to update the Vol. II Problem Definition Phase and Vol. III Design Phase as well as this Vol. V Operation & Maintenance..

2.20 Public Information See Section 10 of this Volume.

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Section 3 Maintenance of Bioretention Surface Facilities

3.1 Overview The GSI facilities implemented in the right-of-way are considered living systems that adapt over time to specific conditions and are subject to weather patterns. Consistent maintenance is essential to ensure that the systems are efficient, long lasting and the prescribed performance for the BMP’s are being achieved. This manual discusses routine performance and timing of procedures. It outlines this procedure through the Maintenance Guidance Tables in Appendices A, B and C. A list of resources (See Appendix K) is included for additional information.

Surface facilities are considered to include the following: facility footprint, soils, dams, weirs, inlets/outlet pipes, curb inlets, grates, vegetation, mulch, and hardscape. Depending on the specific facility some elements may or may not be considered part of the GSI maintenance however excluded elements should be documented in the agency’s asset management tracking and/or CMMS.

Maintenance limits should also be indicated by the facility tracking number. Generally the maintenance area includes the area between curb and sidewalk and longitudinally from cell to cell. If deep infiltration components are included in the facility then the maintenance area may extend further depending on the surface treatment. Finally if the facility is intercepting flow from upstream there may be an upstream catch basin or inlet that is included in the facility. (See Section 2 Operations for GIS information).

Note: the focus of this content is currently bioretention however as with other sections of this volume there are placeholders for future content as other GSI strategies, components, elements and systems are planned for installation in the right-of-way.

3.2 Establishment Period The establishment period is an important time for GSI implementation and function. During this period it is important to observe how the facility is performing both in terms of function and aesthetics. Construction completion may be considered the end of installation however construction contract acceptance is generally through a procurement contract defined establishment period.

3.2.1 Construction Establishment – typically 3 months to 1 year Construction contracts will vary in the time allocated for establishment. This variance is due to several factors such as funding, construction season, project specific design elements and staffing. Typically construction establishment is not less than three months as this is the

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period of time that the facility is being observed and commissioning occurs. The bottom area and lower slopes should have roughly 75% plant coverage however most importantly plants should be visibly thriving. The facility should be weed free, sediment removed and no eroded channels at time of turnover. Trees should be thriving and leaders straight with visible sign of growth. Low tree branches (under four feet) should be pruned. See Section 7 for additional information on contracting for establishment.

A stand alone permeable pavement facility may have a limited establishment period as the primary need is to ensure that the edge conditions have been restored to minimize erosion of sediment onto the surface.`

3.2.2 Establishment Period – 1 year to 3 years The first three years of any vegetation is a ‘test period” for trees and plants. The time from construction completion turnover to facility establishment is typically a two to three year duration for bioretention facilities. During this period the facilities will be maintained to a higher level with two objectives 1) maintaining an environment to allow the plantings to mature to full coverage and 2) minimizing weed infestation. During this establishment period it is recommended to schedule a higher frequency of maintenance. The plants should be thriving; the facility should be weed free, sediment removed and no eroded channels at time of turnover. (See Appendix B – Establishment Period Maintenance Guidance for GSI in the Right-of-Way)

3.2.3 Establishment Transition to Routine Maintenance During the third year of establishment it is important to review conditions and make adjustments to elements that may be causing higher than normal maintenance. These may include curb drain slope, cobbles, presettling may be too large or too small, a grate may need to be replaced or a problem plant removed. The intent is to identify facility adaptations in order to shift from the higher frequency inspection and maintenance to a routine schedule. (See Appendix B)

3.3 Maintenance for Established Facilities 3.3.1 Routine Maintenance The Routine Maintenance Guidance Table (See Appendix A) outlines maintenance tasks and procedures that occur throughout the year.

3.3.2 Major Corrective Action and Long-Term Maintenance The Major Corrective Actions and Long-Term Maintenance Guidance Table (Appendix C) outlines procedures when more difficult, timely or costly task are required.

3.4 Maintenance for Specific Components within Facility The Table below provides a general example of components with the facility footprint. See Appendix A, B and C.

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Table 3-1: Component Examples Component Description Facility Footprint • Soils, check dams, weirs, vertical walls, extents. • Grates, trash racks, drain curb cuts, presettling cells, Inlet/Outlets/Pipes – Surface direct connection catch basins, inlet pipes, outlet pipes. Inlet/Outlets/Pipes – • Maintenance holes, catch basins, inlets, underdrains, Subsurface liners, storm drains, and service drains. • Cell bottom, cell slope, step out zone, crossings, Vegetation intersections zones, trees and other. Mulch • Compost, arborist wood chip, coarse bark and other. • Hand or truck watering, quick couplers and automated Watering irrigation. • Underground injection control, upstream maintenance Deep Infiltration (over 6 feet ) holes, pit drains, drilled drains and other. • Pavements in streets and alleys that perform for GSI Permeable Pavement Facility management function including underdrains and check dams. • Special surface treatment on streets, sidewalks, curb Hardscape edge cells, paved crossings, step out zones, facility related traffic control signage. • A facility may include specialty elements such as interpretive signage, street furnishings such as benches, trash cans or mutt mitts stations or public Specialty Elements art. These elements should be reflected for specific maintenance requirements within the project specific O&M Asset Management list and the CMMS.

3.5 Future placeholder.

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Section 4 Maintenance of Structures and Subsurface

Storm Drainage

4.1 Overview The GSI facilities implemented in the right-of-way are considered living systems however these systems are engineered to meet the performance required by Ecology for the prescribed BMP’s. This manual discusses and outlines routine inspection, maintenance tasks, timing of procedures and performance. (See Appendices A, B and C). A list of resources (See Appendix J) is included for additional information.

Structures and subsurface facilities are considered to include the following: vertical walls, catch basins, maintenance holes, inlets, subsurface trench dams, liners, underdrains, clean outs and observation ports. Depending on the specific facility some elements may or may not be considered part of the GSI maintenance however this should be documented in the agency’s asset management and/or CMMS.

Note: the focus of the content is bioretention however as with other sections of this volume there are placeholders for future content as other GSI strategies and elements are planned for installation in the right-of-way. xxxx.

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Section 5 Maintenance of Deep Infiltration Infrastructure

Placeholder

5.1 Overview When soils have low infiltration rates in areas that are otherwise suited for GSI solutions then the location may include other means to keep stormwater out of the piped system. These methods are grouped under the category of deep infiltration. The methods include underground injection control (UIC) wells, pit drains, drilled drains, screen wells and others similar in approach. All deep infiltration will eventually require maintenance or rehabilitation, regardless of construction methods or materials used. This time span depends upon many factors including water quality, aquifer characteristics, design and materials, installation procedures, inflow rates and as applicable equipment quality. Maintenance of deep infiltration will require the participation of a variety of persons depending on the facility including field inspectors, contractors, licensed well drillers and licensed hydrogeologists and/or professional engineers.

Note: the focus of the content is bioretention however as with other sections of this volume the sections below are placeholders for future content as other GSI strategies and elements are planned for installation in the right-of-way. There is ongoing discussion about the level of maintenance and monitoring of these deep infiltration systems. See Appendices A, B & C for examples of project specifc O&M guidance. There are also questions as to the level of sediment that will clog these systems. Early UIC well installations will be monitored and documented so it is expected that following a year or two of maintenance the guidance, methodology and protocols will be refined to develop overall standards.

5.2 Underground Injection Control Wells for Stormwater UIC wells may be used for discharging treated stormwater when it is designed to meet Ecology’s requirements in accordance with their publication number 05-10-067 titled “Guidance for UIC Wells that Manage Stormwater.” 'UIC' is a term used by Ecology (see page 2 of the Guidance for UIC Wells publication) to describe a “manmade subsurface fluid distribution system design to discharge fluids into the ground and consists of an assemblage of perforated pipes, drain tiles, or other similar mechanisms, or a dug hole that is deeper than the largest surface dimension (Washington Administrative Code 173-218-030).” A UIC well will extend past the underlying till soils and discharge treated stormwater runoff via a slotted/screen pipe located in advance outwash soils that have been determined to be suitable for infiltration. The permitting and registering of UICs is through Department of Ecology.

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There are different types of UIC wells pipe with a screen (e.g. “screen well”) or media backfilled (such as pit drain or drilled drain) etc). The design of the UIC well (depth, type of well, screen length, diameter of borehole etc) is project-specific in coordination with the civil engineer, geotechnical engineer/hydrogeologist and O&M representative of the Project Team. Due to this project specific approach the maintenance protocols need to be tailored or noted for each particular type.

5.3 Screen Wells This section is a placeholder.

A screen well deep infiltration facility is typically used to reach suitable soils that are deep below the surface up to 100-foot depth (at a depth greater than a drilled drain). A large drill rig is used for construction of screen wells. Boring diameter for a screen well can vary (i.e. 6 to 12-inch) with 6 to 8-inch well casing. Sizing and design of the casing and screen is project specific factoring in both infiltration rate of the native soils and maintenance access for observation ports, conveyance pipes etc. The design (depth, casing length, design infiltration rate, diameter of borehole, screen size and length, conveyance pipe, observation port, maintenance access structure, etc) and siting of the screen well is project-specific in coordination with the civil engineer, geotechnical engineer/hydrogeologist, landscape architect and O&M representative of the Project Team. A maintenance hole is located over the screen well for maintenance access to the well.

See Appendix G for the UIC Maintenance Requirements for the screen wells that were installed for WTD’s Barton CSO Control project with GSI.

Maintenance protocols based on WTD’s Barton CSO control project are included in the Maintenance Guidance Tables in Appendices A, B and C. However, because of the limited implementation thus far they are a placeholder.

5.4 Drilled Drains This section is a placeholder. See Appendices A, B and C for Project Specific O&M Guidance.

Drilled drains (media-backfilled UIC wells), may be used for discharging treated stormwater, provided the drain is designed to meet Ecology’s requirements as specified in the “Underground Injection Control Wells for Stormwater” section, above. These drains are constructed by drilling through low-permeability surface soils to access underlying unsaturated, permeable soils suitable for infiltration. The upper section of the boring (characterized by low-permeability soils), is sealed off with casing pipe to limit the migration of fines from the surrounding soil into the drain. The boring is then backfilled with a permeable media to provide a conduit for treated stormwater runoff into the permeable soils.

These drains are shallower than screened UIC wells, typically ranging in depth from 50 to 80 feet. They also have a larger diameter shaft than screened UIC wells, typically 24 to 36 inches,

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compared to typical screened UIC wells comprised of six to eight-inch diameter screen and casing pipe. The design of the drilled drain (depth, casing length, diameter of borehole, etc.) is project-specific and designed in coordination with the civil engineer, geotechnical engineer/hydrogeologist and O&M representative of the Project Team. Depending on site conditions and the project-specific design, the drilled drain may also include components such as a slotted vertical conveyance pipe in the boring, sand filtration layers at the surface of the drain, and/or an access structure at the surface to provide maintenance access and protect the drain.

Maintenance protocols will be added as projects using drilled drains are completed. See Maintenance Guidance Tables in Appendices A, B and C.

5.5 Pit Drains Pit drains may be used for discharging treated stormwater when there is a thin layer of till near the surface in order to tap into advance outwash soils that are more suitable for infiltrating and the suitable soil is accessible within the reach of excavator. Pit drains are typically not considered UIC wells because the depth of the facility is usually less than the largest surface dimension (See Ecology publication 05-10-067 for UIC wells). The pit drain is a trench that is excavated up to a 15-foot depth and backfilled with free-draining material. Pit drains may be installed directly below each bioretention cell, thus not requiring an underdrain pipe; or they may receive filtered stormwater from a series of bioretention cells with an underdrain pipe. Note: these facilities should be named so that they can be identified in the CMMS such as Maximo.

Maintenance protocols will be added as projects using pit drains are completed. See Maintenance Guidance Tables in Appendices A, B and C.

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Section 6 Maintenance of Permeable Pavements

6.1 Overview This section describes the guidance for maintenance of permeable pavement systems in the right-of-way for sidewalks, neighborhood streets and alleys between neighborhood streets. Permeable pavement is a paving system that allows rainfall to percolate through the surface and into the underlying soil. The two guiding operations and maintenance principles for ensuring long term performance of a permeable pavement system are: drainage function and structural condition. The routine, establishment and major corrective action maintenance activities described in Appendices A, B and C are based on ensuring that these perform over the long term.

Currently, pervious concrete is the only approved permeable pavement material for public sidewalks and full neighborhood public alley applications that are maintained by City. See Design Volume for further information about use in the ROW. This section is placeholder since City design standards and guidance for pervious concrete is currently under development in coordination with SDOT.

6.2 Components of Permeable Pavement System The components of a permeable pavement system depend upon the design of the pavement section. The main components are:

• Wearing Course (surface layer of pervious concrete, porous asphalt or permeable interlocking pavers) • Subbase material (for structural support and/or storage of rainwater as it infiltrates)

Other secondary components that may or may not apply to a pavement section include:

• Geotextile • Subsurface Check Dams • Utility Trench Dams • Underdrains/Elevated Subsurface Overflow Pipe

Review record drawings and city asset tracking systems for components at a specific location.

6.3 Sidewalks Maintenance of pervious concrete sidewalks is described in the guidance tables (routine, establishment, corrective action/long-term) in Appendices A, B, and C.

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6.4 Pervious Concrete Neighborhood Streets/Alleys Maintenance of pervious concrete neighborhood streets and neighborhood alleys are described in the guidance tables (routine, establishment, corrective action/long-term) in Appendices A, B, and C.

6.5 Future This section is a placeholder.

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Section 7 Outsourced and Stewardship Maintenance

7.1 Overview Ecology requires LID BMP maintenance of all permanent Stormwater Treatment and Flow Control BMPs/Facilities that are regulated by the Permittee (S5.C.9.b.i)

7.2 Outsourced and/or Work Order Contracts See Appendix F for example of a GSI Maintenance Work Order Specification.

7.3 Stewardship See Appendix K for Roadside Bioretention Cell Care Guide.

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Section 8 Storm Events, Extreme Weather or Emergency

Maintenance

8.1 Storm Events Regulatory:

Ecology requires spot checks of potentially damaged permanent Stormwater Treatment and Flow Control BMPs/Facilities after major storm events (more than 1-inch rain in 24 hours or wind above 20 mph). If spot checks indicate widespread damage/maintenance needs, inspect all Stormwater Treatment and Flow Control BMPs/Facilities that may be affected (S5.C.9.c.ii). Conduct spot repairs or perform maintenance in accordance with the maintenance guidance tables (See Appendices A, B and C).

Practical:

Large storm events require special attention for GSI facilities. These are defined as 1/2-inch or more rainfall in 24 hours.

• Curb cuts • Catch basins • Weirs • Street surface • Vegetation

8.2 Extreme Weather 8.2.1 Temperature GSI systems are living systems and as such they are subject to impacts due to extreme heat and cold.

• In extreme heat such as temperature over 90 degrees F for over a period of one week it is recommend that the bottom zone of established bioretention be watered deeply (+/-2inch depth) once a week to minimize 100% die off and resultant loss of function. • In extreme cold such as temperature below 12 degrees F for over a period of three days or a deep snow of more than 12 inches followed by an erratic warming freezing cycle, it is recommended that surface features such as sediment bays, weirs, inlets

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and catch basins be reviewed for damage and repaired as needed per Appendix C or Agency standards for structures.

8.2.2 Wind GSI systems are typically not directly affected by wind however high winds may result in debris clogging inlets and potential for tree damage.

8.3 Spills • SPU staff and Contractors shall be trained to recognize, prevent and clean up hazardous waste, excessive oil, spills and sediment. The following web site has contains useful information regarding spill response: http://www.seattle.gov/util/MyServices/DrainageSewer/PollutionControl/index.htm

• WTD staff and Contractors shall be trained to recognize, prevent and clean up hazardous waste, excessive oil, spills and sediment. Follow Specification 01560 Environmental Management for spill prevention and response. The following web site has contains useful information in developing a spill plan: http://www.kingcounty.gov/healthservices/health/ehs/toxic/HazSpills.aspx

8.4 Vandalism Acts of vandalism may occur and might range from minor tree limb damage, plant removals, cobble displacement to more extensive damage such as concrete curbs broken or walls damaged. These situations should be reported to the Operations Manager so they can track trouble spots and assess if further investigation is warranted. If possible field staff should photograph conditions.

If vandalism involves large waste deposits (more than 3 cubic feet (extra large bag) within a bioretention cell or the material is hazardous, notify O&M manager immediately for direction..

8.5 Vehicular Damage In the event it is observed that a vehicle has damaged a facility edge or gone into the facility, field staff should evaluate surface conditions, take phtos and submit a request for further investigation of potential damage. As each facility may have differing underground elements such as liners, pipes or soil depth a more detailed review may be required to ascertain damage.

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Section 9

Inspection

9.1 Overview Inspections, tracking of maintenance activities and reporting for regulatory compliance is dependent upon if the GSI facilities was installed for MS4 (NPDES permit) or addressing combined sewer overflows. Contact each agency’s compliance staff for inspection and regulatory reporting requirements.

For WTD facilties contact WTD’s Maintenance section’s West Section Manager. For SPU facilities, contact SPU’s regulatory compliance point of contact.

9.2 Regulatory This section is a placeholder.

The regulatory requirements for gsi facilities will vary based on what the purpose was for the installation and the elements of the GSI facility (e.g. retrofit for CSO control vs MS4 permit /stormwater code).

 xxx

Ecology requires annual inspections of all Stormwater Treatment and Flow Control BMPs/Facilities owned or operated by the Permittee (NPDES permit S5.C.9.c.i).

9.3 Record Keeping This section is a placeholder.

Maintain records of maintenance activities and inspections for the asset in accordance with regulatory requirements. See each agency’s compliance staff for requirements.

9.4 Asset Management This section is a placeholder.

 xxxx

9.5 Complaint-Based This section is a placeholder.

 xxx

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9.6 Role of Inspector This section is a placeholder.

 Internal staff  Street Improvement Projects - 3rd party inspection (outsourced)

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Section 10 Public Engagement

10.1 Purpose and Objective The Public outreach effort that began during the Options Analysis/Problem Definition phase and then through Design and Construction & Commissioning phases will be the basis for ongoing effort to help establish trust and transparency in the maintenance for GSI function.

During Operations and Maintenance:

Public engagement goals are to:

• Demonstrate to neighbors that SPU and WTD remain invested in the project beyond construction.

• Encourage neighbors to stay engaged and invested in the project.

• Ensure the project remains an enduring and successful example of GSI so other neighborhoods will get excited about the possibility of having a similar project in their community.

Public engagement objectives are to:

• Update the public engagement plan (PEP).

• Clarify SPU/WTD’s roles and responsibilities for maintaining the project, and manage neighbors’ expectations for maintenance levels.

• Transition public engagement responsibilities to the O&M team.

• Encourage neighbors—including historically-underserved and limited-English proficient residents and renters—to take interest in and responsibility for the project.

• Create opportunities for neighbors to showcase their project, such as posting images online and holding GSI tours.

• Keep neighbors informed of any potentially disruptive maintenance activities by providing advance notifications with information about what to expect.

Community input received to date and new project information will inform the Public Engagement Plan (PEP) update for O&M. The updated public engagement plan should provide strategies to address community issues and activities to support ongoing work.

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10.2 Outreach Tools The PEP update will be relatively short. The SPU/WTD community relations lead will plan and implement all outreach tools in coordination with the Project Team. Outreach tools will be aligned to share information and/or gather comments about activities or changes that may occur over time. Specific outreach tools may include, but are not limited to, items identified in Table 10-1:

Table 10-1: O&M Outreach Tools

Project milestone Potential outreach tools Purpose of outreach End of construction • Ribbon cutting celebration event • Manage expectations for • Project website maintenance • Maintenance schedule handout • Clarify roles and responsibilities • Maintenance service level for maintenance handout • Encourage ongoing community • Public meeting/open house engagement and investment in • Interpreter/translation as needed project

Prior to disruptive • Listserv announcement • Keep neighbors informed of maintenance • Website update maintenance activities that may activities • Flyer distribution cause disruption • Posters • One-on-one communication • Project communication log • Door-to-door (for highly disruptive activities) • Interpreter/translation as needed

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Periodically • Website • Give neighbors a chance to • GSI in-person and virtual (video, showcase their project to online) tours others • Interpretative signage • Sustain ongoing pride in project • Generate excitement in other neighborhoods about GSI opportunities

10.3 Work Plan Table 10-2 outlines a draft work plan for the operations and maintenance.

Table 10-2: Work Plan Draft Outline Task Participants Approximate Duration

Update PEP • SPU/WTD community relations Two weeks lead • O&M team

Confirm ongoing • SPU/ WTD community relations One month communications infrastructure lead (e.g. website, maintenance hotline, listserv)

Plan outreach activities • SPU/ WTD community relations Ongoing lead • O&M team

Implement outreach activities • O&M team Ongoing

Draft public engagement • O&M team Annual report

10.4 Training and Handoff Operations and Maintenance represents a project milestone when public engagement responsibilities transition from the SPU/WTD community relations lead to the O&M team. To support that transition, the SPU/WTD community relations lead will update the PEP and train the O&M team. Training will focus on project background, including unique characteristics of the

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Updated July 2015 GSI Manual: Volume V – Operations & Maintenance

neighborhood that are relevant to public engagement and existing communications tools, such as the project hotline.

10.5 Reporting SPU’s or WTD’s O&M team will provide ongoing documentation of all outreach activities and public comments on an annual basis. The O&M team may summarize the results of the outreach for feedback to future project design and maintenance processes.

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Updated July 2015 GSI Manual: Volume V – Operations & Maintenance

Section 11 Voluntary Installations - Future

11.1 Overview SPU and WTD are active in partnering with xxxxx.

11.2 Tracking Xxxxx

11.3 Inspection

11-1

Updated July 2015 GSI Manual: Volume V – Operations & Maintenance

Section 12 Maintenance Agreements and Related Policies-

Future

12.1 Overview SPU and WTD are active in partnering with xxxxx.

12-1

Updated July 2015

GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix A: Routine Maintenance Guidance for Mature GSI in the Right-of-Way

GSI Manual, Volume V – Operations & Maintenance Appendix

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SPU/WTD GSI Program Management SPU #C12-004 Date: July 2015 SvR #12034

ROUTINE MAINTENANCE GUIDANCE FOR MATURE GSI IN THE RIGHT-OF-WAY Notes: 1. The following table is based on the "Guidance Document: Western Washington Low Impact Development (LID) Operation and Maintenance (O&M)" prepared for Ecology Water Quality Program - July 8, 2013 and the 2014 update to City of Seattle's Stormwater Manual. 2. Timing is guidance and may be adjusted to site specific conditions. 3. See Examples: Acceptable / Unacceptable Guidance in the appendix of GSI Manual, Volume V. 4. See separate tables for specific guidance for establishment and major corrective action / long-term maintenance. (Mature = established, generally 3+/- years) 5. Bold Text = High priority for function or safety 6 Orange indicates topic areas that are under development, the guidance included is a placeholder. Refer to project specific O&M guidance in the interim.

OPERATIONS-SUPERVISOR MAINTENANCE-CREW PERFORMANCE STANDARD ADDITIONAL INFO Frequency (Schedule for Full Review 5X GSI Facility Observation Month Unacceptable Comments per year. Jan. March. June. Acceptable Component (Walk facility-look for conditions that Maintenance Activity (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Sept. Nov.; below are may trigger maintenance activity) (Targeted Standard) Required) specialized visits that may be concurrent) Major Storm Events (more than 1" rain in 24 hours or wind above 20 mph)

□ Remove at a minimum blockages/leaves from drain Drain Curb Cuts, □ Before Storm/ Notification of curb cuts at presettling zones, from the curb cut at the As directed □ Facility is NOT ready for a storm event: moderate to Catch Basins Storm Event first cell after presettling and from the curb cut at the □ Facility is ready for a storm event: minor blockage □ Blockage following heavy blockage from debris, sediment or vegetation, (CB), Trench □ After Storm Event low point or corner from debris, sediment or vegetation, minor ponding weather event damaged structures, and/or visible ponding Drains and Weirs □ After CSO Notification □ Remove blockages from all curb cuts if time allows. □ Remove blockages from weirs and last CB

See Major Corrective Action Long-Term Maintenance Table for Emergency Conditions / Extreme Events

A. Facility Footprint □ Fill in erosion gullies and clean up washouts □ Install temporary erosion control measures until permanent repairs are made March March □ Identify and remedy what is causing erosion and/or □ Moderate erosion, channelization or scouring with □ Heavy erosion, channelization or scouring with □ Erosion and washouts September September washouts less than 40% bare spots greater than 40% bare spots October □ Add cobbles or other erosion protection measure where concentrated water flows □ See Major Corrective Table □ Add mulch when settlement is 2 inches or less - see □ Adjacent to pavement, maintenance holes and at □ Adjacent to pavement, maintenance holes and at E. Mulch. crossings: settlement is 2 inches or less crossings: settlement is 2 inches or greater □ Maintain design width of compacted shoulder (18 March March July □ Settlement inches min.) □ Adjacent to pipe outfalls and overflow structures: □ Adjacent to pipe outfalls and overflow structures: September □ See Major Corrective Maintenance Table when September settlement is 4 inches or less settlement is 4 inches or greater October settlement is reaches unacceptable levels (more than 2 □ Lower slopes and bottom areas: settlement is 6 □ Lower slopes and bottom areas: settlement is 6 inches) inches or less inches or greater March March □ Excessive exposed soils □ Add plants - see D. Vegetation □ Bottom zone plant coverage approximately 70% □ Bottom zone plant coverage less than 70% Perform weeding and routine maintenance work September October A1 Soils when soils are not saturated to prevent compaction □ Attempt to identify clogging issue and remedy source and damage to soil structure of sediment □ Remove sediment in clogged area using a rake or March March vacuum and removing 1 to 3 inches of mulch and July □ Sediment accumulation □ Heavy sediment and water is not draining September replacing with new mulch September □ Moderate sediment and water is draining □ If sediment affects more than a 3-foot by 3-foot area October or is more than 1-inch deep see Major Corrective Maintenance Table □ Observe surface conditions especially downstream from presettling and curb cuts and report non-draining Every visit swales □ Check cleanouts / observation ports for standing □ Soils free draining with no standing water observed □ Water is not draining March □ Soils appear compressed and ponding observed 24 water - see Underdrain System if standing water 24 hours after storm event September hours following rain observed As needed □ If no standing water observed in cleanouts or observation ports use pitchfork or other tined or aerating tool to aerate soil March □ Observe conditions every visit □ Blockage July September □ Pull out rock or boulders to remove surface □ Moderate blockage, trash, debris, sediment and fall □ Heavy trash, debris, sediment and fall leaf litter at A2 Check Dams □ Backed up water September and after 1 inch and greater storms blockages, debris, sediment and fall leaf litter, then leaf litter at check dam check dams □ Undercutting October reinstall January

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 1 of 9 SPU/WTD GSI Program Management SPU #C12-004 ROUTINE MAINTENANCE GUIDANCE FOR MATURE GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW PERFORMANCE STANDARD ADDITIONAL INFO Frequency (Schedule for Full Review 5X GSI Facility Observation Month Unacceptable Comments per year. Jan. March. June. Acceptable Component (Walk facility-look for conditions that Maintenance Activity (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Sept. Nov.; below are may trigger maintenance activity) (Targeted Standard) Required) specialized visits that may be concurrent) A. Facility Footprint Cont.

□ Observe conditions every visit March □ Moderate blockage, trash, debris, sediment and fall □ Heavy blockages, trash, debris, sediment and fall □ Remove surface blockages, debris, sediment and July leaf litter at weirs leaf litter at weirs □ Blockage fall leaf litter □ Backed up water October □ Boulder weirs are intact and relatively level □ Damaged weirs March □ Check and report damaged or unlevel boulder weirs A3 Weirs □ Undercutting January □ Weir plates are attached □ Weir plates are not attached September □ Check that special weir plates are attached □ Damaged weirs □ Dislodged cobbles □ Repair undercuts at sides by replacing soil with clay March dam and installing cobbles □ Minor undercutting, weir base not exposed □ Undercutting exposes base of weir October □ Reset cobbles if they have become dislodged □ Separation from sidewalk or curb □ Displacement of wall at cracks □ Minor cracks in concrete walls edge April □ Observe and report issues every visit □ Separation of joints in segmental walls greater than As directed □ Separation of joints in segmental walls of 1/4 inch 3 □ Leaning August □ Visit after large storms 1/4 inch 2 feet apart feet apart □ Cracked □ See Major Corrective Maintenance Table Vertical Walls: □ Every visit □ Observe and report issues Concrete, □ April before □ Top segmental wall loose A4 □ Rockery loose □ Take corrective action to repair or prevent minor Segmental, April school out □ Rockery unstable or missing rocks □ Segmental wall top uneven/ cap displacement □ Minor weeds in rockery Rockery August □ August □ Rockery imbedded with weeds missing □ Major issues see Major Corrective Maintenance before school □ Weeds coming through segmental joints Table starts □ Heavy accumulation of moss that's moving into □ Accumulation of moss March □ Remove moss/pressure wash March □ Moss is an aesthetic issue, not a performance issue vegetation or onto sidewalk. □ Observe conditions every visit □ Settling, undercutting or blocked March □ Reset cobbles at drain curb cut entries and at base □ Heavy blockage cobbles at drain curb cuts and grates Every visit □ Minor blockage September of weirs and grates □ Settling, undercutting or erosion Boulders, □ Displaced cobbles A5 □ See D. Vegetation for blockage cobbles etc □ Check boulders at pipe outfalls and reset if □ Pipe outfalls without boulder or other type of armour March □ Displaced boulders displaced Every visit □ Pipe outfalls protected protection September □ Receive approval prior to removal of boulders □ Displaced, random boulders

□ Curb side: width of compacted shoulder is 24+/- □ Curb side: width of compacted shoulder is less than Compacted inches 18 inches shoulder at curb □ Shoulder has weed cover of less than 25% □ Vegetation growing in the road shoulder or plants March □ Maintain design width of compacted shoulder by A6 and edge of □ Settlement or insufficient edge As directed □ Vegetation growing in the road shoulder or plants overhanging into the shoulder more than 12 inches September topdressing and recompacting edges sidewalk overhanging into the shoulder less than 12 inches □ Shoulder has weed cover of more than 25% (surfacing varies) □ Sidewalk side: width of compacted shoulder is 8 to12 □ Sidewalk side: width of compacted shoulder is less inches than 8 inches

B. Surface- Inlets/Outlets/Pipes/Grates, Etc.

Weekly: Sept □ Trash, debris, sediment and leaf March □ Remove surface trash debris, sediment and fall leaf thru Mar □ Minor trash, debris and sediment at drain curb cuts □ Moderate trash, debris and sediment at drain curb litter September litter Monthly: Apr because these are the primary points of water entry cuts thru Aug Drain Curb Cuts B1 January (Gutter Line) March March □ Remove blockages July □ Minor blocking at drain curb cuts on planter side of □ Heavy blockage at drain curb cuts causing □ Blockages September □ Remove thick vegetation September curb stormwater to bypass bioretention October November

Trench Drain Grates (including March □ Remove surface trash debris, sediment and fall leaf □ Moderate trash, debris and sediment at trench drain □ Heavy trash, debris and sediment plugging trench B2 □ Debris, sediment and leaf litter Monthly covers at some September litter grates drain grates Drain Curb Cuts)

□ Every visit □ April before April □ Report if exposed opening exceeds 5 inches. See □ Minor damage to wall opening leaves opening less □ Heavy damage to wall opening leaves opening more Planter Wall □ Damage to wall opening school is out August Major Corrective Maintenance Table than 5 inches wide than 5 inches wide B3 Openings (along □ August before Sidewalk) school starts

□ Trash, debris, sediment and leaf See B. Drain Curb Cuts (Gutter Line) litter blockages

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 2 of 9 SPU/WTD GSI Program Management SPU #C12-004 ROUTINE MAINTENANCE GUIDANCE FOR MATURE GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW PERFORMANCE STANDARD ADDITIONAL INFO Frequency (Schedule for Full Review 5X GSI Facility Observation Month Unacceptable Comments per year. Jan. March. June. Acceptable Component (Walk facility-look for conditions that Maintenance Activity (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Sept. Nov.; below are may trigger maintenance activity) (Targeted Standard) Required) specialized visits that may be concurrent) B. Surface- Inlets/Outlets/Pipes/Grates, Etc. (cont.)

January March □ Trash, debris, sediment and leaf March □ Remove surface trash debris, sediment and leaf □ Moderate trash, debris and sediment at entry and □ Heavy trash, debris and sediment at entry points and B4 Presettling September litter September litter pad zone settling or energy pad zones October November □ Remove surface trash debris, sediment and fall leaf Weekly: Sept litter □ Trash, debris, sediment and leaf March thru Mar □ Moderate trash, debris and sediment at grates and □ Heavy trash, debris, and/or sediment at grates and Specialized crew may be required to clean out □ Look into structure for debris especially on beehive litter September Monthly: Apr trash racks trash racks structure grates with open sides. Report if debris at base of thru Aug structure. January Grates and B5 March Trash Racks January □ Heavy blockage of sediment and/or plants blocking □ Blockages □ Remove blockages September □ Moderate blockage at pipe outfalls and CB grates September at trash racks and grates October November March □ Check for and report damage to grates and trash □ Damage As directed □ See Major Corrective Maintenance Table □ See Major Corrective Maintenance Table September racks □ Remove surface trash debris, outfall sediment and □ Heavy debris and sediment in upstream CBs (=/- fall leaf litter March 6inches in sump March □ If sediment in pipe appears to be accumlating to July □ Moderate sediment at CBs and storm drains □ Debris, sediment and leaf litter □ Heavy debris and sediment blocking discharge from September more than 2 inches then jet vacumn or use high September discharging to swales CBs and storm drains discharging to swales-+/- pressure nozzle at upstream end to move sediment to October 2inches in pipes Catch Basins presettling and then remove. (CBs) with pipes January B6 March discharging to March □ Blockages □ Remove blockages September □ Minor blockage at CB grates and pipe outfalls □ Heavy blockage at CB grates and pipe outfalls swales September October November March □ Heavy damage such as cracked structure or March □ Damaged structures □ Check for and report damage July □ Minor damage displaced lid September September □ See Major Corrective Maintenance Table

Surface Clean □ If cover missing immediately cover with temporary □ Cover missing □ Cover present but has some vegetation growing over Outs / □ Cover intact March cover and report. □ Surface cover has become buried under soil B7 As directed □ Clean out port has no accumulated water or Observation □ No water observed September □ Remove clean out cover and do a visibility check for □ Water or debris in clean out. sediment Ports water or debris - see B. Subsurface if water present □ See Major Corrective Maintenance Table

□ Inform crews that geotextile fabric may be present under mulch, rock cobbles or boulders and to reinstall Typically this might be a black or gray woven Geotextile if encountered B8 □ Exposed fabric Yearly As directed □ Minor exposure of fabric (less than 2 inches) □ Fabric pulled out and unsightly material or it might be a manufactured coir blanket Fabrics □ Check for pulled up or unsightly geotextile fabric that material may be under cobbles or boulders etc. Reinstall under boulder or cover with mulch. Trim as applicable.

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 3 of 9 SPU/WTD GSI Program Management SPU #C12-004 ROUTINE MAINTENANCE GUIDANCE FOR MATURE GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW PERFORMANCE STANDARD ADDITIONAL INFO Frequency (Schedule for Full Review 5X GSI Facility Observation Month Unacceptable Comments per year. Jan. March. June. Acceptable Component (Walk facility-look for conditions that Maintenance Activity (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Sept. Nov.; below are may trigger maintenance activity) (Targeted Standard) Required) specialized visits that may be concurrent) C. Subsurface- Inlets/Outlets/Pipes -Etc

Catch Basins March □ Check for and remove blockages and sediment from March □ Moderate blockage at storm drain pipe. Water flow □ Heavy blockage at storm drain pipe. Water does (CB) with Storm □ Pipe blockages September storm drain pipes September has minor restriction through pipe. not flow through pipe. Drains Discharging to □ Remove sediment build-up and/or obstructions from Swales March March □ CB Sediment catch basin sump if more than 6 inches or blocking □ Less than 6 inches of sediment in the CB □ 6 inches or more of sediment in the CB C1 or September September pipes CBs with Pipes Discharges from Cells to March □ CB interior damage September □ Check for and report interior damage to CB □ Minor damage to interior CB □ Heavy damage to interior of CB Downstream September System March March □ Heavy blockage and water is not flowing freely into C2 Flow splitters □ Pipe or weir blockages □ Check for and remove blockages □ Water flow has minor restrictions September September cells March □ Moderate blockage at drain curb cuts, pipe outfalls □ Heavy blockage in trench drain and water does not □ Blockage □ Remove blockages September March and CB grates flow through C3 Trench Drains October September □ Damaged structures □ Check for and report damage to grates or frames As directed □ See Major Corrective Maintenance Table □ See Major Corrective Maintenance Table

□ Check underdrain outlet point for standing water (e.g. MH outlet plugged, UIC MH or drilled drain access structure plugged) causing water to backup into underdrain □ Minor ponding that dissipates within 48 hours - report □ Ponding (i.e. water surface) that lasts more than 72 □ If standing water observed in underdrain outlet point, ponding more than 48 hours hours beyond a storm event □ Water ponding Monthly see maintenance activities for corresponding Monthly Underdrain □ Saturated soil in November, December, January, □ Saturated soil (when non-irrigated) in June, July, downstream infrastructure (e.g. UIC, drilled drain or System February August, September (Maintenance downstream MH) Holes (UMH), □ Check for and report damage to UMH, cleanout or C4 Underdrain underdrain Pipes, □ Video the underdrain if it appears broken/damaged Cleanouts and March □ Remove blockages and sediment from UMHs, March □ Moderate blockage at UMHs, cleanouts and □ Heavy blockage at UMHs, cleanouts and underdrain Observation □ Blockages September cleanouts and underdrain pipes September underdrain pipes pipes Ports) □ Check for and report damage to UMH, cleanout or underdrain March □ Minor damage to interior of UMH, cleanout or □ Heavy damage to interior or UMH, cleanout or □ Damage September □ Remove clean out cover and do a visibility check for September underdrain underdrain debris □ Video the underdrain if it appears broken/damaged □ Crews informed on special New Crews □ Inform new crew members of lined cell locations and □ Crews are informed of lined cell locations and liner □ Crews are not informed of lined cell locations and requirements for digging at liner As directed Yearly special liner requirements requirements the liner requirements locations □ Flag in the field, mark address and location on a plan □ Accidental puncture (not visible) and report if there is the possibility a liner was □ Location of possible accidental puncture/damage to □ Accidental puncture of liner due to activity is □ Observed vehicle wheel track in _ _ Take note of cells locations with liners to prevent accidentally punctured or damaged liner due to activity are reported and flagged unreported cell side or bottom puncturing of liner. Cells may be fully lined or lined □ See Major Corrective Maintenance Table just at the underdrain. Liners may have been Liners (important □ Report if there is no ponding water and no water is installed to go around trees and large shrubs. to refer to project □ Water not ponding and no water in coming through underdrain to UMH during an exteded □ No visible sign of water ponding and water in □ Report of downslope seepage may trigger need to C5 plans for liner March March underdrain during rain event or major rain event underdrain during storm event investigate if related to liner, see Major Corrective type and October October □ Downslope seepage □ Report if there are reports of downslope seepeage □ No reports of downslope seepage Maintenance Table function) □ See Major Corrective Maintenance Table □ What's the liner type? Clay? PVC? etc. □ Inspect exposed liner for damage □ Liner is not exposed and has adequate cover of not □ Where's the tear location - upstream, ○ Liner exposed □ If no damage observed, replenish soil and mulch □ Exposed liner March March less than 18 inches downstream? ○ Visible puncture, tear, cracking or above liner to design depths □ Damage to liner (punctures, tears, or cracking) September September □ Minor damage to liner (punctures, tears, or cracking) □ What's function of liner - keep water out of other degradation of liner □ If damage observed, note location of damage and greater than 1 inch measured in longest direction less than 1 inch measured in longest direction neighboring basements or separate from report biohazardous soils? See Project Plan. □ Observe and Report issues such as adjacent area □ Stormwater function ponding or presence of algae March □ If issues to report see also Major Corrective □ Ponding February □ No issues observed □ Corrective action to repair see Major Corrective September Maintenance Table Soil Cells □ Algae on edges or surface C6 Maintenance Table (Silva Cell ®) □ Observe and Report issues such as pavement March □ If issues to report see also Major Corrective □ Grade breaks or sloughs September cracking in the area or settlement □ No issues observed September Maintenance Table □ See Major Corrective Maintenance Table

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 4 of 9 SPU/WTD GSI Program Management SPU #C12-004 ROUTINE MAINTENANCE GUIDANCE FOR MATURE GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW PERFORMANCE STANDARD ADDITIONAL INFO Frequency (Schedule for Full Review 5X GSI Facility Observation Month Unacceptable Comments per year. Jan. March. June. Acceptable Component (Walk facility-look for conditions that Maintenance Activity (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Sept. Nov.; below are may trigger maintenance activity) (Targeted Standard) Required) specialized visits that may be concurrent) D. Vegetation □ Inform crews that fabric may be present under □Typically this might be a black or gray woven material or Generally filter fabric is used to separate Yearly and as part of crew mulch, rock cobbles or boulders and to reinstall if □ See comments under B. Surface above □ Geotextile fabrics exposed As directed it might be a manufactured coir blanket material. construction materials or to provide some stability instruction encountered. □ Do not use fabric for weed control □ See comments under B. Surface above under cobbles and boulders at installation □ See comments under B. Surface above

March □ Divide perennials, grasses and emergents to replace □ Dead plants or bare areas in facility □ Swale bottom coverage by emergents and vegetation □ Swale bottom coverage by emergents and vegetation Take care to minimize damage while working April dead plants or fill in bare areas - see Perennials and As directed bottom is greater than 70% is less than 70% around perennials, grasses and emergents September Deciduous/Evergreen Grasses and Emergents

March □ Remove trash, debris and pet waste □ Trash, pet waste, heavy leaf litter and/or downed □ Trash debris and pet waste March July □ Minor trash, debris and pet waste. □ Report repeated pet waste branches. □ Contaminants September September □ No contaminants. □ Report contaminants or human waste immediately □ No contaminants. October General: Facility □ One or more plant species is crowding out and □ Maintain 1 foot zone clear of vegetation around all bottom area, harming the vitality of other plants D1 inlets and outlets March slope and top □ Minor blockage from plants at drain curb cuts, weirs, □ Plant growth preventing flow If problem is persistent consider plant species □ Plant blockage March □ Report problem prior to removal or replacement of July vegetation and CB grates. □ Plant growth over curbs or across pavement by 6 +/- replacement in location. Choose from approved GSI □ Aggressive/spreading plants September problem vegetation September □ One plant species is spreading more than other plants inches Plant list. See GSI Design Manual. □ See Major Corrective Maintenance Table for difficult October □ Removal of individual plants solves issue □ Heavy blockage from plants at drain curb cuts, weirs, plants to remove and CB grates □ Prune, trim or thin overhanging plants □ Redefine planting area edges - if trimmers are used □ Plants are growing 6 inches or less over adjacent September is back to school month so clear □ Overhanging evergreen shrubs March March □ Plants are growing more than 6 inches over adjacent keep them 2 feet back from tree trunks paved areas or the adjacent bed or lawn areas sidewalk and sight clearance along roads is and ground covers September September paved or lawn and planting areas maintained by others □ Report prior to removal or replacement of problem maintained by others important vegetation □ Trim or thin overhanging plants □ Redefine planting area edges (keep trimmers 2 feet □ Plants are growing 6 inches or less over adjacent □ Overhanging perennials, deciduous May June □ Plants are growing more than 6 inches over adjacent back from tree trunks) paved areas or the adjacent bed or lawn areas shrubs and grasses September September paved or lawn and planting areas maintained by others □ Report prior to removal or replacement of problem maintained by others vegetation □ Vegetation is over 24 inches at intersection and sight □ Vegetation is slightly over 24 inches at intersections March clearance zones and sight clearance zones and slightly over 30 inches □ Cut back vegetation for sight clearance May □ Vegetation overhangs sidewalk, curbs and/or ramps □ Overgrowth March along swale □ See Major Corrective Maintenance Table for July more than 6 inches Vegetation □ Blocked sight clearance September □ Vegetation overhangs sidewalks, curbs and/or ramps Excessive Vegetation September □ Predominant vegetation along swale is over 36 inches adjacent to areas by less than 6 inches October and visibility is impaired through planter D2 where visibility or □ Visibility is partially impaired through planter □ Perennials and grasses are not trimmed access needs to March be maintained □ Clear vegetation from within 24 inches of fire May □ Fire hydrant is not clearly visible or accessible □ Blocked visibility March hydrants □ Fire hydrant access clearly visible and accessible July □ Maintenance hole access not visible and/or access is □ Blocked access September □ Clear vegetation around maintenance holes for □ Maintenance hole access visible and accessible September blocked access October □ Review water coverage □ Apply compost or arborist wood chip mulch as fertilizer (See E. Mulch) □ Less than 70% of planted vegetation is healthy and March □ Over 70% of planted vegetation is healthy and with a □ Send a sample of soil to soil testing laboratory to with a generally good appearance March July generally good appearance D3 Plant Health □ Unhealthy plants determine what nutrients are deficient □ Plants exhibit signs of significant stress, wilting, September September □ Plants exhibit signs of minor stress, wilting, spotting or □ Report multiple dead or dying plants and coordinate spotting or holes in leaves, broken leaders or branches, October holes in leaves removal and replacement within 30 days leaning trees □ Disinfect gardening tools after pruning diseased plants

□ Prune up limbs for clearance over sidewalk (8 feet) □ Most branches meet clearances over sidewalk (8 feet) and road (14 feet) and road (14 feet) □ Branches do not meet clearance over sidewalk (8 feet) June □ Prune to remove obstructions of street signs, traffic □ Tree has a developed leader or prune to create one and road (14 feet) D4 Trees □ Pruning for clearance and form January Do not prune more than 1/4 of a tree's canopy October signs or street lights □ Trees do no obstruct street signs, traffic signs or street □ Trees obstruct street signs, traffic signs and/or street □ Remove deadwood and crossing branches lights lights □ Remove suckers □ There is little deadwood, crossing branches or suckers

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 5 of 9 SPU/WTD GSI Program Management SPU #C12-004 ROUTINE MAINTENANCE GUIDANCE FOR MATURE GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW PERFORMANCE STANDARD ADDITIONAL INFO Frequency (Schedule for Full Review 5X GSI Facility Observation Month Unacceptable Comments per year. Jan. March. June. Acceptable Component (Walk facility-look for conditions that Maintenance Activity (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Sept. Nov.; below are may trigger maintenance activity) (Targeted Standard) Required) specialized visits that may be concurrent) D. Vegetation (cont.)

□ Small shrubs need minor pruning and pruning is easy □ Prune overhanging vegetation □ Pruning is intense and frequently required - consider and not frequently required June □ Prune/ thin shrubs for visibility and access while February plant species replacement D5 Shrubs □ Pruning □ Larger accent shrubs are pruned up and thinned October maintaining natural shape September □ Shrubs need pruning (windowed) for access and visibility □ Remove deadwood □ Shrubs block access and visibility □ Shrubs are pruned

□ Hand-rake in spring before new growth emerges □ Dead foliage March □ Cut back to 5-8 inches or thin every 2-3 years as March □ Dead foliage is removed in spring □ Dead foliage is not removed Evergreen needed D6 Grasses and Emergents □ Cut back flopping foliage to 24 inches from ground if □ Moderate coverage of adjacent plants and / or □ Heavy coverage of adjacent plants and / or sidewalk □ Flopping foliage June May foliage falls over onto other plants or sidewalk sidewalk by evergreen grass and emergent foliage by evergreen grass and emergent foliage

□ More than 70% of deciduous grasses are healthy □ Less than 70% of deciduous grasses are healthy □ Center dieback □ Divide plants with center dieback May June and with a generally good appearance and no center and with a generally good appearance and no center □ Bare areas □ Divide plants to cover bare areas September dieback dieback □ More than 70% of deciduous grasses are cut back to □ Less than 70% of deciduous grasses are cut back in □ Leave foliage and seedheads however it should be Deciduous 5-8 inches in late winter/early spring before new growth spring before new growth emerges cut back if foliage collapses especially onto other D7 Grasses and □ Flopping foliage May emerges □ Adjacent plants and sidewalk are impacted by grass June plants or sidewalks Emergents □ Dead foliage September □ Plants not crowding out other plants and emergent foliage □ Cut back leaving 5-8 inches in late winter/early □ Moderate coverage of adjacent plants and / or □ Heavy coverage of adjacent plants and / or spring before new growth emerges sidewalk by deciduous grass and emergent foliage sidewalk by deciduous grass and emergent foliage □ Cut off seed heads that extend above 24 inches at March □ Spent seed heads October □ This is an aesthetic issue, not a performance issue □ If visibility/clearance issue locations where sight clearance is critical September

D8 Ferns □ Old foliage February □ Cut back before fronds appear February □ This is an aesthetic issue, not a performance issue. □ If visibility/clearance issue

□ Between 70%-90% of perennials are healthy and with a generally good appearance and no center □ Less than 70% of perennials are healthy and with a □ Divide plants with center dieback □ Center dieback May dieback generally good appearance and no center dieback April □ Divide plants to cover bare areas □ Bare areas September □ Approximately 60% of perennials and deciduous □ Less than 60% of perennials are cut back in spring □ Divide/remove overcrowded plants grasses are cut back in spring before new growth before new growth emerges emerges Perennials and D9 Bulbs □ Leave foliage and seedheads (cut back if foliage □ More than 60% of previous year's perennial foliage May □ 60% of previous year's perennial foliage remains □ Dead foliage April collapses) is not cutback September □ Spring bulb foliage remains if not unsightly □ Cut back in early spring before new growth emerges □ Spring bulb foliage blocks out other plants

□ As time allows remove spent flowers (deadhead) by □ Spent flowers □ This is an aesthetic issue, not a performance issue □ If visibility/clearance issue cutting just above the nearest branch or bud □ Mechanically remove weeds with their roots before they go to seed March □ Apply mulch after first spring and fall weeding (See May □ Less than 20% of the vegetation are weeds March □ Weeds E. Mulch) July □ Difficult weeds to erradicate such as horesetail are □ More than 20% of the vegetation are weeds September □ Routine use of herbicides is prohibited. September controlled so they do not out-compete installed plants D10 Weeds □ For weed infestations see Major Corrective October Maintenance Table □ Weeds in pavement (joints, March □ Mechanically remove weeds by hand or other May □ This is generally an aesthetic issue, not a □ If weed growth causes pavement cracking or cracks) or between pavers September method September performance issue. becomes over 1 inch in height

□ Class A, B & C or non-regulated □ Immediately remove, bag and dispose as garbage noxious weeds all noxious and invasive weeds March □ Greater than 5% noxious weeds present - goal is for □ Invasive weeds of concern such March □ Mechanically remove weeds with their roots before May □ Less than 5% noxious weeds present - goal is for no Noxious and no noxious weeds D11 as bindweed, black locust and June they go to seed July noxious weeds Invasive Weeds □ For weed infestations see Major Corrective September □ Routine use of herbicides is prohibited September buttercup Maintenance Table □ Volunteers such as alder, poplar □ For weed infestations see Major Corrective October and scotch broom Maintenance Table

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 6 of 9 SPU/WTD GSI Program Management SPU #C12-004 ROUTINE MAINTENANCE GUIDANCE FOR MATURE GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW PERFORMANCE STANDARD ADDITIONAL INFO Frequency (Schedule for Full Review 5X GSI Facility Observation Month Unacceptable Comments per year. Jan. March. June. Acceptable Component (Walk facility-look for conditions that Maintenance Activity (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Sept. Nov.; below are may trigger maintenance activity) (Targeted Standard) Required) specialized visits that may be concurrent) E. Mulch

□ Mulch coverage is less than 80% and less than 2 □ Weed prior to applying mulch □ Mulch coverage is at least 80% and is at least 2 inches deep □ Use arborist wood chip much in cell bottom areas inches deep □ Mulch within 8-12 inches of tree trunk flares □ Areas bare of mulch and plants □ Use approved source compost mulch for □ Mulch against shrub stems □ Excessive mulch March February amendment E1 Mulch □ Exposed coir fabric or filter fabric. September □ Remove mulch within 8-12 inches of tree trunk flares See B. Surface October □ Add or remove mulch to maintain depth of 2-4 inches keeping it back from stems of plants □ Minor amount of mulch is blocking the drainage □ Heavy amount of mulch is blocking the drainage □ Remove mulch that is blocking inlets and structures structures and/or curb inlets structures and/or curb inlets

F. Watering

Once a week □ Confirm water source for crews some sites have June, July, irrigation systems and others require source. Special August; more Watering permits may be required if using Fire hydrants as □ Drought June frequently and □ Plants show a few signs of stress, including pests (hand from source. □ Plants are stressed (pests and disease), leaves F1 □ Wilted or stressed plants July longer and disease, or wilting and there are no areas bare of nearby source or □ Water deeply applying approximately 1 inch of water wilting or visible branch die off □ Areas bare of plants August depending on plants due to poor coverage water truck) per week weather and □ Use tree watering bags for replaced or poor type and size of performing trees cell □ Turn on system and check the coverage. Repair □ Irrigation system is working (e.g. there are a few □ System start up May heads and/or add heads as needed for head-to-head June broken parts; coverage is slightly uneven; broken □ Irrigation system is not working. (e.g. coverage is coverage equipment or lines to be capped - hand water until uneven, areas unusually dry or wet; there are areas system is repaired) bare of plants due to coverage; soils washed out) □ Drought □ Activate system earlier or adjust timer schedule if _ See Major Corrective Maintenance Table for June □ Plants show a few signs of stress (including pests □ System needs immediate repair □ Wilted or stressed plants top 1 to 2 inches of soil are dry or if plants are wilted or drought conditions August and disease), wilting, and there are no areas bare of □ Plants are stressed, wilting or dying F2 Irrigation system □ Areas bare of plants stressed. plants due to poor coverage □ System has been winterized prior to freezing □ Winterize system October □ Winterize system October □ System was not winterized prior to freezing weather weather May or June or May □ Conduct test by certified backflow assembly tester □ Backflow assembly annual test if repairs are □ Passed test □ Failed test: make repairs and repeat test until pass and if repairs are made □ Submit report to agency made

Deep Infiltration (over 6 Feet) - this treatment is new and recommendations for routine O&M procedures and corrective actions are under review. Refer to project specifc O&M guidance examples in the Appendix.

□ Download and replace electronic datalogger (if installed) □ 2 feet or more of standing water when no inflow is □ Automated water level □ Create visual record (hydrograph) of water level □ Less than 2 feet of standing water in UIC Well when occurring in MH March UIC Screen Well measurement March fluctuations from datalogger. no inflow is occurring into MH □ Anomalous water level measurements that indicate September & Maintenance □ Maual water level measurement September □ Report datalogger data and perform and report □ No anomalous water level measurements change in conditions (e.g. screen plugging or other Hole (UICMH) downhole video survey if more than 2 feet of standing reduction in well performance) G1 and Underdrain water or anomalous water level measurements Maintenance □ Remove sediment from UMHs & UICMHs with hand Holes (UMH) □ Sediment Accumulation in UICMH March tools or vactor truck March □ Less than one inch of sediment has accumulated in □ More than 1 inch of sediment has accumulated in & UMH September □ Review bioretention facility as possible source of September UMHs & UICMHs UIC screen well MH or underdrain MH heavy sediment □ Damaged monitoring port, well cap March March □ Minor damage is observed to monitoring port, well □ Heavy damage is observed to monitoring port, well □ Report if damage is observed or air vent September September cap or air vent. cap or air vent. □ Check Observation Port/ Standpipe for standing □ Observation Port/ Standpipe has more than 6 water and sediment build-up □ Observation Port/ Standpipe has less than 6 inches inches of standing water within 72 hours following March □ Report standing water for follow up visit March of standing water within 48 hours following storm event □ Standing water storm event September □ Check for sediment build-up on surface of cell with September □ No standing water within 24 hours following storm □ Standing water observed in cell with pit drain more pit drain event than 48 hours after storm even Pit Drains & □ Remove sediment - see A. Facility Footprint G2 Observation Port March March □ Moderate blockage at UMHs, cleanouts and □ Heavy blockage at UMHs, cleanouts and underdrain □ Blockages □ Clear blockages September September underdrain pipes pipes □ Check for and report damage to UMH, cleanout or March □ Minor damage to interior of UMH, cleanout or □ Heavy damage to interior or UMH, cleanout or □ Damage September underdrain September underdrain pipes underdrain □ Video the underdrain if it appears broken/damaged

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 7 of 9 SPU/WTD GSI Program Management SPU #C12-004 ROUTINE MAINTENANCE GUIDANCE FOR MATURE GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW PERFORMANCE STANDARD ADDITIONAL INFO Frequency (Schedule for Full Review 5X GSI Facility Observation Month Unacceptable Comments per year. Jan. March. June. Acceptable Component (Walk facility-look for conditions that Maintenance Activity (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Sept. Nov.; below are may trigger maintenance activity) (Targeted Standard) Required) specialized visits that may be concurrent) Deep Infiltration (over 6 Feet) - this treatment is new and recommendations for routine O&M procedures and corrective actions are under review. Refer to project specifc O&M guidance examples in the Appendix. (cont.)

□ Less than 2 feet of standing water 24 hours after □ More than 2 feet of standing water 24 hours after storm event storm event ○ Standing water in drilled drain - □ Remove sediment from drilled drain conveyance □ Less than 6 inches of sediment accumulation in □ More than 6 inches of sediment accumulation in This is a placeholder. UIC screen well maintenance is manual water level measurement March pipe March bottom of conveyance pipe. Depth of sediment bottom of conveyance pipe. Depth of sediment based on WTD's Barton O&M manual issued in 2014. ○ Sediment acculumation in September □ Report if standing water observed. September estimated based on depth of conveyance pipe during estimated based on depth of conveyance pipe during See appendix for examples. conveyance pipe See Major Corrective Maintenance Table inspection compared to depth of conveyance pipe post- inspection compared to depth of conveyance pipe post- construction (as measured from rim of structure). construction (as measured from rim of structure).

□ Remove sediment and fouled sand layer(s) from This is a placeholder. UIC screen well maintenance is drilled drain with hand tools or vactor equipment based on WTD's Barton O&M manual issued in 2014, □ Replace sand layer(s) minimum xx (Refer to project See Appendix for examples. FOR ACCEPTABLE □ Less than 1/8 inch of sediment has accumulated in G3 design documents) □ More than 1/8 inch of sediment has accumulated in COLUMN: Per conversation with AESI - very minor Drilled Drains □ Sediment accumulation in access drilled drain March □ Review bioretention facility components as possible March drilled drain sedimentation will decrease the sand infiltration rate, structure (Reinforced Concrete Pipe) □ No standing water in drilled drain structure (above September source of sediment loading (e.g., cracked cleanout or September □ Standing water in drilled drain structure (above sand and thus drilled drain performance (increasing risk of □ Standing water in access structure sand layers) when no inflow from underdrain is underdrain pipe) layers) when no inflow from underdrain is occurring drain failure). Sedimentation should also be a flag occurring □ If standing water observed, ensure sand that there is an issue upstream in the treatment train replacement alleviates issue. If not, report. See Major (design anticipates very little sediment accumulation Corrective Maintenance Table within drain)

○ Damaged access structure ○ Damaged or missing frame or □ Minor damage not impacting drilled drain □ Heavy damage potentially impacting drilled drain cover March □ Report damage or missing components March This is a placeholder. UIC screen well maintenance is performance performance ○ Damaged or missing vertical September □ Repair and replace as necessary September based on WTD's Barton O&M manual issued in 2014. □ No missing components □ Missing components conveyance pipe top section, cap, screen, or hose clamps. H. Permeable Pavement This section is a placeholder - further discussion on GSI facility applications for permeable pavements Pervious March □ Heavy amount of debris on permeable pavement Concrete (Full March □ Vacuum Sweep both curb lines of entire street and □ Moderate debris on pavement but not affecting H1 □ Sediment/ leaf debris/ moss October and during rain events water ponds or runs off Street Length & October (after leaf drop) through each intersection drainage function during rain event (after leaf drop) permeable pavement Width) Previous March □ Heavy amount of debris on permeable pavement Concrete in March □ Vacuum Sweep both curb lines of entire street and □ Moderate debris on pavement but not affecting H2 □ Sediment/ leaf debris/moss October and during rain events water ponds or runs off partial width or October (after leaf drop) through each intersection drainage function during rain event (after leaf drop) permeable pavement length of street Pervious March □ Heavy amount of debris on permeable pavement March □ Vacuum Sweep alley (edge to edge) of entire alley □ Moderate debris on pavement but not affecting H3 Concrete Alley □ Sediment/ leaf debris/moss October and during rain events water ponds or runs off October (after leaf drop) through each intersection drainage function during rain event (Full or Partial) (after leaf drop) permeable pavement Pervious □ Heavy amount of debris on permeable pavement Fall □ Moderate debris on pavement but not affecting H4 Concrete □ Sediment/ leaf debris/moss 1x/year □ Vacuum Sweep/Pressure Wash and during rain events water ponds or runs off Spring drainage function during rain event Sidewalk permeable pavement □ Remove debris, soil that has deposited onto the Areas Adjacent to □ Soils are eroding and heavy amount of debris has pavement □ Minor amount of soil erosion and moderate debris Porous □ Check if adjacent areas are Fall been deposited onto permeable pavement and during H5 1x year □ Vacumn area of impacted permeable pavement on pavement but not affecting drainage function during Pavement that stabilized. No exposed soil. Spring rain events water ponds or runs off permeable □ Mulch and/or plant exposed soils that may erode to rain event drain onto porous pavement pavement surface Maintenance and Repairs Adjacent □ Repairs adjacent to porous □ Cover porous pavement when working on adjacent □ Porous pavement is completely covered and □ Porous pavement is not completely covered and H6 _ _ to Permeable pavement landscape areas to prevent debris accumulation protected during repairs protected during repairs Pavements

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 8 of 9 SPU/WTD GSI Program Management SPU #C12-004 ROUTINE MAINTENANCE GUIDANCE FOR MATURE GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW PERFORMANCE STANDARD ADDITIONAL INFO Frequency (Schedule for Full Review 5X GSI Facility Observation Month Unacceptable Comments per year. Jan. March. June. Acceptable Component (Walk facility-look for conditions that Maintenance Activity (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Sept. Nov.; below are may trigger maintenance activity) (Targeted Standard) Required) specialized visits that may be concurrent) I. Hardscape/Specialty Elements

□ Sweep both curb lines of entire street March □ Moderate road gutter debris on blocks with □ Heavy road gutter debris on blocks with bioretention I1 Street Surface □ Road gutter debris □ Sweep both curb lines for 1 block of intersecting Per COS September bioretention facilities facilities streets upstream of the bioretention facilities

Sidewalks March March □ Less than 40% of pavement is covered with light □ More than 40% of pavement is covered with moss □ Moss □ Clean pavement (see also H. September September moss □ Thick moss is more than 20% I2 Permeable March March □ Less than 20% of pavement is covered with debris, □ More than 20% of pavement is covered with debris, Pavement) □ Debris, leaves and sediment □ Clean pavement 4 foot continuous clearance required September September leaves and sediment leaves and sediment □ Rake or add mulch to level it out - see E. Mulch □ Remove weeds - see D. Vegetation March □ Weeds in mulch March □ Less than 20% of mulch is uneven or weedy □ More than 20% of mulch is uneven or weedy □ See A. Facility Footprint and E. Mulch for settlement. October □ Mulch settlement September □ See A. Facility Footprint for compacted shoulder at (after leaf drop) curb and edge of sidewalk March □ Rake or add gravel to level it out. March July □ Remove weeds. See D. Vegetation. □ Less than 20% of gravel is uneven or weedy □ More than 20% of gravel is uneven or weedy September September Paved Paths, □ See A. Facility Footprint for settlement. □ Weeds in gravel October Step Out Zones, I3 □ Gravel settlement □ Add gravel when settlement is 2 inches or less to Curb Edges, March level with adjacent surface March □ Settlement is 2 inches or greater - see Major Access □ Settlement is less than 2 inches September □ See A. Facility Footprint for compacted shoulder at October Corrective and Long-Term Maintenance Table curb and edge of sidewalk March March □ Less than 25% of pavement is covered with moss, □ More than 25% of pavement is covered with moss, □ Moss, debris, leaves and sediment □ Clean pavement October September debris, leaves and sediment debris, leaves and sediment □ Random pavers placed by others □ Report random pavers placed by others □ Uneven pavers March March □ More than 80% pavers are even □ Less than 80% pavers are even □ Reset uneven pavers □ Spaced Pavers with extensive October September □ Less than 20% of paver joints contain weeds □ More than 20% of paver joints contain weeds □ Weed between pavers - see D. Vegetation weeds

□ Review signs are visible and □ Signs are knocked over □ Report knocked over signs upright March March □ Signs are visible and upright □ Interperative signs are inapplicable □ Report inapplicable interperative signs □ Review interpretive signs if October September □ Interpretive signs if applicable □ Trees and shrubs are not pruned for clearance / Signage and □ Prune trees and shrubs for clearance/ visibility I4 applicable visibility Traffic Markers □ Review placement of vertical or on March □ Check and report displaced vertical or on edge March □ Vertical or on edge traffic markers are in place □ Vertical or on edge traffic markers are displaced edge traffic markers at curb bulbs October traffic markers September □ Damage Street □ Vandalism March □ Report damage or vandalism March □ Furnishings and art are visible, unvandalized or □ Furnishings and art are blocked, vandalized or I5 Furnishings / □ Cleanliness October □ Prune trees and shrubs for clearance / visibility September undamaged damaged Public Art □ Visibility

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GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix B: Establishment Period Maintenance Guidance for GSI in the Right-of-Way

GSI Manual, Volume V – Operations & Maintenance Appendix

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SPU/WTD GSI Program Management SPU #C12-004 Date: July 2015 SvR #12034

ESTABLISHMENT PERIOD MAINTENANCE GUIDANCE FOR GSI IN THE RIGHT-OF-WAY Notes: 1. The following table is based on the "Guidance Document: Western Washington Low Impact Development (LID) Operation and Maintenance (O&M)" prepared for Ecology Water Quality Program - July 8, 2013 and the 2014 update to City of Seattle's Stormwater Manual. 2. This table is guidance for the first 3+/- years after installation. Timing is guidance and may be adjusted to site specific conditions. 3. See Examples: Acceptable / Unacceptable Guidance in the appendix of GSI Manual, Volume V. 4. See separate tables for specific guidance for routine and major corrective action / long-term maintenance. 5. Bold Text = High priority for function or safety 6 Orange indicates topic areas that are under development, the guidance included is a placeholder. Refer to project specific O&M guidance in the interim.

OPERATIONS-SUPERVISOR MAINTENANCE-CREW Frequency GSI Facility Observation (Schedule for monthy review; below Component (walk facility-look at conditions that may Maintenance Activity Frequency (Typical) Acceptable are specialized visits that may be trigger maintenance activity) (Targeted Standard) concurrent) Emergency Conditions / Extreme Events □ Before Storm/ Notification of Storm □ Remove at a minimum blockages/leaves from drain curb cuts at presettling zones, from the Drain Curb Cuts, Catch Event curb cut at the first cell after presettling and from the curb cut at the low point or corner As directed following □ Facility is ready for a storm event: minor blockage from debris, sediment or vegetation, minor Basins (CB), Trench Drains □ Blockage □ After Storm Event □ Remove blockages from all curb cuts if time allows weather event ponding and Weirs □ After CSO Notification □ Remove blockages from weirs and last CB

See Major Corrective Maintenance Table for Emergency Conditions / Extreme Events A. Facility Footprint □ Perform maintenance work when soils are not saturated to prevent compaction and damage □ Soil protection during maintenance to soil structure Every visit □ For extensive maintenance place boards to step on to avoid foot compaction □ Fill in erosion gullies and clean up washouts □ Install temporary erosion control measures until permanent repairs are made □ Erosion and washouts Monthly As needed □ Some erosion, channelization or scouring with less than 20% bare spots □ Identify and remedy what is causing erosion and/or washouts □ Add cobbles or other erosion protection measure where concentrated water flows □ Add mulch when settlement is 2 inches or less - see E. Mulch March □ Adjacent to pavement, maintenance holes and at crossings: settlement is 1 inch or less March □ Maintain design width of compacted shoulder (18 inches min.) July □ Settlement September □ See Major Corrective Maintenance Table when settlement reaches unacceptable levels (more September □ Adjacent to pipe outfalls and overflow structures: settlement is 4 inches or less than 2") October □ Lower slopes and bottom areas: settlement is 6 inches or less March □ Excessive exposed soils □ Add plants - see D. Vegetation As directed □ Bottom zone plant and mulch coverage approximately 90% September A1 Soils □ Perform weeding and routine maintenance work when soils are not saturated to prevent compaction and damage to soil structure March □ Attempt to identify clogging issue and remedy source of sediment July □ Sediment accumulation Monthly □ Remove sediment in clogged area using a rake or vacuum and removing 1 to 3 inches of September □ Minor sediment and water is draining mulch and replacing with new mulch October □ If sediment affects more than a 3-foot by 3-foot area or is more than 1-inch deep see Major Corrective Maintenance Table □ Observe surface conditions especially downstream from presettling and curb cuts and report Every visit non-draining swales □ Water is not draining □ Soils free draining with no standing water observed 24 hours after storm event Monthly □ Check cleanouts / observation ports for standing water. See Underdrain System if standing water observed. As needed □ If no standing water observed in cleanouts or observation ports use pitchfork or other tined or aerating tool to aerate soil. March □ Blockage □ Observe conditions every visit July Monthly A2 Check Dams □ Backed up water □ Pull out rock or boulders to remove surface blockages, debris, sediment and fall leaf litter, September □ Minor blockage, trash, debris, sediment and fall leaf litter at check dam and after 1 inch and greater storms □ Undercutting then reinstall October January □ Observe conditions every visit March □ Blockage □ Remove surface blockages, debris, sediment and fall leaf litter July □ Minor blockage, trash, debris, sediment and fall leaf litter at weirs □ Backed up water March □ Check that boulder weirs are intact and relatively level October A3 Weirs □ Undercutting September □ Check that special weir plates are attached January □ Damaged weirs □ Repair undercuts at sides by replacing soil with clay dam and installing cobbles March □ Dislodged cobbles □ No undercutting, weir base not exposed □ Reset cobbles if they have become dislodged October □ Separation from sidewalk or curb edge April □ Observe and report issues every visit □ Minor cracks in concrete walls As directed □ Leaning / Cracked August □ Visit after large storms □ Separation of joints in segmental walls of 1/4 inch 3 feet apart □ Every visit Vertical Walls, concrete, □ Rockery loose □ Observe and report issues □ April before school A4 April □ Segmental wall top uneven/ cap □ Take corrective action to repair or prevent minor displacement out □ Minor weeds in rockery Segmental, Rockery August missing □ See Major Corrective Maintenance Table □ August before school starts

□ Accumulation of moss March □ Remove moss/pressure wash March □ Moss is an aesthetic issue, not a performance issue

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 1 of 7 SPU/WTD GSI Program Management SPU #C12-004 ESTABLISHMENT PERIOD MAINTENANCE GUIDANCE FOR GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW Frequency GSI Facility Observation (Schedule for monthy review; below Component (walk facility-look at conditions that may Maintenance Activity Frequency (Typical) Acceptable are specialized visits that may be trigger maintenance activity) (Targeted Standard) concurrent) A. Facility Footprint (cont.) □ Settling, undercutting or blocked cobbles □ Observe conditions every visit March at drain curb cuts and grates □ Reset cobbles at drain curb cut entries and at base of weirs and grates Every visit □ Minor blockage September A5 Boulders, cobbles etc □ Displaced cobbles □ See D. Vegetation for blockage March □ Check boulders at pipe outfalls and reset if displaced □ Displaced boulders Every visit □ Pipe outfalls protected September □ Receive approval prior to removal of boulders □ Curb side: width of compacted shoulder is 24+/- inches. Compacted shoulder at curb □ Shoulder has weed cover of less than 10% March A6 and edge of sidewalk □ Settlement or insufficient edge □ Maintain design width of compacted shoulder by topdressing and recompacting edges As directed □ Vegetation growing in the road shoulder or plants overhanging into the shoulder less than 6 September (surfacing varies) inches □ Sidewalk side: width of compacted shoulder is 8 to12 inches B. Inlets/Outlets/Pipe/Grates - Surface

March Weekly: Sept thru Mar □ Trash, debris, sediment and leaf litter □ Remove surface trash debris, sediment and fall leaf litter □ Minor trash, debris and sediment at drain curb cuts September Monthly: Apr thru Aug

January March Drain Curb Cuts (Gutter B1 March □ Remove blockages July Line) □ Blockages □ Minor blocking at drain curb cuts on planter side of curb September □ Remove thick vegetation September October November March □ Damage □ Check for and report damage to grates and trash racks As directed □ See Major Corrective Maintenance Table September Trench Drain Grates March B2 (including covers at some □ Debris, sediment and leaf litter □ Remove surface trash debris, sediment and fall leaf litter Monthly □ Minor trash, debris and sediment at trench drain grates September Drain Curb Cuts) □ Every visit □ April before school April □ Report if exposed opening exceeds 5 inches □ Damage to wall opening out □ No damage to wall opening leaves opening less than 5 inches wide Planter Wall Openings (along August □ See Major Corrective Maintenance Table B3 □ August before Sidewalk) school starts □ Trash, debris, sediment and leaf litter See B. Drain Curb Cuts (Gutter Line) □ Blockages January March B3 Presettling □ Trash, debris, sediment and leaf litter Monthly □ Remove surface, trash debris, sediment and leaf litter September □ Minor trash, debris and sediment at entry and pad zone October November □ Remove surface trash debris, sediment and fall leaf litter Weekly: Sept thru Mar □ Trash, debris, sediment and leaf litter Monthly □ Look into structure for debris especially on beehive grates with open sides. Report if debris at □ Minor trash, debris and sediment at grates and trash racks Monthly: Apr thru Aug base of structure. B4 Grates and Trash Racks January March □ Blockages Monthly □ Remove blockages September □ Minorl blockage at pipe outfalls and CB grates October November □ Debris, sediment and leaf litter Monthly □ Remove surface trash debris, sediment and fall leaf litter Monthly □ Minor trash, debris and sediment at CBs and storm drains discharging to swales Catch Basins (CBs) with B5 Monthly □ Remove blockages Monthly □ Minor blockage at CB grates and pipe outfalls Pipes Discharging to Swales □ Blockages □ Check for and report damage □ Damaged structures Monthly Monthly □ No damage to grates, trash racks and structures □ See Major Corrective Maintenance Table

□ If cover missing immediately cover with temporary cover and report. □ Cover intact March □ Cover present but has some vegetation growing over B6 Surface Clean Outs □ Remove clean out cover and do a visibility check for water or debris As directed □ No water observed September □ Clean out port has no accumulated water or sediment □ See B. Subsurface if water presen

□ Inform crews that geotextile fabric may be present under mulch, rock cobbles or boulders and to reinstall if encountered B7 Geotextile Fabrics □ Exposed fabric Monthly As directed □ Minor exposure of fabric (less than 2 inches) □ Check for pulled up or unsightly geotextile fabric that may be under cobbles or boulders etc. Reinstall under boulder or cover with mulch. Trim as applicable.

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 2 of 7 SPU/WTD GSI Program Management SPU #C12-004 ESTABLISHMENT PERIOD MAINTENANCE GUIDANCE FOR GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW Frequency GSI Facility Observation (Schedule for monthy review; below Component (walk facility-look at conditions that may Maintenance Activity Frequency (Typical) Acceptable are specialized visits that may be trigger maintenance activity) (Targeted Standard) concurrent) C. Inlets/Outlets/Pipes - Subsurface March March □ Pipe blockages □ Check for and remove blockages and sediment from storm drain pipes □ Minor blockage at storm drain pipe. Water flow is not restricted through pipe. September September Catch Basins (CB) and March □ Remove sediment build-up and/or obstructions from catch basin sump if more than 6 inches March C1 Storm Drains Discharging □ CB Sediment □ Less than 6 inches of sediment in the CB September or blocking pipes September to Swales March □ CB interior damage September □ Check for and report interior damage to CB □ Minor damage to interior CB September March March C2 Flow splitters □ Pipe or weir blockages □ Check for and remove blockages □ Water flow has minor restrictions September September March □ Blockage □ Remove blockages September □ Minor blockage at drain curb cuts, pipe outfalls and CB grates March C3 Trench Drains October September □ Damaged structures □ Check for and report damage to grates or frames As directed □ See Major Corrective Maintenance Table □ Check underdrain outlet point for standing water (e.g., MH outlet plugged, UIC MH or drilled drain access structure plugged) causing water to backup into underdrain □ If standing water observed in underdrain outlet point, see maintenance activities for □ Minor ponding that dissipates within 48 hours, report ponding more than 48 hours □ Water ponding Monthly Monthly corresponding downstream infrastructure (e.g., UIC, drilled drain or downstream MH) □ Saturated soil in November, December, January, February Underdrain System □ Check for and report damage to UMH, cleanout or underdrain (Maintenance Holes C4 □ Video the underdrain if it appears broken/damaged (UMH), Underdrain Pipes March March and Cleanouts) □ Blockages □ Remove blockages and sediment from UMHs, cleanouts and underdrain pipes □ Minor blockage at UMHs, cleanouts and underdrain pipes September September □ Check for and report damage to UMH, cleanout or underdrain March □ Damage September □ Remove clean out cover and do a visibility check for water or debris □ Minor damage to interior of UMH, cleanout or underdrain September □ Video the underdrain if it appears broken/damaged □ Crews informed on special requirements New Crews □ Inform new crew members of lined cell locations and special liner requirements As directed □ Crews are informed of lined cell locations and liner requirements for digging at liner locations Yearly □ Accidental puncture (not visible) □ Flag in the field, mark address and location on a plan and report if there is the possibility a □ Location of possible accidental puncture/damage to liner due to activity are reported and □ Observed vehicle wheel track in cell side _ liner was accidentally punctured or damaged _ flagged or bottom □ See Major Corrective Maintenance Table. C5 Liners □ Report if there is no ponding water and no water is coming through underdrain to UMH during □ Water not ponding and no water in March an exteded or major rain event March □ No visible sign of water ponding and water in underdrain during storm event underdrain during rain event October □ Report if there are reports of downslope seepeage October □ No reports of downslope seepage □ Downslope seepage □ See Major Corrective Maintenance Table ○ Liner exposed □ Inspect exposed liner for damage. If no damage observed, replenish soil and mulch above □ Liner is not exposed and has adequate cover of not less than 18 inches March March ○ Visible puncture, tear, cracking or other liner to design depths ○ Minor damage to liner. Punctures, tears, or cracking less than 1 inch (measured in longest September September degradation of liner □ If damage observed, note location of damage and notify Project Representative direction). □ Stormwater function □ Observe and Report issues such as adjacent area ponding or presence of algae March □ Ponding February □ No issues observed Soil Cells □ Corrective action to repair seeMajor Corrective Maintenance Table September C6 □ Algae on edges or surface (Silva Cell ®) □ Grade breaks or sloughs □ Observe and Report issues such as pavement cracking in the area or settlement March September □ No issues observed □ Corrective action to repair seeMajor Corrective Maintenance Table September D. Vegetation □ Inform crews that fabric may be present under mulch, rock cobbles or boulders and to reinstall if encountered □ Minor exposure of fabric (<2 inches) □ Geotextile fabrics exposed Monthly □Typically this might be a black or gray woven material or it might be a manufactured coir As directed □ See B. Surface blanket material □ Do not use fabric for weed control □ Dead plants or bare areas in facility □ Divide perennials, grasses and emergents to replace dead plants or fill in bare areas March Monthly □ Swale bottom coverage by emergents, vegetation and mulch is 100%. bottom □ See Perennials, Evergreen and Deciduous Grasses and Emergents September March □ Remove trash, debris and pet waste □ Trash and pet waste July □ Minor trash and pet waste Monthly □ Report repeated pet waste □ Contaminants September □ No contaminants General: facility bottom area, □ Report contaminants or human waste immediately D1 October slope and top vegetation March □ Plants species are growing well together □ Maintain 1 foot zone clear of vegetation around all inlets and outlets □ Plant blockage July □ One plant species is spreading more than other plants Monthly □ Report prior to removal or replacement of problem vegetation □ Aggressive / spreading plants September □ Removal of individual plants solves issue □ See Major Corrective Maintenance Table for difficult plants to remove October □ Minor blockage from plants at drain curb cuts, weirs, and CB grates □ Prune, trim or thin overhanging plants □ Overhanging evergreen shrubs and March March □ Plants are growing 6 inches or less over adjacent paved areas or the adjacent bed or lawn areas □ Redefine planting area edges - if trimmers are used keep them 2 feet back from tree trunks ground covers September September maintained by others □ Report prior to removal or replacement of problem vegetation. □ Trim or thin overhanging plants. □ Overhanging perennials, deciduous May June □ Plants are growing 6 inches or less over adjacent paved areas or the adjacent bed or lawn areas □ Redefine planting area edges - keep trimmers 2 feet back from tree trunks shrubs and grasses September September maintained by others □ Report prior to removal or replacement of problem vegetation

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 3 of 7 SPU/WTD GSI Program Management SPU #C12-004 ESTABLISHMENT PERIOD MAINTENANCE GUIDANCE FOR GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW Frequency GSI Facility Observation (Schedule for monthy review; below Component (walk facility-look at conditions that may Maintenance Activity Frequency (Typical) Acceptable are specialized visits that may be trigger maintenance activity) (Targeted Standard) concurrent) D. Vegetation (cont.) March □ Vegetation is under 24 inches at intersections and sight clearance zones. □ Overgrowth □ Cut back vegetation for sight clearance July □ Vegetation is clear from sidewalk, curbs and ramps. Monthly □ Blocked sight clearance □ See Major Corrective Maintenance Table for Excessive Vegetation September □ Visibility through planter is good. Vegetation adjacent to areas October □ Perennials and grasses are trimmed. D2 where visibility or access March needs to be maintained □ Blocked visibility □ Clear vegetation from within 24 inches of fire hydrants July □ Fire hydrant access clearly visible and accessible Monthly □ Blocked access □ Clear vegetation around maintenance holes for access September □ Maintenance hole access visible and accessible October

□ Review water coverage March □ Apply compost or arborist wood chip mulch as fertilizer - see E. Mulch □ At least 90% of planted vegetation is healthy and with a good appearance. July D3 Plant Health □ Unhealthy plants Monthly □ Send a sample of soil to soil testing laboratory to determine what nutrients are deficient □ Plants are healthy and growing, no wilting, no spotting or holes in leaves, no broken leaders or September □ Report multiple dead or dying plants and coordinate removal and replacement within 30 days branches, trees are plumb. October □ Disinfect gardening tools after pruning diseased plants

□ Prune up limbs for clearance over sidewalk (8 feet) and road (14 feet) □ Tree root flares are exposed and roughly 1 to 2 inches above adjacent curb or sidewalk □ Prune to remove obstructions of street signs, traffic signs or street lights. June □ Branches meet clearance over sidewalk (8 feet) over road (14 feet). D4 Trees □ Pruning □ Remove deadwood and crossing branches January October □ Trees do no obstruct street signs, traffic signs or street lights. □ Remove suckers □ There is little deadwood, crossing branches or suckers. □ Do not prune more than 1/4 of a tree's canopy.

□ Prune overhanging vegetation □ Small shrubs need minor pruning and pruning is easy and not frequently required. June February D5 Shrubs □ Pruning □ Prune/ thin shrubs for visibility and access while maintaining natural shape. □ Larger accent shrubs are pruned up and thinned (windowed) for access and visibility. October September □ Remove deadwood □ Shrubs are pruned.

□ Hand-rake in spring before new growth emerges. □ Dead foliage March March □ Dead foliage is removed in spring. □ Cut back to 5-8 inches or thin every 2-3 years as needed. Evergreen Grasses and D6 □ Cut back flopping foliage to 24 inches from ground if foliage falls over onto other plants or Emergents □ Flopping foliage May sidewalk (due to excessive growth from compost in bioretention soil mix and extra watering for May □ Minor coverage of adjacent plants and / or sidewalk by evergreen grass and emergent foliage. establishment) □ At least 90% of deciduous grasses are healthy and with a generally good appearance and no □ Center dieback □ Divide plants with center dieback March center dieback May □ Bare areas □ Divide plants to cover bare areas September □ At least 80% of deciduous grasses are cut back to 8-10 inches in late winter/early spring before new growth emerges □ Leave foliage and seedheads however it should be cut back if foliage collapses especially Deciduous Grasses and □ More than 90% of deciduous grasses are cutback to 5-8 inches in late winter/early spring D7 □ Dead foliage May onto other plants or sidewalks March Emergents before new growth emerges □ Cut back leaving 5-8 inches in late winter/early spring before new growth emerges March □ This is an aesthetic issue, not a performance issue □ Spent seed heads October □ Cut off seed heads that extend above 24 inches at locations where sight clearance is critical. September □ Visibility / clearance are not blocked □ Cut back foliage to 24 inches from ground if foliage falls over (due to excessive growth from □ Flopping foliage May May □ Minor coverage of adjacent plants and / or sidewalk by deciduous grass and emergent foliage compost in bioretention soil mix and extra watering for establishment) □ This is an aesthetic issue, not a performance issue D8 Ferns □ Old foliage February □ Cut back before fronds appear February □ Visibility / clearance is not an issue

□ Divide plants with center dieback □ At least 90% of perennials and bulbs are healthy with a generally good appearance and no center □ Center dieback April April □ Divide plants to cover bare areas dieback □ Bare areas September September □ Divide/remove overcrowded plants □ At least 60% of perennials perennials and bulbs are cut back in spring before new growth emerges

D9 Perennials and Bulbs □ Leave foliage and seedheads (cut back if foliage collapses) □ 60% of previous year's perennial foliage remains □ Dead foliage March March □ Cut back in early spring before new growth emerges □ Spring bulb foliage remains if not unsightly

□ As time allows remove spent flowers (deadhead) by cutting just above the nearest branch or □ This is an aesthetic issue, not a performance issue □ Spent flowers bud □ Visibility / clearance is not an issue □ Mechanically remove weeds with their roots before they go to seed Once a month: □ Apply mulch after weeding - see E. Mulch February to April □ Weeds Monthly □ Less than 15% of the vegetation are weeds □ Routine use of herbicides is prohibited. Twice a month: May to D10 Weeds □ For weed infestations see Major Corrective Maintenance Table. September □ Weeds in pavement (joints, cracks) or March May □ Mechanically remove weeds by hand or other method □ This is generally an aesthetic issue, not a performance issue between pavers September September □ Class A, B & C or non-regulated noxious weeds □ Immediately remove, bag and dispose as garbage all noxious and invasive weeds. Once a month: March Noxious and Invasive □ Invasive weeds of concern such as □ Mechanically remove weeds with their roots before they go to seed February to April D11 June □ Little or no class A, B, C or non-regulated noxious or invasive weeds present Weeds bindweed, horsetail and buttercup □ Routine use of herbicides is prohibited. Twice a month: May to September □ Volunteers such as alder, poplar and □ For weed infestations see Major Corrective Maintenance Table September scotch broom

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 4 of 7 SPU/WTD GSI Program Management SPU #C12-004 ESTABLISHMENT PERIOD MAINTENANCE GUIDANCE FOR GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW Frequency GSI Facility Observation (Schedule for monthy review; below Component (walk facility-look at conditions that may Maintenance Activity Frequency (Typical) Acceptable are specialized visits that may be trigger maintenance activity) (Targeted Standard) concurrent) E. Mulch

□ Weed prior to applying mulch □ Mulch coverage is at least 90% □ Areas bare of mulch and plants □ Use arborist wood chip much in cell bottom areas □ Mulch is approximately 2-3 inches deep □ Excessive mulch March □ Use approved source compost mulch for amendment March E1 Mulch □ Exposed coir fabric or filter fabric. See B. September □ Remove mulch within 8-12 inches of tree trunk flares September Surface □ Add or remove mulch to maintain depth of 2-3 inches keeping it back from stems of plants □ Minor mulch is blocking the drainage structures and/or curb inlets □ Remove mulch that is blocking inlets and structures

F. Watering 3 times a week May May □ Confirm water source for crews some sites have irrigation systems and others require source. through September; Watering □ Drought June Special permits may be required if using Fire hydrants as source more frequently and □ Plants are healthy and thriving and show no signs of stress, including pests and disease, or wilting F1 (hand from nearby source or □ Wilted or stressed plants July □ Water deeply applying approximately 1-inch of water per week longer depending on and there are no areas bare of plants due to poor coverage water truck) □ Areas bare of plants August □ Use tree watering bags for newly planted trees weather and type September and size of cell. □ Turn on system and check the coverage. Repair heads and/or add heads as needed for head- □ Head to head coverage □ System start up May or June to-head coverage May or June □ Reduce water rate annually □ Adjust watering rates down annually to acclimate plants for routine watering □ Drought □ Water deeply applying approximately 1 inch of water per week 2 to 3 times a week July □ Plants are healthy and thriving and show no signs of stress, including pests and disease, or wilting □ Wilted or stressed plants □ Activate system earlier or adjust timer schedule if top 1 to 2 inches of soil are dry or if plants June through F2 August and there are no areas bare of plants due to poor coverage Irrigation system □ Areas bare of plants are wilted or stressed September □ Winterize system October □ Winterize system October □ System has been winterized prior to freezing weather

□ Conduct test by certified backflow assembly tester May or June or if □ Backflow assembly annual test May and if repairs are made □ Passed test □ Submit report to agency repairs are made F3 Drought See Major Corrective Maintenance Table

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Deep Infiltration (over 6 Feet) - this treatment is new and recommendations for routine O&M procedures and corrective actions are under review. Refer to project specifc O&M guidance examples in the Appendix. Years 1 & 2: June □ Condition of well to be assessed by qualified hydrogeologist June □ Downhole Video Survey □ Well depth is within 6 inched of as-built depth October □ Provide recommendations if issues are observed October (min. 24: hours after end of rain event) □ Measure water level in UIC Well and UICMH UIC Screen Well & □ Download and replace electronic datalogger (if installed) □ Automated water level measurement Years 1 & 2: Monthly / March □ Less than 2 feet of standing water when no inflow is occurring into MH Maintenance Hole (UICMH) □ Create visual record (hydrograph) of water level fluctuations from datalogger info □ Manual water level measurement October through June September □ No anomalous water level measurements G1 and Underdrain Maintenance □ Report datalogger data and perform and report downhole video survey if more than 2 feet of Holes (UMH) standing water or anomalous water level measurements □ Sediment Accumulation in UICMH & March □ Remove sediment from UICMHs and UMH with hand tools or vactor truck Monthly / October □ Less than one inch of sediment has accumulated in UIC MH and underdrain MH UMH September □ Review bioretention facility as possible source of heavy sediment through June □ Damaged monitoring port, well cap or air March March □ Report if damage is observed □ No damage is observed to monitoring port, well cap or air vent vent September September March March □ Hazards (rodents, contaminants, etc.) □ Report if hazards are observed □ No hazards are observed September September □ Check Observation Port/ Standpipe for standing water and sediment build-up □ Observation Port/ Standpipe has less than 6 inches of standing water within 48 hours following March □ Report standing water for follow up visit March □ Standing water storm event September □ Check for sediment build-up on surface of cell with pit drain September □ No standing water within 24 hours following storm event □ Remove sediment - see A. Facility Footprint G2 Pit Drains & Observation Port March March □ Blockages □ Clear blockages □ Minor blockage at UMHs, cleanouts and underdrain pipes September September □ Check for and report damage to UMH, cleanout or underdrain March □ Damage September □ Minor damage to interior of UMH, cleanout or underdrain pipes □ Video the underdrain if it appears broken/damaged September Year 1: Monthly / September through ○ Standing water in drilled drain - manual Year 1: Monthly / September - May □ Less than 2 feet of standing water 24 hours after storm event □ Remove sediment from drilled drain conveyance pipe May water level measurement □ Less than 6 inches of sediment accumulation in bottom of conveyance pipe. Depth of sediment □ Report if standing water observed and ○ Sediment acculumation in conveyance Year 2 through Service Life: Twice estimated based on depth of conveyance pipe during inspection compared to depth of □ See Major Corrective Maintenance / Long Term Maintenance Table Year 2 through pipe Annually / March and September conveyance pipe post-construction (as measured from rim of structure). Service Life: March and September □ Remove sediment and fouled sand layer(s) from drilled drain with hand tools or vactor Year 1: Monthly September equipment through May □ Sediment accumulation in access □ Replace sand layer(s) to design depth □ Less than 1/8 inch of sediment has accumulated in drilled drain March structure (Reinforced Concrete Pipe) □ Review bioretention facility components as possible source of sediment loading (e.g., □ No standing water in drilled drain structure (above sand layers) when no inflow from Year 2 on: September □ Standing water in access structure cracked cleanout or underdrain pipe) underdrain is occurring March □ If standing water observed, ensure sand replacement alleviates issue. If not, report standing September G3 Drilled Drains water. See Major Corrective Maintenance Table. ○ Damaged access structure ○ Damaged or missing frame or cover March □ Report damage or missing components March □ Minor damage not impacting drilled drain performance ○ Damaged or missing vertical conveyance September □ Repair and replace as necessary September □ No missing components pipe top section, cap, screen, or hose clamps. □ Submit a Drilled Drain Inflow Testing Plan □ Remove sand layers prior to testing □ Report results from drain testing procedure October / □ Compare data from each inflow test with the initial values (established during post- □ Inflow testing October □ The specified capacity of the well has declined by between 1 and 15% Years 1, 2 construction testing), specified capacity, and available head rise □ If target performance standard achieved, replace removed sand layers with new sand. □ Report If target performance standard not achieved. Partial or Full Drilled Drain Rehabilitation may be required.

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\GSI Manual\Vol V - O&M & Inspections\Tables_Checklists\2015-07 SPU_WTD GSI O&M Table Page 6 of 7 SPU/WTD GSI Program Management SPU #C12-004 ESTABLISHMENT PERIOD MAINTENANCE GUIDANCE FOR GSI IN THE RIGHT-OF-WAY Date: July 2015 SvR #12034 OPERATIONS-SUPERVISOR MAINTENANCE-CREW Frequency GSI Facility Observation (Schedule for monthy review; below Component (walk facility-look at conditions that may Maintenance Activity Frequency (Typical) Acceptable are specialized visits that may be trigger maintenance activity) (Targeted Standard) concurrent) H. Permeable Pavement Facility March Pervious Concrete (Full March H1 □ Sediment/ leaf debris/ moss □ Vacuum Sweep both curb lines of entire street and through each intersection October (after leaf □ Minor debris on pavement but not affecting drainage function during rain event Street Length & Width) October (after leaf drop) drop) March Previous Concrete in partial March H2 □ Sediment/ leaf debris/moss □ Vacuum Sweep both curb lines of entire street and through each intersection October (after leaf □ Minor debris on pavement but not affecting drainage function during rain event width or length of street October (after leaf drop) drop) March Pervious Concrete Alley (Full March H3 □ Sediment/ leaf debris/moss □ Vacuum Sweep alley (edge to edge) of entire alley through each intersection October (after leaf □ Minor debris on pavement but not affecting drainage function during rain event or Partial) October (after leaf drop) drop) Fall H4 Pervious Concrete Sidewalk □ Sediment/ leaf debris/moss 1x / year □ Vacuum Sweep/Pressure Wash □ Minor debris on pavement but not affecting drainage function during rain event Spring Areas Adjacent to Porous □ Remove debris, soil that has deposited onto the pavement □ Check if adjacent areas are stabilized. Fall □ Minor soil erosion and moderate debris on pavement but not affecting drainage function during H5 Pavement that drain onto 1x / year □ Vacumn area of impacted permeable pavement No exposed soil. Spring rain event porous □ Mulch and/or plant exposed soils that may erode to pavement surface Maintenance and Repairs □ Cover porous pavement when working on adjacent landscape areas to prevent debris H6 Adjacent to Permeable □ Repairs adjacent to porous pavement _ _ □ Porous pavement is completely covered and protected during repairs accumulation Pavements I. Hardscape/Specialty Elements

March □ Sweep both curb lines of entire street I1 Street Surface □ Road gutter debris Per COS □ Minor road gutter debris on blocks with bioretention facilities September □ Sweep both curb lines for 1 block of intersecting streets upstream of the bioretention facilities

March March Sidewalks □ Moss □ Clean pavement □ Less than 20% of pavement is covered with light moss September September I2 (see also H. Permeable March March □ 10% of pavement is covered with debris, leaves and sediment Pavement) □ Debris, leaves and sediment □ Clean pavement September September □ 4 foot continuous clearance required □ Rake or add mulch to level it out - see E. Mulch □ Weeds in mulch March □ Remove weeds - see D. Vegetation March □ 10% of mulch is uneven or weedy □ Mulch settlement September □ See A. Facility Footprint and E. Mulch for settlement September □ See A. Facility Footprint and E. Mulch for settlement □ See A. Facility Footprint for compacted shoulder at curb and edge of sidewalk □ Rake or add gravel to level it out March March □ 10% of gravel is uneven or weedy □ Remove weeds - see D. Vegetation September September □ See A. Facility Footprint for settlement □ See A. Facility Footprint for settlement □ Weeds in gravel March □ Gravel settlement March □ Add gravel when settlement is 2 inches or less to level with adjacent surface July Paved Paths, Step Out □ Settlement is less than 1 inch I3 September □ See A. Facility Footprint for compacted shoulder at curb and edge of sidewalk September Zones, Curb Edges, Access October March March □ Moss, debris, leaves and sediment □ Clean pavement □ Less than 25% of pavement is covered with moss, debris, leaves and sediment October September

□ Random pavers placed by others □ Report random pavers placed by others March March □ More than 90% pavers are even □ Uneven pavers □ Reset uneven pavers October September □ Less than 20% of paver joints contain weeds □ Spaced Pavers with extensive weeds □ Weed between pavers - see D. Vegetation

□ Report knocked over signs □ Review signs are visible and upright March March □ Signs are visible and upright □ Report inapplicable interperative signs □ Review interpretive signs if applicable October September □ Interpretive signs if applicable □ Prune trees and shrubs for clearance/ visibility I4 Signage and Traffic Markers

□ Review placement of vertical or on edge March March □ Check and report displaced vertical or on edge traffic markers □ Vertical or on edge traffic markers are in place traffic markers at curb bulbs October September

□ Damage Street Furnishings / Public □ Vandalism March □ Report damage or vandalism March I5 □ Furnishings and art are visible, unvandalized or undamaged Art □ Cleanliness October □ Prune trees and shrubs for clearance / visibility September □ Visibility

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GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix C: Major Corrective Action and Long-Term Maintenance Guidance for GSI in the Right- of-Way

GSI Manual, Volume V – Operations & Maintenance Appendix

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SPU/WTD GSI Program Management SPU #C12-004 Date: July 2015 SvR #12034

MAJOR CORRECTIVE ACTION AND LONG-TERM MAINTENANCE GUIDANCE FOR GSI IN THE RIGHT-OF-WAY Notes: 1. The following table is based on the "Guidance Document: Western Washington Low Impact Development (LID) Operation and Maintenance (O&M)" prepared for Ecology Water Quality Program - July 8, 2013 and the 2014 update to City of Seattle's Stormwater Manual. 2. Frequency/Timing/Month shown is for guidance and may be adjusted to site specific conditions. 3. See Examples: Acceptable / Unacceptable Guidance in the appendix of GSI Manual, Volume V. 4. See separate tables for specific guidance for Establishment and Routine Maintenance. 5. See discussion on corrective action and failure or failed systems in GSI Volume V. 6 Orange indicates topic areas that are under development, the guidance included is a placeholder. Refer to project specific O&M guidance in the interim.

OPERATIONS MAINTENANCE PERFORMANCE STANDARD ADDITIONAL INFO

Est. Month Unacceptable Comments GSI Facility Component Observation or Frequency Acceptable Crew Maintenance Activity (Crew) (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Troubleshooting Hours (Targeted Standard) Required)

Major Storm Events (more than 1" rain in 24 hours or wind above 20 mph) □ Before Storm/ Notification of □ Remove at a minimum blockages/leaves from drain curb cuts at Drain Curb Cuts, Catch Storm Event presettling zones, from the curb cut at the first cell after presettling and As directed □ Facility is NOT ready for a storm event: Moderate to □ Facility is ready for a storm event: Minor blockage from Basins (CB), Trench □ Blockage □ After Storm from the curb cut at the low point or corner following weather heavy blockage from debris, sediment or vegetation, debris, sediment or vegetation, minor ponding Drains and Weirs Event □ Remove blockages from all curb cuts if time allows event damaged structures, and/or visible ponding □ After CSO □ Remove blockages from weirs and last CB Notification As directed □ Sand and salt is left on streets and gutter and is □ After snow □ Sweep if sand or salt is used during a snow event and the City does not □ Sand and salt is removed from streets and is not Street Surface □ Sand or salt present following weather allowed to enter bioretention facilities damaging plants storm sweep allowed to enter bioretention facilities event and clogging soils As directed □ After Storm □ Soils appear compressed and ponding observed 24 Swale/Planter Soils □ Water is not draining □ Crew to observe for next 30 days, if problem persists see A1. Soils following weather □ Soils free draining Event hours following rain event Vegetation during □ Extreme drought □ Water □ No watering of bottom area during extreme drought for □ Water vegetation in facility bottom and sloped zone as priority As directed □ Plants surviving (not thriving) during extreme drought Drought □ Water restrictions restrictions over four weeks □ Check pipes, maintenance holes, bioretention swales for settlement, □ Earthquake of Richter Facility after Earthquake _ slumps, cracks, seeps and leakage As directed Magnitude 5.0 or greater □ Report observations and discuss next steps Facility after Car □ Damage to facility caused by □ Check facility, including structures, soil and vegetation, for damage. Accident / Car Enters _ As directed vehicle □ Report observations and discuss next steps for repair Facility A. Facility Footprint □ Repair erosion damage. If gullies are less than 3 inches deep or wide they can be filled with mulch. If greater than 3 inches, fill with bioretention soil, leaving room for 2 to 3 inches of mulch. March and □ Erosion gullies are between 1 inch and 3 inches deep □ Erosion □ Remedy cause - causes may include excessively steep slopes, water As directed □ Erosion gullies are greater than 3 inches deep or wide September or wide velocity, water flow and lack of vegetation cover □ If repeated erosion occurs install rounded cobbles at top of erosion channel without blocking stormwater flow into facility □ Perform maintenance work when soils are dry to prevent compaction □ Soil protection during and damage to soil structure Every visit maintenance □ For extensive maintenance place boards to step on to avoid foot compaction □ Add mulch when settlement is 2 inches or less □ Adjacent to pavement, maintenance holes and at □ Adjacent to pavement, maintenance holes and at A1 Soils □ When settlement is more than 2 inches adjacent to pavement, more crossings: settlement is less than 2 inches crossings: settlement is 2 inches or greater than 4 inches at pipe outfalls and grates, and more than 6 inches at lower □ Adjacent to pipe outfalls and overflow structures: □ Adjacent to pipe outfalls and overflow structures: slopes and bottom areas, remove plants and mulch □ Settlement March As directed settlement is less than 4 inches settlement is 4 inches or greater □ Add soil to 2 inches below adjacent pavement or remaining mulch & replace plants □ Lower slopes and bottom areas: settlement is less than □ Lower slopes and bottom areas: settlement is 6 inches □ Add mulch to the level of adjacent pavement, curbs, or remaining 6 inches or greater mulched areas □ Attempt to identify clogging issue and remedy source of sediment □ Water is not draining 24 hours □ Check cleanouts/ observation ports for standing water after storm and after routine soil □ Remove plants and mulch in areas clogged by sediment remediation performed □ See D. Vegetation below for difficult plants to remove As directed □ Soils free draining □ Ponding water 24 hours after rain event □ Sediment accumulation more □ Remove and replace soil to 6 inches depth than 2 inches □ Add mulch to the level of remaining adjacent mulch □ Do not work soil when saturated

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Est. Month Unacceptable Comments GSI Facility Component Observation or Frequency Acceptable Crew Maintenance Activity (Crew) (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Troubleshooting Hours (Targeted Standard) Required)

A. Facility Footprint (cont.) Earthen side slopes, □ Downstream face of berm □ Fill and compact surrounding soil. □ No visible sign of seeps or saturated zones for □ Side slopes are saturated with many visible seeps or A2 berms and top slope September As directed wet (seeps or leaks) □ Report continued seeps and discuss next steps. extended period more than 3 days leaks. level areas □ There are significantly damaged check dams and □ Repair and remedy undercutting □ There are moderately damaged check dams weirs. □ Failures Note: some check dams may not be needed once cell A3 Check dams September □ Restore failed dams As directed □ There is moderate undercutting. □ There is significant undercutting. □ Undercutting well established (>3 yrs) □ If repair approach is unknown, report and discuss next steps □ Weir is level. □ Check dams appear shifted, not level or seem off from original position □ There are significantly damaged weirs □ Repair and remedy undercutting □ There are moderately damaged weirs □ Failures □ There is significant undercutting. A4 Weirs September □ Restore failed weirs As directed □ There is moderate undercutting. □ Undercutting □ Weirs appear shifted, not level or seem off from □ If repair approach is unknown, report and discuss next steps □ Weir is level. original position □ Walls are secure with minimal damage, gapping, or □ Failures □ Significant damage, gapping, or movement of walls movement of walls □ Leaning walls □ Walls are leaning +/-2 degrees (more than □ Report structurally failing walls (gapping or any movement of walls) and □ Walls are vertical +/-2 degrees (less than approximately □ Gapping at interface with As directed approximately 1/2 inch deflection per foot) discuss next steps for repair or replacement 1/2 inch deflection per foot) Vertical Walls: adjacent concrete □ Gaps at interface with adjacent concrete □ Gaps at interface with adjacent concrete A5 Concrete, Segmental, surfaces/elements September surfaces/elements are greater than 1 inch wide Rockery surfaces/elements are less than 1 inch wide □ Cracking in concrete □ Patch concrete cracks □ Fault or discontinuity at crack or joint is less than 1/2 □ Fault or discontinuity at crack or joint is greater than □ Fault or discontinuity in top of □ Repair fault or discontinuity in top of wall with skim coat or grind concrete September inch 1/2 inch wall for smooth transition □ Check underdrain for standing water and blockages (see Maintenance Holes (MH), Cleanouts and Underdrain Pipes) □ Check drainage structures (CB, Underdrain MH, Underdrain Pipe, UIC MH, etc.) for blockages. May need suction vacuum. See G. Deep Infiltration for blockage of UIC Well and Drill Drain.

□ If underdrain is dry and clear, check for soil compaction and excessive March □ Soil is slightly compacted □ Soil highly compacted A6 Ponded Water □ Water is not draining sedimentation As directed September □ Signs of slower infiltration □ Water is ponding more than 24 hours following rain □ Report source of sediment □ Remove plants - see D. Vegetation below for difficult plants to remove □ Remove sediment plus 2 inches additional soil by hand or with shop vac or other □ Hand till compost into surface or aerate if soil is compacted. □ Reinstall plants and place 1-2 inches mulch □ Do not work soil when saturated

B. Inlets/Outlets/Pipes - Surface Grates, Trash Racks, □ Check for and report damage to grates, trash racks, trench drain grates, March B1 Trench Drain Grates, □ Damaged structures and drain curb cuts As directed □ Minimal damage is observed □ Significant damage is observed September and Drain Curb Cuts □ Report damage and discuss next steps for repair Catch Basins (CBs ) B2 with pipes discharging □ Damaged structures □ Report damage and discuss next steps for repair □ Minimal damage is observed □ Significant damage is observed to swales C. Inlets/Outlets/Pipes - Subsurface

Storm Drains March □ Report damage and discuss next steps for repair □ Minimal damage is observed to pipes and flow is not C1 □ Damaged pipe As directed □ Significant damage is observed to pipes Discharging to Swales September □ Video the pipe interior to review the condition impacted Catch Basins (CBs ) March C2 with pipes discharging □ Damaged structures □ Report damage and discuss next steps for repair □ Minimal damage is observed □ Significant damage is observed September to swales March □ Report damage and discuss next steps for repair C3 Trench Drain □ Damaged structures □ Minimal damage is observed □ Significant damage is observed September □ Video the trench drain interior to review the condition March □ Report damageand discuss next steps for repair C4 Underdrain Clean Outs □ Damaged structures □ Minimal damage is observed □ Significant damage is observed September □ Video the clean out to review the condition □ Repair/seal waterproof liner per manufacturer's requirements when □ Puncture, tear, cracking or □ Damage to liner (punctures, tears, or cracking) greater location is known □ Minimal damage to liner (punctures, tears, or cracking) other degradation of liner than 1 inch measured in longest direction C5 Liners - □ Verify if any seepage issues in the area As directed less than 1 inch measured in longest direction causing leaks into neighboring □ Water is bypassing underdrain system and infiltrating □ If tear location is unknown, discuss next steps. Next steps may include □ Water is entering underdrain system. buildings into soils through puncture flood test to verify and locate puncture. □ Stormwater function March □ Surficial pavement cracking may be indicative of an □ Ponding February □ No issues observed Soil Cells September issue and should be reported C6 □ Algae on edges or surface (Silva Cell ®) □ Observe and report issues such as pavement cracking in the area or March □ Grade breaks or sloughs September □ No issues observed □ Ponding adjacent to soil cell zone settlement September

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Est. Month Unacceptable Comments GSI Facility Component Observation or Frequency Acceptable Crew Maintenance Activity (Crew) (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Troubleshooting Hours (Targeted Standard) Required)

D. Vegetation

□ One or more plant species is crowding out and harming Excessive Vegetation □ Report prior to removal or replacement of vegetation □ There is minor blockage from plants at drain curb cuts, the vitality of other plants □ Plant blockage of inlets, Overgrowth/ Plant March □ Remove selected plants or replace plant species. Replacement species weirs, CB grates, etc. □ Plant growth preventing flow D1 structures, access or sight lines As directed Species Removal or September must meet height restrictions. □ One plant species is spreading more than other plants □ Plant growth over curbs or over pavement by 6 +/- inches □ Excessive overgrowth Replacement □ See below for difficult plants to remove □ Removal of individual plants solves issue □ There is significant blockage from plants at drain curb cuts, weirs, CB grates, etc.

□ Report prior to removal or replacement of vegetation. □ Remove selected plants or replace plant species. □ Replacement species must meet height restrictions. □ Plant mortality March □ More than 25% of plant material is dead. Large groupings □Take note of liner locations to prevent puncturing of liner. Cells with liners As directed □ 25% or less of plant material is dead September of plant species are dead. are designed with specific locations to accommodate trees and large D2 Worn or Dead Plants shrubs □ See below for difficult plants to remove □ Report prior to removal or replacement of vegetation □ Wear due to vehicles or March □ Less than 20% of plants species at high traffic areas are □ More than 20% of plants species at high traffic areas are □ Replace fragile/worn species with more durable species or with arborist As directed pedestrians September impacted by pedestrians or vehicles impacted by pedestrians or vehicles wood chip mulch □ Look for plants to have a color, growth habit and character not typical of their species. Spotting, rust, blackened leaves and other irregularities can be signs of disease. □ Use extreme care not to spread or track any soil or plant material from site of diseased plants to other areas of site □ Clean and disinfect any equipment used to remove, handle, or transport □ Diseased plants As directed any diseased plant material or soil □ Any whole diseased plants and all plant material removed from plants that appear to be diseased should be removed from site and disposed of in March commercial compost or landfill, to avoid risk of spreading the disease to □ More than 25% of plant material is dead. Large groupings of D3 Plant Health □ 25% or less of plant material is diseased or unhealthy September other plants. Pay particular attention to potentially diseased coniferous plant species are dead. trees, especially cypress and cedar.

□ Report multiple dead and dying plants with suspected cause of death □ Review water coverage and condition of irrigation system □ Coordinate removal and replacement of dead and dying plants within 30 □ Unhealthy Plants days □ Replacement vegetation shall be of equal size, conditions, and variety (when appropriate) to original plantings □ Confirm that as-built conditions are appropriate for species planted there

□ Use of herbicides is prohibited without prior approval. Report for approval plans to use of herbicides for stubborn weed infestations. March D4 Weeds □ Weed Infestation □ If weeds cover 70% or more of landscape, cut down weed and plant □ Less than 20% of the vegetation are weeds □ More than 20% of the vegetation are weeds September foliage, cover with cardboard and 3 inches of mulch, and replant the next season □ Trees blocking pedestrian March □ If private tree is overhanging the ROW and blocking pedestrian As directed □ Trees do not block pedestrian movement or sightlines □ Trees block pedestrian movement or sightlines movement or sightlines September movement/access or sightlines notify SDOT □ Maintenance of trees on private property is the howeowners responsibility □ Trees in right of way that are □ If tree is overhanging the ROW and blocking pedestrian □ Trees on private property do not block pedestrian □ Trees on private property block pedestrian movement underoverhanging trees on movement/access or sightlines notify SDOT movement or sightlines or sightlines private property □ Report if tree is overhanging the ROW and interfering with maintenance D5 Trees of facility. Coordination with homeowner is required prior to pruning of trees on private property. □ Prune for clearance as needed to maintain 8 feet at sidewalk and 14 feet Yearly for clearance over road. Prune conifers to have 3-4 feet of clearance at base. □ Street Trees checks and sight □ Prune for visibility if tree is blocking signage or lighting As directed lines □ Structure or form pruning typically at year 5, year 10, year 15 □ Some trees require additional pruning to remove suckers

□ Some species, such as Juncus, may be challenging to remove Plants Difficult to □ Species that are difficult to □ Plants are removed without damaging other □ Problem plants are not able to be removed D6 - □ First, try using a sharp shovel or knife Remove or Dig Up remove for maintenance components □ Plants are removal damages other components □ Power equipment may be required - take care not to puncture lined cells

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Est. Month Unacceptable Comments GSI Facility Component Observation or Frequency Acceptable Crew Maintenance Activity (Crew) (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Troubleshooting Hours (Targeted Standard) Required)

E. Mulch □ Weed area □ Rake out mulch from in between plants small cells to exposed soil □ Do not replace with fresh compost to avoid triggering Clogged /Sediment build □ Weed area again preferably in □ Replaced arborist wood chip mulch improves flushing E1 Mulch 3 to 5 years up/Visibly dirty □ Apply new mulch- arborist wood chips for mature planting early fall permeability. □ Do not replace withor medium or fine grade bark mulch □ For large cells vacumn removal may be utilized with care to protect due to fines tending to hold water from pentrating soil. plants and smaller cobbles or gravel F. Watering

□ Irrigation system is working, a few broken parts. □ Irrigation system is not working. (e.g. coverage is □ Certified irrigation audit Every 3 Years □ Conduct certified irrigation audit Every 3 Years Coverage is slightly uneven. Cap broken equipment or uneven; areas unusually dry or wet; soils washed out) lines and hand water until system is repaired. □ System needs immediate repair.

F1 Irrigation system

□ Adjust controller schedule to reflect the site's exposure, plants' water □ Plants are being overwatered and there is excess plant requirements, planter size, etc. so that plants are neither over nor under- □ Plants are are neither over nor under-watered and are and weed growth □ Watering schedule and rate - watered and are not stressed nor wilted not stressed nor wilted □ Plants are being underwatered and plants are stressed □ Water the plants infrequently but deeply to encourage root growth or wilted

□ If there is no irrigation system, hand water plants twice a week during the dry weather until they are established □ Newly installed plants are watered until they are □ Newly installed plants are not adequately watered and Watering Replacement F2 □ Supplemental watering - □ In drought condition such as no rain for 30 days, established trees and established become stressed, more susceptible to pests and disease Trees and Plants shrubs should be watered deeply (1 inch) a minimum of 1 time per month □ In drought conditions water mature trees and death □ Use tree watering bags for newly planted trees

G. Deep Infiltration (over 6 Feet) - this treatment is new and recommendations for routine O&M procedures and corrective actions are under review. Refer to project specifc O&M guidance examples in the Appendix. March □ Remove sediment from MHs with hand tools or vactor truck This is a placeholder. UIC screen well maintenance is based □ Sediment Accumulation As directed □ Less 1 inch of sediment has accumulated □ More than 1 inch of sediment has accumulated September □ Review bioretention facility as possible source of heavy sediment on WTD's Barton O&M manual. □ Condition of well to be assessed by qualified hydrogeologist. □ Less 2 feet of standing water when no inflow is □ 2 feet or more of standing water when no inflow is September □ Perform video survey before and after cleaning or repair operations September / May have rotating schedule if there are multiple wells. occurring occurring □ Downhole Video Survey Years 5, 10, 15, and □ Report damage such as well screen plugging, filter pack damage, pipe Years 5, 10, 15, (E.g. video wells 1 & 2 during years 3, 8, 13…video □ Well depth is between 1 inch to 6 inch less than as- □ Well depth is more than 6 inches less than as-built 20 corrosion, casing breaks, holes splits and other deformities and 20 wells 3 & 4 in years 4, 9, 14…) built depth depth □ Provide recommendations if issues are observed

UIC screen well O&M is based on WTD's Barton O&M UIC Screen Well & UIC □ Performvideo survey manual. Screen Well □ Qualified personnel to assess condition of well If well does not have electronic dataloggers to track G1 Maintenance Hole (MH) □ If it is determined from review of video & datalogger info (etc.) that inflow October / Years 5, October / Years □ The specific capacity of the well has declined by □ The specific capacity of the well has declined by 15% performance over the past 3-5 years then conduct inflow and Upstream □ Inflow Testing test is needed to assess capacity, conduct UIC well inflow test. 10, 15, and 20 5, 10, 15, and 20 between 1 and 15%. and UIC well screen rehabilitation may be required. test. Maintenance Holes □ Report well testing procedure If well has electronic dataloggers and has data from recent 3 □ Compare data from each inflow test with the initial values, and specific capacity and available head rise. to 5 years then hydrogeologist to review data and determine if inflow test is needed.

□ Downhole video survey of the well screen □ Qualified personnel to assess condition of well screen □ If well screen requires rehabilitation contact well driller for screen October / Year □ Less 2 feet of standing water when no inflow is □ 2 feet or more of standing water when no inflow is This is a placeholder. UIC screen well maintenance is based □ Well Screen Rehabilitation ~ Year 20 rehabilitation 20 occurring infiltration is as expected. occurring infiltration is not as expected on WTD's Barton O&M manual. □ Record rehabilitation techniques □ Flow test following rehabilitation

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Est. Month Unacceptable Comments GSI Facility Component Observation or Frequency Acceptable Crew Maintenance Activity (Crew) (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Troubleshooting Hours (Targeted Standard) Required)

G. Deep Infiltration (over 6 Feet) - this treatment is new and recommendations for routine O&M procedures and corrective actions are under review. Refer to project specifc O&M guidance examples in the Appendix. (cont.)

G2 Pit Drains October and □ Perform downhole video survey October and □ Minimal plugging, pipe corrosion, breaks, holes, splits, ○ Significant plugging, pipe corrosion, breaks, holes, □ Downhole video survey June / Years 5, 10, □ Report damage such as screen pipe plugging, pipe corrosion, breaks, June or other deformities splits, or other deformities 15, and 20 holes, splits, or other deformities □ Submit a Drilled Drain Inflow Testing Plan □ Remove sand layers prior to testing □ Report drain testing procedure □ Compare data from each inflow test with the initial values (established October / Years 5, during post-construction testing), specified capacity, and available head □ The specified capacity of the well has declined by ○ The specified capacity of the well has declined by more □ Inflow testing October 10, 15, & 20 rise. between 1 and 15% than 15%. □ If target performance standard achieved, replace removed sand layers with new sand. □ Report If target performance standard not achieved. Partial or Full Drilled Drain Rehabilitation may be required. G3 Drilled Drains □ Pump water from drilled drain, if necessary □ Perform downhole video survey of screen pipe □ Contact driller for screen pipe rehabilitation ○ Partial Drilled Drain _ □ The specified capacity of the well has declined by □ The specified capacity of the well has declined by more □ Record rehabilitation techniques As directed Rehabilitation between 1 and 15% than 15% □ Perform flow test following rehabilitation □ Report if target performance standard not achieved. Full drilled drain rehabilitation or new drilled drain may be required. □ Remove sand layers, conveyance pipe backfill material, and conveyance pipe □ Replace pipe, backfill material, and sand layers □ Full Drilled Drain _ □ The specified capacity of the well has declined by □ The specified capacity of the well has declined by more □ Flow test following rehabilitation As directed Rehabilitation OR between 1 and 15% than 15% □ Construct new drilled drain □ Report if target performance standard not achieved H. Hardscape □ Repair grade changes with skim coat or shim, or grind concrete for □ There are grade changes or upheaval less than 1 inch. □ There are grade changes or upheavals greater than 1 Paved Pathways and □ Uplifted surface smooth transition H1 September As directed Cracks are less than 1 inch wide. The surface is inch. Cracks are greater than 1 inch wide. The surface is Public Sidewalks □ Cracks □ Patch concrete cracks moderately smooth. very uneven or rough. □ Report if sidewalk section requires replacement I. Pest Control □ Mosquitoes □ No standing water observed in the basin for time periods □ Standing water observed in the basin for time periods July I1 Mosquitoes □ Water is not draining (See □ Report non-draining swales As directed suitable for insect development (designed to drain in 24 suitable for insect development (designed to drain in 24 August Ponded Water) hours) hours) □ Remove all trash, fruit, and nuts that have fallen to the ground to avoid □ Few or no rodent holes are present. □ Nuisance animals March attracting rodents □ Impacted plants are repositioned to avoid repeated □ Nuisance animals are digging holes, causing erosion, I2 Nuisance Animals As directed □ Rodent Holes September □ Fill rodent holes with soil and lightly compact soil around the holes impact/damage damaging plants or depositing large volumes of feces □ Reposition plants away from the holes March □ Remove diseased and dead plants □ A few signs of pests, such as wilting leaves, chewed □ Significant signs of pests, such as wilting leaves, chewed I3 Insect Pests □ Insect pests As directed September □ Follow Integrated Pest Management (IPM) protocols leaves and bark, spotting or other indicators leaves and bark, spotting or other indicators

□ Immediately report spills and any contaminants found in facility areas, pipes and structures (paint, oil, gas, antifreeze, or other spilled/dumped pollutants) □ Block drain curb cuts, drain structures (inlets, outlet, CBs, culverts) to _ prevent spill from flowing into bioretention or onto porous pavements I4 Spill Response □ Spills As directed □ Immediately clean spills associated with work in accordance with SPU's Spill Plan. SPU to assess conditions and determine if full/partial bioretention cell and/or porous pavement replacement is required. □ Record and report the license number If a vehicle is associated with spill.

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Est. Month Unacceptable Comments GSI Facility Component Observation or Frequency Acceptable Crew Maintenance Activity (Crew) (Typical) (Maintenance Trigger-Corrections/Improvements Special Issues Troubleshooting Hours (Targeted Standard) Required)

J. Utility Service Lines _ □ Service line repair by _ □ Provide appropriate information so repairs can be made to like J1 Utility service lines homeowner or other conditions and maintain function. K. Permeable Pavement Facility _ □ Service line repair by □ Provide appropriate information so repairs can be made to like K1 Utility service lines _ homeowner or other conditions and maintain function _ □ Assess condition and determine size of repair to patch □ Pervious concrete: Sawcut panel/portion of panel and replace with pervious concrete □ Pavement is cracked, K2 Pavement Condition 1x year □ Porous asphalt: Sawcut and patch with conventional HMA. Use open □ No significant cracking, spalling. spalling, raveling graded aggregate for subbase (same as in GSI details for porous) □ Take appropriate measures to prevent adjacent porous pavement from becoming clogged during repairs of the pavement Areas Adjacent to □ Check if adjacent areas are □ Remove debris, soil that has deposited onto the pavement K3 Porous Pavement that 1x year stabilized. No exposed soil. □ Mulch and/or plant exposed soils that may erode to pavement surface drain onto porous □ Water is not draining out of underdrain pipe after rain event. □ Assess if underdrain pipe is blocked (video tape or flush pipe to see if it K4 Underdrain pipe Standing water is observed in 1x year will drain) observation port and/or □ Clear blockage in pipe if it is found through videotape inspection underdrain system.

□ Immediately report spills and any contaminants found in facility areas (paint, oil, gas, antifreeze, or other spilled/dumped pollutants) □ Block drain curb cuts, drain structures (inlets, outlet, CBs, culverts) to prevent spill from flowing into bioretention or further onto porous pavements K5 Spill Response □ Spills _ As directed □ Immediately clean spills associated with work in accordance with SPU's Spill Plan. SPU to assess conditions and determine if full/partial porous pavement replacement is required □ Record and report the license number If a vehicle or residence address if it is associated with spill

L. Hardscape/Specialty Elements □ Mulch settlement greater than March March □ See A. Facility Footprint for settlement □ See A. Facility Footprint for soil settlement □ See A. Facility Footprint for soil settlement 2 inches September September Step Out Zones, Curb March L1 □ Remove gravel. Add and compact soil to 2 inches below adjacent Edges, Access □ Gravel settlement greater March July pavement. Replace gravel to 2 inch minimum compacted depth. □ Settlement is between 1 and 2 inches □ Settlement is 2 inches or greater than 2 inches September September □ Maintain design width of compacted shoulder (2 feet min.) October

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GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix D: Images: Routine Maintenance Acceptable / Unacceptable Examples

Images: Routine Maintenance Acceptable / Unacceptable Examples

The purpose of these actual conditions are to give O&M staff a general idea of what conditions to look for in the field and to guide their level of service. This document is intended to be filled in or updated as more examples become available.

Major Storm Events A. Facility Footprint B. Surface - Inlets / Outlets / Pipes / Grates, etc. C. Subsurface - Inlets / Outlets / Pipes, etc. D. Vegetation E. Mulch F. Watering - not included G. Deep Infiltration (over 6 feet) - not included H. Permeable Pavement I. Hardscape MAJOR STORM EVENTS

Acceptable Unacceptable drain curb cut & gutter clear at presettling zone drain curb cut & gutter line blocked with leaf debris at presettling zone

Acceptable Unacceptable light debris at drain curb cuts at first cell past moderate to heavy debris at drain curb cuts at presettling zone and at low point first cell past presettling zone and at low point

Acceptable Unacceptable downstream CB beehive grate is clear overflow CB is significantly blocked

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 2 of 15 A. FACILITY FOOTPRINT

Unacceptable heavy erosion, channelization and scouring with more than 40% bare spots

Acceptable Unacceptable bottom zone plant coverage more than 70% bottom zone plant coverage less than 70% soils Acceptable Unacceptable moderate sediment and water is draining heavy sediment and water is not draining

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 3 of 15 A. FACILITY FOOTPRINT check dams weirs Acceptable Unacceptable weir is clear with little to no undercutting, base is weir blockage (or undercutting with base not exposed exposed) vertical walls

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 4 of 15 A. FACILITY FOOTPRINT boulders, cobbles Acceptable Unacceptable boulders / cobbles in place with little to no boulders / cobbles displaced and / or heavy undercutting or blockage undercutting or blockage (none shown) shoulder & edges Acceptable Unacceptable shoulder has weed cover less than 25%, with shoulder has weed cover more than 25%, with vegetation overhanging shoulder less than 12” vegetation overhanging shoulder more than 12”

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 5 of 15 B. SURFACE - INLETS / OUTLETS / PIPES / GRATES, ETC. drain curb cuts Acceptable Unacceptable minor debris, sediment and blockage at drain heavy debris, sediment and blockage at drain curb cuts along gutter line curb cuts along gutter line trench drain grates trench Acceptable moderate blockage on surface of trench drain grates (none shown) planter walls Acceptable minor damage (none shown) leaves openings heavy damage leaves opening >5” wide <5” wide and / or minor blockage openings and / or heavy blockage along sidewalk

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 6 of 15 B. SURFACE - INLETS / OUTLETS / PIPES / GRATES, ETC.

Acceptable moderate trash, debris and / or sediment at presettling entry or pad zone (none shown) presettling Acceptable minor damage to presettling pad does not impact function grates & trash racks Acceptable Unacceptable moderate blockage at pipe outfalls and CB leaf litter blocking 1/3 of grate at pipe outfalls grates (none shown) and CB grates

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 7 of 15 C. SUBSURFACE - INLETS / OUTLETS / PIPES , ETC. CBs with pipes Acceptable Unacceptable moderate sediment, light blockage and/or heavy sediment, blockage and/or damage to damage to upstream CB pipe trench drains trench Acceptable Unacceptable moderate blockage of trench drain (none heavy plant and sediment blockage of trench shown) drain

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 8 of 15 D. VEGETATION facility bottom Acceptable Unacceptable swale bottom coverage by emergents and swale bottom coverage by live emergents and vegetation is greater than 70% vegetation is less than 70% trash, debris, etc. trash, debris, etc. plant blockage Acceptable Unacceptable minor blockage from plants at drain curb cuts, heavy blockage from plants at drain curb cuts, weirs and CB grates weirs and CB grates

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 9 of 15 D. VEGETATION visibility Acceptable Unacceptable vegetation is slightly over 24” at intersections vegetation is over 24” at intersections and sight and sight clearance zones clearance zones shrub pruning Acceptable Unacceptable small shrubs need minimal pruning shrub pruning is intense and frequently required, shrubs block ped. access & visibility evergreen grasses evergreen Acceptable Unacceptable moderate coverage of adjacent plants and / heavy coverage of adjacent plants and / or or sidewalk by evergreen grass and emergent sidewalk by evergreen grass and emergent foliage foliage

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 10 of 15 D. VEGETATION evergreen grasses evergreen Acceptable Unacceptable evergreen grasses cut back in late winter every evergreen grasses cut back too frequently 2-3 years as needed and die deciduous grasses Acceptable Unacceptable deciduous grasses cut back in late winter deciduous grasses cut back too early (late fall / early winter) and die weeds Unacceptable more than 20% of vegetation are weeds, more than 5% noxious weeds

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 11 of 15 E. MULCH

Acceptable Unacceptable mulch coverage is more than 80%, at least 2” mulch coverage is less than 80%, less than 2” deep and is not blocking structures or inlets deep and / or is blocking structures or inlets

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 12 of 15 H. PERMEABLE PAVEMENT

Acceptable Unacceptable minor amount of soil erosion and / or debris heavy debris and / or eroded soil on pavement deposited onto pavement affecting drainage function during rain event

Acceptable Unacceptable porous pavement is completely covered and porous pavement is not completely covered and protected during repairs protected during repairs or maintenance

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 13 of 15 I. HARDSCAPE / SPECIALTY ELEMENTS street surface street Acceptable Unacceptable moderate road gutter debris on blocks with heavy road gutter debris on blocks with bioretention facilities bioretention facilities sidewalks sidewalks Acceptable Unacceptable less than 40% pavement is covered with moss more than 40% pavement is covered with moss, with thick moss more than 20%

Acceptable Unacceptable less than 20% mulch / gravel is uneven or more than 20% mulch / gravel is uneven or paved paths / step out zones weedy weedy

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 14 of 15 I. HARDSCAPE / SPECIALTY ELEMENTS

Acceptable Unacceptable less than 25% pavement covered with moss, more than 25% pavement covered with moss, paved paths / step out zones debris, leaves and sediment debris, leaves and sediment

Acceptable Unacceptable more than 80% pavers are even and / or less less than 80% pavers are even and / or more than 20% paver joints with extensive weeds than 20% paver joints with extensive weeds signs & traffic markers signs & traffic Acceptable Unacceptable

Routine Maintenance Acceptable / Unacceptable Examples July 2015 page 15 of 15

GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix E: GSI Maintenance Checklists – Examples SPU and WTD

• Barton CSO Control Project GSI Surface Facilities Maintenance Checklist for Establishment, July 2015 • Barton CSO Control Project GSI Storm Drainage System Maintenance Checklist, July 2014 • SPU Checklists TBD

GSI Surface Facilities Maintenance Checklist for Establishment Barton CSO Control Project with GSI

Street Name (btw streets: intersection to intersection): Checked By: Ph: Date of Site Visit: Time of Site Visit :

Date of Last Inspection: As-Built Plan Available Yes □ No □ Does site need maintenance action? (Yes, if Ok □ Action Required □ condition/function Moderate or Low) Weather at time of site visit: Does site need follow-up review upon Ok □ Action Required □ completion of maintenance action (condition moderate or low)? Purpose of visit: □ Routine Maintenance Rain Precipitation (inches) in last 72 hours □ Check swales before rain event (note source for information): Drain Structure Inlets, Grates, Curb Cuts & Weirs HIGH MODERATE LOW □ Facility is ready for a storm event: Minor □ Facility is partially ready for a storm event: □ Facility is NOT ready for a storm event: Comment: blockage from sediment or vegetation, no Moderate blockage from sediment or Heavy blockage from sediment or vegetation, damaged structures, and no ponding. vegetation, some damaged structures, and/or many damaged structures, and/or ponding. some ponding. □ There is minor blockage from plants at □ There is moderate blockage from plants at □ There is heavy blockage from plants at drain Comment: drain curb cuts, weirs, and CB grates. drain curb cuts, weirs, and CB grates. curb cuts, weirs, and CB grates. □ There is minor amount of trash, debris, □ There is moderate trash, debris,fall leaf □ There is heavy amounts of trash, debris, fall Comment: fall leaf litter or sediment at drain curb cuts, litter and sediment at drain curb cuts, weirs, leaf litter and sediment at drain curb cuts, weirs, and CB grates. and CB grates. weirs, and CB grates. □ No damaged drain curb cuts, grates or □ One or two damaged drain curb cuts, □ Several damaged drain curb cuts, grates or Comment: weirs. grates or weirs. weirs. Paved Paths & Sidewalks HIGH MODERATE LOW □ Less than 25% of pavement is covered □ Between 25-40% of pavement is covered □ More than 40% of pavement is covered with Comment: with Moss, debris, leaves and sediment . with Moss, debris, leaves and sediment . Moss, debris, leaves and sediment .

□ There are no grade changes, cracks or □ There are slight grade changes, cracks or □ There are grade changes greater than 1" or Comment: upheaval. The surface is smooth. upheaval. The surface is moderately smooth. significant cracks or upheavals. The surface is uneven or very rough. Bioretention Soils in Swale HIGH MODERATE LOW □ Minor erosion, channelization or scouring □ Moderate erosion, channelization or □ Heavy erosion, channelization or scouring Comment: with less than 25% bare spots. Settlement scouring with less than 40% bare spots. with greater than 40% bare spots. Settlement is less than 1 inch. Settlement is between 1" and 3" inches. is greater than 3 inches. □ Soil is loose, not compacted and water □ Soil is slightly compacted and/or signs of □ Soil highly compacted and water is ponding. Comment: drains within 24 hours and is not ponding. slower infiltration. Spill Prevention and Response, and Pest Control HIGH □ Exercise spill prevention measures whenever handling or storing potential contaminants. Fertilizers, Herbicides, Fungicides and Insecticides Comment: are prohibited in GSI. □ Clean up spills as soon as possible to prevent contamination of stormwater. See O&M Manual and follow Specification 01560, Environmental Management, for spill prevention and response. □ Insects: No standing water observed in the basin for time periods suitable for insect development (designed to drain in 24 hours). Comment: □ Rodents: Few or no rodent holes are present.

Operations and Maintenance Manual - Revised July 23, 2015 Page 1 of 2 GSI Surface Facilities Maintenance Checklist For Establishment Barton CSO Control Project with GSI Vegetation HIGH MODERATE LOW □ Minor amount of trash, pet waste. No □ Moderate amount of trash, pet waste. No □ Heavy amount of trash, pet waste, leaf litter Comment: contaminants. contaminants. and/or downed branches. No contaminants.

□ Little or minor amount of weeds (Less □ Between 15% and 35% of the vegetation □ Great than 35% of the vegetation are weeds. Comment: Estimate percent coverage of than 15% of the vegetation are weeds). No are weeds. Less than 2% noxious weeds Greater than 2% noxious weeds present. Goal representative 10 square foot area. class A, B, C or non-regulated noxious present. Goal is for no noxious weeds. is for no noxious weeds. weeds present. □ Swale bottom coverage by emergents, □ Swale bottom coverage by emergents, □ Swale bottom coverage by emergents, Comment: vegetation and mulch is 90%. vegetation and mulch is between 75% and vegetation and mulch is between 60% and 100%. 75%. □ Mulch covers 100% of the swale side □ Mulch covers at least 70% of the swale □ Mulch covers at least 60% of the swale side Comment: slopes and is approximately 3" to 4" deep. side slopes and is at least 2" deep. slopes or is less than 2" deep.

□ Vegetation at intersection is under 24 □ Vegetation is slightly over 24 inches at □ Vegetation at intersection is over 24 inches. Comment: inches. Vegetation is clear from sidewalk, intersection and slightly over 36 inches along Vegetation overhangs sidewalk, curbs and/or curbs and ramps. Visibility through planter swale. Vegetation partially overhangs ramps. Predominant vegetation along swale is is good. Perennials and grasses are sidewalk, curbs and/or ramps. Visibility is over 36 inches and visibility is impaired trimmed. partially impaired through planter. Perennials through planter. Perennials and grasses are □ Fire hydrant access clearly visible and and grasses are not trimmed. not trimmed. accessible . □ Fire hydrant access clearly visible and □ Fire hydrant access clearly visible and accessible . accessible . □ Pruning: Branches meet clearance over □ Pruning: Branches meet most clearances □ Pruning: Branches do not meet clearance Comment: sidewalk (8') over road (14'). Accent shrubs over sidewalk (8') and road (14'). Accent over sidewalk (8') and road (14'). Accent prunned. shrubs need prunning. shrubs need prunning. □ Plants species are growing well together □ One plant species is overtaking other □ More than one plant species is overtaking Comment: Bare spot is an area of dead or and not blocking drainage. Pruning is easy plants and/or pavement and plants are other plants and/or pavement and plants are missing plants or an area without mulch. and not frequently required. No bare spots. blocking drainage. Pruning for that species is blocking drainage. Pruning is intense and frequently required. Consider removal of frequently required. Consider plant species selective plants. replacement. □ At least 95% of planted vegetation is □ Between 60%-95% of planted vegetation is □ Less than 60% of planted vegetation is Comment: Provide Pictures of Stress or Dead healthy and with a generally good healthy and with a generally good healthy and with a generally good appearance. Plants appearance. Plants are healthy and appearance. Plants exhibit signs of moderate Plants exhibit signs of significant stress, growing, minor amount of wilting, spotting, stress, wilting, spotting or holes in leaves, wilting, spotting or holes in leaves, broken holes in leaves, broken leaders, dead broken leaders, dead wood, suckers or leaders or branches, leaning trees. wood, suckers or branches, trees are branches, leaning trees. plumb. □ Irrigation system is working, no broken □ Irrigation system is working, a few broken □ Irrigation system is not working. Coverage is Comment: Perform annual backflow test. heads, equipment or lines. Coverage is parts. Coverage is slightly uneven. Broken uneven, areas unusally dry or wet. Soils Startup in spring and winterize in the fall. even. equipment or lines to be capped and hand washed out. System needs immediate repair. water until system is repaired. Other Comments or Issues?

Converstions with Home Owners:

Operations and Maintenance Manual - Revised July 23, 2015 Page 2 of 2 GSI Storm Drainage System Maintenance Checklist Barton CSO Control Project

Street Name (btw streets: intersection to intersection): Checked By: Ph: Email: Date of Site Visit: Time of Site Visit : Does site need maintenance action? (Yes, if Ok □ Action Required □ Date of Last Inspection: As-Built Plan Available Yes □ No □ Condition Moderate or Low) Weather at time of site visit: Ok □ Action Required □ Does site need follow-up review upon completion of maintenance action?

Purpose of visit: □ Routine Maintenance □ Check swales after rain event Rain Precipitation (inches) in last 72 hours (note source for information): □ Check swales before rain event □ Other ______

Catch Basins, Drain Curb cuts and Storm Drain Pipes Discharging to Swales HIGH MODERATE LOW □ There is minimal trash, debris and □ There is moderate trash, debris and □ There is significant trash, debris and Comment: sediment at drain curb cuts, weirs, and sediment at drain curb cuts, weirs, and CB sediment at drain curb cuts, weirs, and CB CB grates grates grates □ There is none to minimal blockage at □ There is moderate blockage at drain curb □ There is significant blockage at drain curb Comment: drain curb cuts, weirs, pipe outfalls and cuts, weirs, pipe outfalls and CB grates cuts, weirs, pipe outfalls and CB grates CB grates □ No damage to interior of CB □ Minor damage to interior CB □ Major damage to interior of CB Comment:

Maintenance Holes, Cleanouts and Underdrain Pipes HIGH MODERATE LOW □ There is minimal trash, debris and □ There is moderate trash, debris and □ There is significant trash, debris and Comment: sediment in Underdrain MHs sediment in Underdrain MHs sediment in Underdrain MHs □ There is none to minimal blockage at □ There is moderate blockage at at □ There is significant blockage at at Comment: Underdrain Pipe Underdrain Pipe Underdrain Pipe □ No damage to interior of MH or □ Minor damage to interior of MH or □ Major damage to interior or MH or Comment: Cleanout Cleanout Cleanout

Debris is street upstream of bioretention cells HIGH MODERATE LOW □ No road gutter debris □ Moderate road gutter debris □ Significant road gutter debris Comment:

Other Comments or Issues?

Conversations with Home Owners:

Operations and Maintenance Manual - July 25, 2014 Page 1 of 1

GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix F: GSI Maintenance Work Order Specification – Example WTD

• Barton CSO Control Project Specification Section 02961 – GSI Surface Facilities Maintenance, January 30, 2014 (Update in Progress)

King County WTD Barton CSO Control Project

SECTION 02961

GSI SURFACE FACILITIES MAINTENANCE

PART 1 GENERAL 1.01 PURPOSE A. The primary purpose of the Barton CSO Control Project Facilities is to intercept the stormwater runoff from the street and sidewalks into the bioretention swales for treatment and into the UIC wells for deep infiltration in order to reduce the amount of stormwater flowing into the combined sewer system and causing a CSO event downstream at the Barton pump station. Gutter flow discharges into the bioretention swales via drain curb cuts. Stormwater then filters downward through the bioretention plants and soil for treatment. Once it has been filtered it flows into an underdrain pipe that conveys the flows to a UIC well located in a MH for deep infiltration. 1.02 SUMMARY A. This section specifies maintenance of GSI surface facilities to ensure that the facilities function properly for CSO control. Maintenance of the GSI surface facilities includes the drainage grate collection structures and drain curb cuts, paved pathways and sidewalks, swales, vegetation (landscape), irrigation and other miscellaneous items. B. This is an inclusive specification for GSI landscape maintenance, but not major repairs. C. Do NOT refer to the following specifications: 1. Section 02110 – Site Clearing 2. Section 02200 – Earthwork 3. Section 02270 – Erosion and Sediment Control 4. Section 02900 – Landscaping 5. Section 02910 – Mitigation Landscaping 6. Section 02920 – Landscape Soil Materials 7. Section 02930 – Lawns and Grasses 1.03 REFERENCES A. Referenced Standards: This section incorporates documents by reference. These references are a part of this section as specified and modified. In case of conflict between the requirements of this section and those of a listed document, the requirements of this Section shall prevail. Also see section 01012 – Reference Material. For the work related to the Contract, the latest revision of the following are considered reference documents: B. See Appendix D – Equipment Manuals C. See Appendix E – Draft King County Integrated Pest Management Document 1. Use of pesticides and herbicides is prohibited. 2. This reference covers use of natural landscape practices. D. See Appendix F – GSI Maintenance Reference List for recommended publications, resources and references E. See Appendix H – Project Plans & Link to COS Details F. See Appendix G - Checklists G. Project Record Drawings for SDOT Project No.163005, SDOT Vault Serial No. 774-991. 1.04 DEFINITIONS A. Large Storm Event / Large Storm: 1/2 inch or more rainfall in 24 hours.

Operations and Maintenance Manual GSI SURFACE FACILITIES MAINTENANCE Barton CSO Control Project – January 30, 2014 02961 - 1

GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix G: Planting Guidance for Trees and Vegetation

• ROW Bioretention Cell Planting Zone Diagram, June 15, 2015 • ROW Bioretention Planter Planting Zone Diagram, June 15, 2015 • SPU/WTD GSI Plant and Tree List, June 15, 2015

GSI Manual, Volume V – Operations & Maintenance Appendix

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SYMBOL 4 ZONE 1,2,3 1,2 5 5 4 3 Tree TallShrub Accent Arborist Wood ChipMulch Access Surfacing Access Surfacing Groundcovers &Shrubs PLANT TYPE Low Plantings Emergents, Perennials&LowShrubs Solid Waste Pick-UpSpace (sited forclearancesandout ofliner) Crossing /SidewalkUpper Slope Sidewalk /LowerSwale Along EdgeofCells Step-Out Zones/UpperSlope Crossings /OverflowCurbEdge Sidewalk /UpperSlope Driveway /Intersection Swale Bottom/LowerSlope LOCATION 2 1 2 3 3 5 Sight Clearance/Durable Shade /Water Quality Accent Maintain Edge Optional perContext Access Accent /Border Anchor FUNCTION WaterQuality Treatment 5 PLANT HT. /NOTES 30” max.abovesidewalk 5 20’-50’ -variesbased on powerlinelocation See Chapter8 See Chapter8 See Chapter8 24” max. 4’-8’ +/- 6”-30” ROW BIORETENTION CELL PLANTING ZONEDIAGRAM 5 DECIDUOUS /EVERGREEN Evergreen Mix Mix Mix Mix 2 1 2 3 3 5

SPU/WTD GSI PROGRAM MANAGEMENT SPU# C12-004 June 2015 5 SYMBOL 5 5 ZONE 1A,1B,3 1A,1B 1B 1A 3 5 5 4 3 Medium /Large Tree Small Tree TallShrub Accent PLANT TYPE Arborist Wood ChipMulch Access Surfacing Access Surfacing Low Plantings Groundcovers &Shrubs Low Shrubs,Emergents&Perennials Emergents &Perennials 3 Crossings /SidewalkGrade Planter Bottom Crossing /PlanterBottom Along EdgeofCells Solid Waste Pick-UpSpace Crossings Curb Edge/Step-OutZones Driveway /Intersection Sidewalk Grade Planter Bottom(Edge Areas) Planter Bottom(Center Areas) LOCATION Shade /Water Quality Shade /Water Quality Accent Sight Clearance/Durable Accent /Border Anchor Maintain Edge Optional perContext Steppable WaterQuality Treatment WaterQuality Treatment FUNCTION 5 1A ROW BIORETENTION PLANTER PLANTINGZONE DIAGRAM PLANT HT. /NOTES 30” max.abovesidewalk 30” max.abovesidewalk See Chapter8 See Chapter8 See Chapter8 See Chapter8 See Chapter8 6”-30” max. 24” max. 4’-8’ +/- 1B DECIDUOUS /EVERGREEN Evergreen Deciduous Evergreen 4 Mix Mix Mix Mix

SPU/WTD GSI PROGRAM MANAGEMENT SPU# C12-004 June 2015 FOR INTERNAL DISCUSSION PURPOSES SPU/WTD GSI Program Management SPU #C12-004 Preliminary GSI Plant List Date: June 15, 2015 SvR #12034

GSI Plant List for Development of Palettes Rev. 6-15-2015 Notes: ● Seattle Department of Transportations Right-of Way Improvement Manual establishes height limits for non-street-tree plantings in rights-of-way. Maximum plant height within 30 feet of an intersection (as measured from the corner of the curb) is 24 inches. Elsewhere in the right-of-way, plantings are allowed to be 30 inches with the exception of accent shrubs as directed. ● No plants on the 2011 King County Noxious Weed List, the WA State Noxious Weed Control Board List and the WA State Dept. of Agriculture Prohibited Plant List are to be used. ● "Planting Zone" describes where plants can appropriately be used in bioretention systems. Some trees and shrubs will tolerate saturation. See Planting Zone Codes below. Abbreviations/Legend Operations and Maintenance/ Special Needs Code (O&M Code) Planting Zone Code - See Planting Zone Diagrams EG = Evergreen A= Cut back these perennials to 3" above ground in Fall (October/November) Zone 1 is the designation for plants that are used for water quality in the bottoms of the bioretention facilities. SEMI = Semi-Evergreen B= Leave foliage and seedheads for winter interest and cut back if foliage collapses. Cut DT = Drought Tolerant back in spring (Mid-January to Mid-March) before new growth emerges. Zone 2 is the designation for plants that are used for water quality in the lower slopes / wetted / ponded area of DR = Drought Resistant C= Hand-rake in spring (Mid-January to Mid-March) before new growth emerges. Cut back the bioretention facilities. to ground or thin every 2-3 years as needed. NWN = Northwest Natives or cultivars DS= Deadhead perennials in spring/summer to encourage reblooming and for neater Zone 3 includes species appropriate for planting at the tops and upper slopes of the of bioretention areas that are UF = Urban Frontage (Mixed Use/Commercial) appropriate plants appearance. Deadheading not required for function. used as a border and as accents along the sidewalk, including vertical and accent plants and trees. ☼ = Full Sun DF= Deadhead perennials in fall for neater appearance and to prevent resowing. Zone 4 plants are low, durable plants (under 24") that are used in sight clearance areas or as accents at the edge ∅ = Part Sun/ Part Shade Deadheading not required for function. of the facility. LOS = Level of Service E= Cut back or prune of over sidewalk or clear zones. Remove deadwood anytime fall to Zone 5 is the designation for steppable plants used in the crossing zones and access areas along the curb - spring. these plants may need to tolerate foot traffic, depending on their location. F= May need replacing every 5+/- years. (Replacement not required if vegetation coverage meets requirements) G= May need dividing every few years. Reasons for division include dieback in center and to increase coverage. Part Shade List Guidance Statement: Designer should group plants for maintenance needs to allow ease of pruning and weed control.

Height from Suggested Urban EG DT NWN Scientific Name Common Name Planting Zone Exposure Design Comments O&M Code Additional O & M Comments Ground Size/Spacing Frontage SEMI <24" Abelia x grandiflora 'Prostrata' Prostrate white abelia 3,4 1 Gal./ 30" o.c. UF ☼,∅ E DT 18"-30" Aster divaricatus White wood aster 3 1 Gal./ 24" o.c. ∅ B <24" Carex elata 'Bowles Golden' Bowles Golden sedge 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B EG <24" Carex laxiculmis 'Hobb' Bunny Blue sedge 1,2 10 Cu. In. Plug/ 9" o.c. UF ∅ C Do not intermix with other emergents. Do Can be sheared more frequently if overcrowding EG DT NWN 24"-48"+ Carex obnupta Slough sedge 1,2 10 Cu. In. Plug/ 9" o.c. ☼,∅ C not plant near intersections. other occurs. NWN 24"-36" Carex stipata Beaked sedge 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B Orange New Zealand or Autumn EG 24"-30" Carex testacea or dispacea 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ C Sedge DT 24"-36" Cornus sericea 'Kelseyii' Kelsey redstem dogwood 1,2,3 2 Gal./ 30" o.c. UF ☼,∅ E Stems fragile until established. NWN 24"-40" Deschampsia caespitosa Tufted Hair Grass 1,2 10 Cu. In. Plug/ 9" o.c. ☼,∅ Limit to areas of approx. 36"x36" B LOS A: For neater appearance trim seedheads. <24" Deschampsia flexuosa 'Aurea' Golden crinkled hair grass 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B LOS A: For neater appearance trim seedheads. 24" Fuchsia magellanica 'Aurea' Dwarf Hardy Fuchsia 3,4 2 Gal./ 30" o.c. UF ∅ E 3,4 Prefers part shade. May be short-lived if <24" Galanthus elwesii Giant Snowdrop Bulb UF ☼,∅ F too hot. If height is a problem, Salal can be sheared with EG DT NWN 24"-36"+ Gaultheria shallon Salal 3 1 Gal./ 24" o.c. UF ☼,∅ E hedge trimmer. EG <24" Geum flore-plena 'Blazing Sunset' Blazing Sunset Avens 3,4 1 Gal./ 10" o.c. UF ☼,∅ DS 24"-36" Iris pallida 'Variegata' Variegated sweet iris 3 1 Gal./ 18" o.c. UF ☼,∅ A EG DR NWN <24" Mahonia repens Creeping Oregon holly-grape 3,4 1 Gal./ 18" o.c. UF ☼,∅ E EG DR NWN 24"-36" Polystichum munitum Western swordfern 3 2 Gal./ 24" o.c. UF ∅ Limit to group of 3 B Cut back before fronds appear. EG DT 24"-36" Prunus laurocerasus 'Mount Vernon' Mount Vernon cherry laurel 3 2 Gal./ 24" o.c. UF ☼,∅ E Rhododendron Yak Hybrids, such as 'Ken Several other Yak hybrids stay low and LOS A: May produce more flowers if pruned and/or EG 36" Yak Hybrid 3 2 Gal./ 24" o.c. UF ☼,∅ E Janeck' neat deadheaded after blooming EG DT <24" Sarcococca hookeriana humilis Himalayan Sweet Box 3 2 Gal./ 24" o.c. UF ∅ Winter fragrance E EG 30" Taxus 'Emerald Spreader' Emerald Spreader Yew 3 2 Gal./ 24" o.c. UF ☼,∅ E NWN <24" Tolmiea menziesii Youth on Age 1,2,3 1 Gal./ 10" o.c. ∅ G EG DT <24" Veronica liwanensis Speedwell 3,4,5 4" Pot/ 12" o.c. UF ☼,∅ E LOS A: Cut back for neater apperance.

F:\12\12034 SPU GSI PM\Task 2-Tech Analysis&Support\subjectmatter memos\4p-Planting elements\SPU WTD GSI Plant Lists -6-2015 Page 1of 12 FOR INTERNAL DISCUSSION PURPOSES SPU/WTD GSI Program Management SPU #C12-004 Preliminary GSI Plant List Date: June 15, 2015 SvR #12034

GSI Plant List for Development of Palettes Rev. 6-15-2015 Sun List Guidance Statement: Designer should group plants for maintenance needs to allow ease of pruning and weed control.. Bulbs and perennials that are tough, long-lived and minimal maintenance can be added at designer's discretion. Height from Urban EG DT NWN Scientific Name Common Name Planting Zone Size/Spacing Exposure Design Comments O&M Code Additional O & M Comments Ground frontage SEMI <24" Abelia x grandiflora 'Prostrata' Prostrate white abelia 3,4 1 Gal./ 30" o.c. UF ☼,∅ E DT <24" Aster novi-belgii 'Wood's Blue' Wood's Blue New York Aster 3 1 Gal./ 18" o.c. UF ☼ B, G 24"-36" Carex muskingumensis Palm sedge 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B 24"-36" Carex elata 'Bowles Golden' Bowles Golden Sedge 1,2,3 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B 24"-36"+ Carex grayi Gray's sedge 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B NWN 24"-36" Carex stipata Beaked sedge 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B EG 24"-30" Carex testacea or dispacea Orange New Zealand or Autumn 1,2,3 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ C Cut back to about 18" above the ground or by half in DT 24"-36" Caryopteris incana 'Sunshine Blue' Sunshine Blue Bluebeard 3,4 1 Gal./ 18" o.c. UF ☼ B OR DF early spring after new leaves are visible DT NWN 24"-30" Cornus sericea 'Kelseyii' Kelsey redstem dogwood 1,2,3 2 Gal./ 30" o.c. UF ☼,∅ E Stems fragile until established. NWN 24"-40" Deschampsia caespitosa Tufted Hair Grass 1,2 10 Cu. In. Plug/ 9" o.c. ☼,∅ Limit to areas of approx. 36"x36" B LOS A: For neater appearance trim seedheads. <24" Deschampsia flexuosa 'Aurea' Golden crinkled hair grass 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B LOS A: For neater appearance trim seedheads. DT 24"-36" Echinacea purpurea Coneflower 3 1 Gal./ 18" o.c. UF ☼ B LOS A: For neater apperance deadhead. If height is a problem, Salal can be sheared with EG DT NWN 24"-36"+ Gaultheria shallon Salal 3 1 Gal./ 24" o.c. UF ☼,∅ E hedge trimmer. EG DT 24"-36" Hebe 'Red Edge' Red Edge Hebe 3,4 1 Gal./ 24" o.c. ☼ E Later flowering varieties are not as DT <24" Hemerocallis - Later Flowering Varieties Later Flowering Daylily varieties 3,4 1 Gal./ 15" o.c. UF ☼,∅ A LOS A: For neater apperance deadhead. susceptible to Daylily gall midge. EG DT <24" Geranium x cantabrigiense 'Cambridge' Perennial Geranium 3,4 1 Gal./ 15" o.c. UF ☼,∅ B SEMI DT <24" Helianthemum 'Henfield Brilliant' Sunrose 3,4 1 Gal./ 10" o.c. UF ☼ B EG DT 24"-36" Helictotrichon sempervirens Blue oat grass 3 1 Gal./ 18" o.c. UF ☼ C EG DT <24" Ilex x 'Mondo' Little Rascal Holly 3,4 1 Gal./ 18" o.c. UF ☼,∅ E LOS A: For neater appearance cut back dead leaves EG DT NWN <24" Iris douglasiana Pacific Coast Iris 3,4 1 Gal./ 18" o.c. UF ☼ Many colors available. G and flower stalks. LOS A: For neater appearance cut back dead leaves SEMI DT NWN <24" Iris missouriensis Rocky Mountain Iris 1,2 1 Gal./ 12" o.c. UF ☼ G and flower stalks. LOS A: For neater appearance cut back dead leaves 24"-36" Iris sibirica cultivars such as 'Bennerup Blue' Siberian Iris 1,2,3 1 Gal./ 18" o.c. UF G and flower stalks. LOS A: Can be sheared more frequently if foliage EG DT NWN <24" Juncus balticus Baltic rush 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼ C collapses. LOS A: Can be sheared more frequently if foliage EG NWN 24"-36" Juncus effusus 'Quartz Creek' Quartz Creek Soft Rush 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ C collapses. EG DT <24" Juniperus conferta 'Blue Pacific' Blue Pacific Shore juniper 3,4 1 Gal./ 3' o.c. UF ☼ E DT NWN 36" Leersia oryzoides Rice Cutgrass 1,2 10 Cu. In. Plug/ 9" o.c. ☼ Limit to areas of approx. 36"x36" B LOS A: For neater appearance trim seedheads. EG DR NWN <24" Mahonia repens Creeping Oregon holly-grape 3,4 1 Gal./ 18" o.c. UF ☼,∅ E DR 36" Miscanthus sinensis 'Little Kitten' Little Kitten Maiden Grass 3 1 Gal./15" o.c. UF ☼ B DT 30" Nepetax 'Walker's Low' Catmint 3 1 Gal./ 18" o.c. UF ☼,∅ B Rhododendron Yak Hybrids, such as 'Ken Several other Yak hybrids stay low and LOS A: May produce more flowers if pruned and/or EG 36" Yak Hybrid 3,4 2 Gal./ 30" o.c. UF ☼,∅ E Janeck' neat deadheaded after blooming DT 24"-36" Rudbeckia fulgida ' Goldsturm' Black-Eyed Susan 3,4 1 Gal./ 18" o.c. UF ☼ Late season color accent. A OR B LOS A: Can be cut back by half in June to prevent DT <24" Sedum ' Autumn Joy' or 'Matrona' Stonecrop 3,4 1 Gal./ 12" o.c. UF ☼ G flopping. Solidago canadensis 'Baby Gold' or Baby Gold or Little Lemon DT NWN <24" 3,4 1 Gal./ 18" o.c. ☼ Late season color accent. A Solidago hybrida 'Dansolitlem' Goldenrod NWN 24"-48" Spiraea betulifolia or Spiraea betulifolia 'Tor' Birchleaf spirea 3 1 Gal./ 24" o.c. UF ☼ E EG DT NWN <24" Sedum oreganum Stonecrop 3,4,5 4" Pot/ 12" o.c. UF ☼ Tolerates hot dry sites. E LOS A: For neater appearance trim spent flowers in EG DT <24" Teucrium chamaedrys Wall germander 3,4 1 Gal./ 18" o.c. UF ☼ E spring. EG DT <24" Thymus serpyllum 'Elfin' Elfin creeping thyme 3,4,5 4" Pot/ 12" o.c. UF ☼ F

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GSI Plant List for Development of Palettes Rev. 6-15-2015 Native List (Sun to Part Shade includes cultivars) Guidance Statement: Designer should group plants for maintenance needs to allow ease of pruning and weed control. Plants over 24/30 inches mature height to be located in downslope conditions unless used as accent shrub to assist in staying at 24/30 inch height. Native bulbs and perennials that are tough, long-lived and minimal maintenance can be added at designer's discretion.

Height from Urban EG DT NWN Scientific Name Common Name Planting Zone Size/Spacing Exposure Design Comments O&M Code Additional O & M Comments Ground frontage DR NWN 24"-36" Aquilegia formosa Western Columbine 3,4 1 Gal./ 18" o.c. ☼,∅ DF Possible use at vertical wall or single use Arctostaphylos uva-ursi 'Massachusetts' or EG DT NWN <24" Kinnickinnick 3,4 1 Gal./ 12" o.c. UF ☼,∅ low accent. Requires approval by Project E 'Pt. Reyes' Manager and Maintenance prior to use. Great Camus or Common Plant for in groups for effect. Can be DR NWN 24"-36" Camus leichtlinii or Camus quamash 3,4 1 Gal./ 12" o.c. ☼,∅ DF Camus planted as a bulb EG NWN 30" Carex densa Dense sedge 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼ C DR NWN 24"-48" Carex deweyana Dewey's sedge 1,2 10 Cu. In. Plug/ 9" o.c. ☼,∅ Limit to areas of approx. 36"x36" B Do not intermix with other emergents. Do Can be sheared more frequently if overcrowding EG DT NWN 24"-48"+ Carex obnupta Slough sedge 1,2 10 Cu. In. Plug/ 9" o.c. ☼,∅ C not plant near intersections other occurs. DT NWN 24"-36" Carex pachystachya Chamisso sedge 1,2 10 Cu. In. Plug/ 9" o.c. ☼,∅ Limit to areas of approx. 36"x36" B NWN 24"-36" Carex stipata Beaked sedge 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B DT NWN 24"-30" Cornus sericea 'Kelseyii' Kelsey redstem dogwood 1,2,3 2 Gal./ 30" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" E Stems fragile until established. NWN 24"-40" Deschampsia caespitosa Tufted Hair Grass 1,2 10 Cu. In. Plug/ 9" o.c. ☼,∅ Limit to areas of approx. 36"x36" B LOS A: For neater appearance trim seedheads. DT NWN <24" Erigeron peregrinus subalpine fleabane daisy 3,4 1 Gal./ 12" o.c. UF ☼ DF DT NWN 36" Festuca idahoensis Idaho fescue 3,4 1 Gal./ 18" o.c. ☼ DF If Gaultheria shallon is substituted see If height is a problem, can be sheared with hedge EG DT NWN <24" Gaultheria ovatifolia Oregon wintergreen 3,4 1 Gal./ 24" o.c. UF ☼,∅ E additional O&M notes trimmer. LOS A: For neater appearance cut back dead leaves EG DT NWN <24" Iris douglasiana Pacific Coast Iris 3,4 1 Gal./ 18" o.c. UF ☼ Many colors available. G and flower stalks. LOS A: For neater appearance cut back dead leaves SEMI DT NWN <24" Iris missouriensis Rocky Mountain Iris 1,2 1 Gal./ 12" o.c. UF ☼ G and flower stalks. LOS A: Can be sheared more frequently if foliage EG DT NWN <24" Juncus balticus Baltic rush 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼ C collapses. Do not intermix with other emergents. Do EG DT NWN 24"-48"+ Juncus effusus Common rush 1,2 10 Cu. In. Plug/ 9" o.c. ☼,∅ C not plant near intersections EG NWN <24" Juncus ensifolius Dagger-leaf rush 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Limit to areas of approx. 36"x36" B EG DT NWN <24" Juncus tenuis Path rush 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ C EG DT NWN <24" Juniperus communis 'Mondap' Alpine carpet juniper 4 1 Gal./ 24" o.c. UF ☼ E May require prunning EG NWN 36" Ledum glandulosum Pacific or trapper's tea 1,2,3 5 Gal./ 36" o.c. UF ☼,∅ Plant near the bottom of swale E DT NWN 36" Leersia oryzoides Rice Cutgrass 1,2 10 Cu. In. Plug/ 9" o.c. ☼ Limit to areas of approx. 36"x36" B LOS A: For neater appearance trim seedheads. EG DT NWN <24" Lewisia cotyledon or cultivars Siskiyou lewisia 3,4 1 Gal./ 12" o.c. UF ☼ E Mahonia aquifolium 'Orange Flame' or EG NWN 36" Compact tall Oregon grape 3 1 Gal./36" o.c. UF ☼,∅ E 'Compacta' EG DR NWN <24" Mahonia repens Creeping Oregon grape 3,4 1 Gal./ 18" o.c. UF ☼,∅ E DT NWN <24" Maianthemum dilatatum False Lily of the Valley 1,2,3,4 4" Pot/ 12" o.c. UF ∅ Note tendency to spread E LOS A: Remove dead foliage in fall. NWN 24"-36" Mimulus guttatus Yellow monkey-flower 1,2 1 Gal./ 18" o.c. ☼,∅ DF EG DT NWN 36" Pachistima myrsinites Oregon Boxwood 3 1 Gal./36" o.c. UF ☼,∅ E NWN <24" Potentilla fruticosa 'Sunset' Frosty potentilla 3,4 2 Gal./ 30" o.c. UF ∅ E Sticky cinquefoil or slender DT NWN <24" Potentilla glandulosa or Potentilla gracilis 3,4 1 Gal./ 18" o.c. ☼,∅ DF cinquefoil Polystichum imbricans or Polystichum Narrow-leaf sword fern or If Polystichum munitum is substituted limit EG NWN 24"-36" 3,4 2 Gal./ 30" o.c. UF ☼,∅ B Cut back before fronds appear. lonchitis Northern holly fern groups to 3 and prune yearly Solidago canadensis 'Baby Gold' or Baby Gold or Little Lemon DT NWN <24" 3,4 1 Gal./ 18" o.c. ☼ Late season color accent. A Solidago hybrida 'Dansolitlem' Goldenrod NWN 24"-36" Spiraea betulifolia or Spiraea betulifolia 'Tor' Birchleaf spirea 3 1 Gal./ 24" o.c. UF ☼ E

EG DT NWN <24" Sedum divergens Stonecrop 3,4 4" Pot/ 12" o.c. UF ☼,∅ Tolerates hot dry sites. E LOS A: For neater apperance deadhead.

EG DT NWN <24" Sedum oreganum Stonecrop 3,4,5 4" Pot/ 12" o.c. UF ☼ Tolerates hot dry sites. E EG DT NWN 24"-36" Xerophyllum tenax Bear grass 3 1 Gal/ 18" o.c. UF ☼ Tolerates hot dry sites. E

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GSI Plant List for Development of Palettes Rev. 6-15-2015 Intersection & View Restriction Palette (Under 24" Ht.) Guidance Statement: Maximum plant height within 30 feet of an intersection (as measured from the corner of the curb) is 24 inches. Elsewhere in the right-of-way, plantings are allowed to be 30 inches tall. Careful placement in the sightline or view restriction zones so grass stems are transparent; depending on plant a group of three may be the maximum number to maintain open sightlines. Designer should group plants for maintenance needs to allow ease of pruning and weed control.

Height from Urban EG DT NWN Scientific Name Common Name Planting Zone Size/Spacing Exposure Design Comments O&M Code Additional O & M Comments Ground frontage Chrysanthemum 'Peach Centerpiece' or Peach Centerpiece or golden <24" 3,4 1 Gal./ 15" o.c. ☼ Late season color accent. B & G Pull if scraggly. 'Bienchen' Chrysanthemum DT <24" Coreopsis lanceolata 'Sterntaler' Tickseed 3,4 1 Gal./ 15" o.c. UF ☼ B & G DT 24"-30" Cornus sericea 'Kelseyii' Kelsey redstem dogwood 1,2,3 1 Gal./ 30" o.c. UF ☼,∅ Plant in bottom areas for sightlines. E Stems fragile until established. EG DT <24" Epimedium rubrum or sulphurescens Barrenwort 3,4 4" Pot/ 12" o.c. UF ∅ Part shade to shade only without irrigation. B Cut back before flower stalks appear. EG DT <24" Euonymus fortunei ' Interbolwi' Blondy wintercreeper 3,4 1 Gal./ 18" o.c. UF ☼,∅ E DT <24" Geranium ' Gerwat' Rozanne Rozanne geranium 3,4 1 Gal./ 24" o.c. ☼,∅ A LOS A: Can be sheared for neater appearance. EG <24" Geum flore pleno 'Blazing Sunset' Blazing Sunset Avens 3,4 1 Gal./ 18" o.c. UF ☼,∅ DS EG <24" Hebe x ' Champion' Champion Hebe 3,4 1 Gal./ 18" o.c. UF ☼,∅ E Helianthemum nummularium 'Wisley 1 Gal./ 12" o.c. SEMI DT <24" Yellow Sunrose 3,4 UF ∅ B Primrose' 36" height only when in flower. Airy EG DT 24"-36" Helictotrichon sempervirens Blue oat grass 3 1 Gal./ 18" o.c. UF ∅ C flowers. Groups of 3 maximum. EG DT <24" Ilex x 'Mondo' Little Rascal Holly 3,4 1 Gal./ 18" o.c. UF ☼,∅ E EG NWN <24" Juncus effusus 'Carmen's Japan' Carmen's Japanese Rush 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ C LOS A: Can be sheared more frequently if foliage EG <24" Juncus effusus 'Spiralis' Corkscrew soft rush 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ C collapses. LOS A: Can be sheared more frequently if foliage EG 24"-30" Juncus patens or Juncus patens 'Elk blue' California gray rush 1,2 10 Cu. In. Plug/ 9" o.c. UF ☼,∅ Plant in bottom areas for sightlines C collapses. EG <24" Liriope muscari and cultivars Lily Turf 3,4 4" Pot/ 12" o.c. UF ☼,∅ C OK to pull clumps for ease of weed control. EG DR NWN <24" Mahonia repens Creeping Oregon holly-grape 3 1 Gal./ 18" o.c. UF ☼,∅ E DT <24" Narcissus ‘Dutch Master’ or ' King Alfred' Daffodil 3,4 Bulb/ As Shown UF ∅ DS Cut back foliage in summer. NWN <24" Potentilla fruticosa 'Sunset' Frosty potentilla 3,4 2 Gal./ 30" o.c. UF ∅ E EG DT <24" Veronica liwanensis Speedwell 3,4,5 4" Pot/ 12" o.c. UF ∅ E LOS A: Cut back for neater apperance.

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GSI Plant List for Development of Palettes Rev. 6-15-2015 Vertical Shrubs & Accent Plants Guidance Statement: Generally single accent plant however no more than 3 accent plants in a group to preserve sight lines. Prefer large sizes to start.

Height from Urban EG DT NWN Scientific Name Common Name Planting Zone Size/Spacing Exposure Design Comments O&M Code Additional O & M Comments Ground frontage

NWN 25' Amelanchier alnifolia Service Berry 1,2,3 Multi-stem, B&B, 5'-6' ht. ∅ Multi-stems are common. E May need windowing/ thinning. Prune 2/3 of all (older) branches to 8" above ground 5' Cornus sanguinea 'Midwinter Fire' Midwinter Fire Dogwood 1,2,3 5 gal ☼,∅ E in March to keep in bounds & to maintain yellow twigs. Prune 2/3 of all (older) branches to 8" above ground NWN 6' to 8' Cornus sericea 'Flaviramea' Yellow-Twig Dogwood 1,2,3 5 gal ∅ E in March to keep in bounds & to maintain red twigs. 10' Hamamelis x intermedia 'Pallida' Witch Hazel 3 10 gal ☼,∅ Vase-shaped open growing form E Late summer flowers. Fall color. Bold 5' Hydrangea quercifolia 'Pee Wee' Oak-Leaf Hydrangea 3 5 gal ∅ E May need windowing/ thinning. leaves in winter. Female plants need a male pollinator to produce EG 3'-4' Ilex glabra 'Shamrock' Inkberry 1,2 5 gal. ☼,∅ E berries. Female plants need a male pollinator to produce 3'-12' Ilex verticillata & cultivated varieties Winterberry 1,2 5 gal. ☼,∅ E berries. EG 8' - 12' Mahonia 'Arthur Menzies' Ornamental Mahonia 3 5 gal ☼,∅ Upright multi-stemmed. E EG NWN 6'-10' Mahonia aquifolium Oregon grape 3 5 gal ☼,∅ Upright multi-stemmed. E 4' wide. Considered dwarf. New foliage is EG 5' Osmanthus 'Goshiki' Variegated Osmanthus 3 5 gal ∅ E May need windowing/ thinning. colorful. 6' Physocarpus opulifolius 'Nanus' Dwarf Ninebark 1,2,3 5 gal ☼,∅ Even dwarf form may be tall & wide. E May need windowing/ thinning. Variegated foliage that emerges pink in EG 4' Pieris japonica 'Little Heath' Little Heath Lily of the Valley 3 3 gal. ∅ E May need windowing/ thinning. spring. Flowers in winter NWN 8' Ribes sanguineum & cultivated varieties Red Flowering Currant 3 5 gal ∅ Attracts hummingbirds E May need windowing/ thinning. Specify tree form; Prune to ground every other year 15'-20' Salix integra 'Hakuro Nishiki' Dappled Willow 1,2,3 5 gal. ☼,∅ E to keep smaller 8'-15' Sambucus nigra 'Gerda' Black Beauty Black Elder 1,2,3 5 gal. ☼,∅ E NWN 6' Symphoricarpos albus Snowberry 1,2,3 5 gal ☼,∅ Forms thickets. E May need windowing/ thinning. 6' Taxodium distichum 'Peve Minaret' Dwarf bald cypress 1,2,3 E EG NWN 6' Vaccinium ovatum Evergreen Huckleberry 1,2,3 5 gal ☼,∅ E Self-pollinating edible fruits. Good fall 6' Vaccinium 'Sunshine Blue' Blueberry 3 5 gal ☼,∅ E color. EG 10' Viburnum cinnamomifolium Cinnamon Viburnum 3 10 gal ☼,∅ E May need windowing/ thinning. NWN 7'-12' Viburnum edule Highbush cranberry 1,2,3 5 gal. ☼,∅ E

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GSI Plant List for Development of Palettes Rev. 6-15-2015 Groundcovers if Low Profile is Required Guidance Statement: Do not mix groundcovers - plant in groups of 9 to 12 minimum. Height from Urban EG DT NWN Scientific Name Common Name Planting Zone Size/Spacing Exposure Design Comments O&M Code Additional O & M Comments Ground frontage

EG DT <24" Ajuga reptens Bugleweed 3,4 4" Pot/ 12" o.c. UF ☼,∅ E Can be pulled if grows beyond desired boundaries. Epimedium rubrum or sulphurescens or EG DT <24" Barrenwort 3,4 4" Pot/ 12" o.c. UF ∅ B Cut back foliage before flower stalks appear. cultivars EG DT <24" Euonymus fortunei 'Kewensis' Wintercreeper euonymous 3,4 1 Gal./ 18" o.c. UF ☼,∅ E Can be mowed to keep low. Geranium macrorrhizum ' Album' or other SEMI DT <24" Hardy Geranium 3,4 1 Gal./ 18" o.c. UF ☼,∅ B cultivars DT NWN <24" Maianthemum dilatatum False Lily of the Valley 1,2,3,4 4" Pot/ 12" o.c. UF ∅ Note tendency to spread E LOS A: Remove dead foliage in fall. EG DT <24" Pachysandra terminalis Japanese Spurge 3,4 4" Pot/ 12" o.c. UF ∅ C Sibbaldiopsis tridentata (=Potentilla EG DT <24" Three-toothed Cinquefoil 3,4 4" Pot/ 12" o.c. UF ∅ E tridentata) Tolerates deep shade. Not as aggressive EG DT <24" Rubus tricolor Creeping Chinese Bramble 3,4 4" Pot/ 12" o.c. UF ∅ or spiny as other Rubus groundcovers. E Red fuzzy stems & shiny leaves.

EG DT NWN <24" Sedum divergens Stonecrop 3,4 4" Pot/ 12" o.c. UF ☼,∅ Tolerates hot dry sites. E LOS A: For neater apperance deadhead.

EG DT <24" Sedum requieni Miniature Stonecrop 3,4,5 4" Pot/ 12" o.c. UF ☼,∅ Tolerates hot dry sites. E DT NWN <24" Vancouveria hexandra Inside Out Flower 3,4 4" Pot/ 12" o.c. UF ∅ E SEMI <24" Potentilla neumanniana 'Nana' Dwarf cinquefoil 3,4,5 4" Pot/ 12" o.c. UF ☼,∅ E EG <24" Ophiopogon japonicus 'Nanus' Dwarf mondo grass 3,4,5 4" Pot/ 12" o.c. UF ☼,∅ Can space at 15" o.c. for cost saving E

Steppable Plants Guidance Statement: The following are plants that can tolerate some foot traffic. Height from Urban EG DT NWN Scientific Name Common Name Planting Zone Size/Spacing Exposure Design Comments O&M Code Additional O & M Comments Ground frontage EG <24" Ophiopogon japonicus 'Nanus' Dwarf mondo grass 3,4,5 4" Pot/ 12" o.c. UF ☼,∅ Can space at 15" o.c. for cost saving E SEMI <24" Potentilla neumanniana 'Nana' Dwarf cinquefoil 3,4,5 4" Pot/ 12" o.c. UF ☼,∅ E EG DT NWN <24" Sedum oreganum Stonecrop 3,4,5 4" Pot/ 12" o.c. UF ☼ Tolerates hot dry sites. E EG DT <24" Sedum requieni Miniature Stonecrop 3,4,5 4" Pot/ 12" o.c. UF ☼,∅ Tolerates hot dry sites. E EG DT <24" Thymus serpyllum 'Elfin' Elfin creeping thyme 3,4,5 4" Pot/ 12" o.c. UF ☼ F EG DT <24" Veronica liwanensis Speedwell 3,4,5 4" Pot/ 12" o.c. UF ∅ E LOS A: Cut back for neater apperance.

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GSI Tree Lists Rev. 6-15-2015 Notes: ● This tree list has been adapted from the SDOT Street Tree List, with trees added and removed for conditions of bioretention. ● No plants on the 2011 King County Noxious Weed List, the WA State Noxious Weed Control Board List and the WA State Dept. of Ag Prohibited Plant List are to be used. ● Designers should review each neighborhood for tree species diversity and select species to provide variety. ● See figure G1-G3 "Strategies for Trees along Bioretention Cells". ● O&M = Operations and Maintenance Planting Zone Code Zone 1 is the designation for plants that are used for Zone 3 includes species appropriate for planting at the tops and Zone 5 is the designation for plants used in the crossing water quality in the bottom of the bioretention upper slopes of the of bioretention areas that are used as a border zones and access areas along the curb - these plants facilities. and as accents along the sidewalk, including vertical and accent may need to tolerate foot traffic, depending on their plants and trees. location. Zone 2 is the designation for plants that are used for Zone 4 plants are low, durable plants (under 24") that are used in water quality in the lower slopes / wetted / ponded sight clearance areas or as accents at the edge of the facility. area of the bioretention facilities. Conifers (Deciduous & Evergreen) Guidance Statement: Plant larger sizes in order to be able to limb them up to 36" minimum clearance. General O&M Statement: Prune up yearly until sight clearance achieved. Mature Under Min Strip Planting Fall SDOT Scientific & Common Name Urban Spread Design Comments Wires? Width Zone Color List Height Calocedrus decurrens, 75 15 No 8 3 Incense Cedar Metasequoia glyptostroboides 50 25 No 6 1,2,3 Yes Fast growing deciduous conifer. Dawn Redwood Pinus contorta contorta 45 30 No 5 1,2,3 Shore Pine Taxodium distichum A deciduous conifer, broadly spreading when mature – 55 35 No 8 1,2,3 Yes Bald Cypress columnar when young. Taxodium distichum 'Mickelson' 55 20 No 6 1,2,3 Yes x Deciduous conifer - tolerates city conditions Shawnee Brave Bald Cypress Thuja plicata 'Excelsa' or 'Hogan' 40 15-20 No 8 1,2,3 Narrow columnar form. Western Red Cedar

Medium/Large Broad-Leaved Evergreen Trees Guidance Statement: Ornamental in appearance, provides year-round function. General O&M Statement: Prune up yearly until sight clearance achieved. Mature Under Min Strip Planting Fall SDOT Scientific & Common Name Spread Design Comments Height Wires? Width Zone Color List Lithocarpus densiflorus 50 20 No 6 3 Tanoak Quercus Ilex Underside of leaf is silvery-white. Often has a prominent 40 30 No 5 3 N/A x Holly Oak umbrella form. Prune for form. Umbellularia californica Drought tolerant native in S. OR. Fruit looks like 60 30 No 5 1,2,3 Oregon Myrtlewood miniature limes.

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GSI Tree Lists Rev. 6-15-2015 Large Deciduous Columnar Trees Guidance Statement: Use columnar trees only in areas that have restricted space or near wires.

Mature Under Min Strip Planting Fall SDOT Scientific & Common Name Spread Design Comments Height Wires? Width Zone Color List Acer nigrum ‘Green Column’ Green Column Black Sugar Maple 50 10 No 6 3 Yes x

Ginko biloba ‘Princeton Sentry’ Princeton Sentry Ginkgo 40 15 No 6 3 Yes x Prune for form

Quercus robur ‘fastigiata’ 40 15 No 6 3 N/A x Skyrocket Oak

Large Deciduous Trees Guidance Statement: Broad canopy trees provide greater stormwater function and increased shade. Scientific & Common Name Mature Under Min Strip Planting Fall SDOT Spread Design Comments Height Wires? Width Zone Color List Acer saccharum 'Commemoration' or 'Bonnfire' No Yes Commemoration or Bonfire Sugar Maple 50 35 6 1,2,3 x Resistant to leaf tatter. Fagus sylvatica 50 40 No 6 3 Yes x Silvery-grey bark. Can't handle root disturbance. Green Beech Fagus sylvatica 'Asplenifolia' 60 50 No 6 3 Yes x Can't handle root disturbance. Fernleaf Beech Ginkgo biloba 'Magyar' More upright and narrow than 'Autumn Gold’. Needs 50 25 No 6 3 Yes x Magyar Ginkgo training when young. Liriodendron tulipifera 60+ 30 No 8 1,2,3 Yes x Fast-growing tree. Tulip Tree Platanus x acerifolia 'Bloodgood' More anthracnose resistant than other varieties – large 50+ 40 No 8 1,2,3 N/A x Bloodgood London Planetree tree that needs space. Quercus bicolor No N/A Swamp White Oak 60 45 8 1,2,3 x Shaggy peeling bark. Wet-soil tolerant. Quercus coccinea 60 40 No 6 3 Yes x Good fall color Scarlet Oak Quercus imbricaria 60 50 No 6 3 N/A x Leaves can persist throughout the winter Shingle Oak Quercus rubra Fast growing oak – large tree that needs space. Heavy 60 45 No 8 1,2,3 Yes x Red Oak acorn producer. Tilia tomentosa, Silver Linden 60 50 No 6 3 Yes Larger leaves than Littleleaf Linden. Fragrant flowers. Ulmus ‘Frontier’ or 'Morton Glossy' No Yes Frontier or Triumph Elm 50 35 6 1,2,3 x Resistant to Dutch elm disease Zelkova serrata ‘Greenvase’ or 'Village Green' Exfoliating bark. Dark green leaves turn orange-red and 45 40 No 6 3 Yes x Green Vase or Village Green Zelkova purple in Fall.

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GSI Tree Lists Rev. 6-15-2015 Medium / Large Deciduous Trees Guidance Statement: Broad canopy trees provide greater stormwater function and increased shade. Scientific & Common Name Mature Under Min Strip Planting Fall SDOT Spread Design Comments Height Wires? Width Zone Color List Acer campestre ‘Evelyn’ No Yes Queen Elizabeth Hedge Maple 40 30 5 1,2,3 x More upright branching than the species. Acer freemanii 'Autumn Blaze' Cross between red and silver maple – fast growing with Autumn Blaze Maple 50 40 No 6 1,2,3 Yes x good fall color

Acer rubrum ‘ Scarsen’ Leaves are darker green and larger than those of other Scarlet Sentinel Maple 40 25 No 6 1,2,3 Yes x Red Maples and hold up well in summer heat. Upright branch habit. Aesculus x carnea ‘Briottii’ Do not use near greenways or bicycle routes due to litter. Red Horsechestnut 30 35 No 6 3 N/A x Resists heat and drought better than other horsechestnuts Betula nigra River Birch 40 30 No 5 1,2,3 Yes Excellent flaky bark. Resistant to Bronze Birch Borer

Cercidiphyllum japonicum 45 40 No 8 1,2,3 Yes Katsura tree Eucommia ulmoides Dark green, very shiny leaves – insignificant fall color 50 40 No 6 3 N/A x Hardy Rubber Tree Fagus sylvatica 'Rohanii' Purple leaves with wavy margins. 50 30 No 6 3 N/A x Purple Oak Leaf Beech Ginko biloba ‘Autumn Gold’ 45 35 No 6 3 Yes x Narrow when young. Autumn Gold Ginkgo Nothofagus antarctica 50 35 No 5 3 No x Rugged twisted branching and petite foliage. Antarctic Beech Quercus frainetto 50 30 No 6 3 N/A X Drought resistant – green, glossy leaves in summer. Italian Oak Sophora japonica 'Regent' Has a rapid growth rate and tolerates city conditions, 45 40 No 6 3 Yes x Japanese Pagodatree heat, and drought. Tilia cordata ‘Greenspire’ Greenspire Linden 40 30 No 6 3 Yes x Symmetrical, pyramidal form. Fragrant flowers.

Ulmus parvifolia ‘Emer II’ Exfoliating bark and good fall color – Resistant to Dutch 45 35 No 5 1,2,3 Yes x Allee Elm Elm Disease

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GSI Tree Lists Rev. 6-15-2015 Medium Columnar DeciduousTrees Guidance Statement: Use columnar trees only in areas that have very restricted space or near wires. Scientific & Common Name Mature Under Min Strip Planting Fall SDOT Spread Design Comments Height Wires? Width Zone Color List Acer rubrum ‘Bowhall’ Bowhall Maple 40 20 No 6 1,2,3 Yes x Upright, pyramidal form

Carpinus betulus ‘Fastigiata’ Pyramidal European Hornbeam 40 15 No 5 1,2,3 Yes x Broadens when older.

Fagus sylvatica ‘Dawyck Purple’ Dawyck Purple Beech 40 12 No 6 3 Yes x Purple foliage.

Oxydendron arboreum 35 12 No 5 3 Yes x Consistent and brilliant fall color. Sourwood Nyssa sylvatica 40 20 No 6 1,2,3 Yes X Chunky bark. Takes standing water and drought. Tupelo

Medium Deciduous Trees Guidance Statement: Use medium deciduous trees where large trees cannot fit or to increase species variety. Mature Under Min Strip Planting Fall SDOT Scientific & Common Name Spread Design Comments Height Wires? Width Zone Color List Acer rubrum ‘Karpick’ Finer texture than other narrow forms of columnar Karpick Maple 40 20 No 6 1,2,3 Yes x maple.

Acer truncatum x A. platanoides ‘Keithsform' or Reliable reddish orange fall color. 'Warrenred' 35 25 No 5 3 Yes x Norwegian or Pacific Sunset Maple Cladrastis kentukea White flowers in spring, resembling wisteria flower – Yellowwood 40 40 No 5 3 Yes x blooms profusely only every 2 to 4 years – yellow/gold fall color Cornus controversa 'June Snow' Frothy, 6-inch clusters of white flowers in June 40 30 No 5 3 Yes x Giant Dogwood Corylus colurna Tight, formal, dense crown - Nice central leader. Not for Turkish Filbert mixed use areas with high pedestrian traffic dues to 40 25 No 5 3 Yes x significant debris from nuts. Drought tolerant. Plant smaller sizes in order to facilitate establishment. Magnolia denudata 6” inch fragrant white flowers in spring. 40 40 No 5 3 N/A x Yulan Magnolia Ostrya virginiana Hop like fruit – slow growing 40 25 No 5 3 Yes x Ironwood Pterostyrax hispida Pendulous creamy white flowers – fragrant 40 30 No 5 3 Yes x Fragrant Epaulette Tree Ulmus parvifolia 'Emer I' High resistance to Dutch Elm Disease. Drought Athena Classic Elm 30 35 No 5 1,2,3 Yes x resistant. Cinnamon colored exfoliating bark.

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GSI Tree Lists Rev. 6-15-2015 Small Conifer /Broad-Leaved Evergreen Trees Guidance Statement: Ornamental in appearance, provides year-round function. General O&M Statement: Prune up yearly for sight clearance. Mature Under Min Strip Planting Fall SDOT Scientific & Common Name Spread Design Comments Height Wires? Width Zone Color List Chamaecyparis obtusa gracilis 15 6 Yes 5 3 Drought tolerant when established. Slender Hinoki False Cypress Embothrium coccineum Brilliant orange red flowers in late spring. Tree can 30 15 No 5 3 Chilean Flame Tree sucker. Eucryphia glutinosa 25 15 Yes 5 3 Semi-evergreen. Best in part shade. Brushbush Magnolia grandiflora 'Edith Bogue' 18 12 Yes 5 1,2,3 Excellent BLE magnolia due to hardiness. Edith Bogue Magnolia Magnolia grandiflora ‘Victoria’ 25 20 Yes 5 1,2,3 N/A x Victoria Evergreen Magnolia Magnolia maudiae (=Michelia maudiae) 25 20 Yes 5 3 NCN Magnolia virginiana 35 35 5 1,2,3 x

Quercus hypoleucoides 30 15 No 5 3 Quercus myrsinifolia 30 15 No 5 3 Chinese Evergreen Oak

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GSI Tree Lists Rev. 6-15-2015 Small Deciduous Trees Guidance Statement: Use small trees only in areas that have restricted space, under wires or possibly if room as a large accent shrub. Try to select a species that would add variety to the streetscape. Scientific & Common Name Mature Under Min Strip Planting Fall SDOT Spread Design Comments Height Wires? Width Zone Color List Acer buegerianum Trident Maple 30 30 Yes 5 3 Yes x Must train to a single stem – interesting bark.

Acer circinatum Vine Maple 25 25 Yes 5 3 Yes x Avoid using on harsh sites - native tree.

Acer griseum 30 20 Yes 5 3 Yes x Peeling cinnamon colored bark. Paperbark Maple Acer tartaricum 20 20 Yes 5 3 Yes Tartarian Maple Acer triflorum Multi seasonal interest with tan, exfoliating bark and red, 25 20 Yes 5 3 Yes x Three-Flower Maple orange/red fall color. Amelanchier laevis 'Snowcloud' 25 15 Yes 4 3 Yes Snowcloud Serviceberry Asimina triloba Yes N/A Paw Paw 30 20 5 1,2,3 x Burgundy flower in spring before leaves. Betula nigra 'Little King' 10 12 Yes 5 1,2,3 Yes Suitable for enclosed vertical walls Little King River Birch Carpinus caroliniana 25 20 Yes 5 1,2,3 Yes x Good fall color (variable – yellow, orange, red) American Hornbeam Cornus kousa x nuttallii 'Starlight' 20 20 Yes 4 3 Yes Starlight Dogwood Lagerstroemia 'tuscarora' Light cinnamon brown bark lends year round interest – Tuscarora Hybrid Crape Myrtle 20 20 Yes 4 3 Yes x drought resistant – likes a warm site

Maackia amurensis Exfoliating bark – flowering in June or July - varies in 30 20 Yes 5 3 N/A x Amur Maackia intensity from year to year Magnolia 'Elizabeth' 30 20 Yes 5 3 N/A x Yellowish to cream colored flower in spring. Elizabeth Magnolia Magnolia 'Galaxy' 25 25 Yes 5 1,2,3 Yes x Suitable for enclosed vertical walls. Showy pink flowers. Galaxy Magnolia Magnolia kobus ‘Wada's Memory’ Drought tolerant. Does not flower well when young. Yes Yes Wada's Memory Magnolia’ 30 20 5 3 x Malus 'Lancelot' ('Lanzam') 15 15 Yes 4 3 Yes x Red flower buds, blooming white – red persistent fruit Lancelot Crabapple Parrotia persica Blooms before it leafs out – drought tolerant - Varied fall 30 20 No 5 3 Yes Persian Parrotia color - reds, oranges and yellows. Rhamnus purshiana 30 20 Yes 5 1,2,3 Yes x Suitable for enclosed vertical walls Cascara Salix matsudana 'Tortuosa' 30 15 Yes 5 1,2,3 Yes Do not use with underdrain. Corkscrew willow Stewartia pseudocamellia Camellia-like flowers in summer. Interesting bark. Slow 25 15 Yes 5 3 Yes Japanese Stewartia grower. Styrax japonica Reliable and easy to grow, it has plentiful, green ½” inch 25 25 Yes 5 3 Yes x Japanese Snowbell seeds. Flowers similar to lily in the valley. Tilia cordata ‘Chancole’ or 'De Groot' Pyramidal when young. Fragrant flowers that attract Chancellor or De Groot Littleleaf Linden 30+ 20 No C=6, D=5 3 Yes x bees. One of the smaller stature littleleaf lindens.

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GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix H: Comparison of Watering Methods Analysis Example WTD Barton CSO Control Project

• King County Barton Memo #21 – Irrigation Approach and Comparison Analysis, June, 28, 2012*

*This example was for a design that consolidated the bioretention cells at the end of a block.

MEMORANDUM # 21 FOR INTERNAL DISCUSSION PURPOSES

DATE: June 28, 2012

TO: Mary Wohleb, PMP, King County WTD Chris Tiffany, King County WTD Harold Perry, King County WTD

FROM: Jennifer Lathrop, PLA Peg Staeheli, PLA

RE: Task #1320 – Irrigation Approach & Comparison Analysis KC WTD - BARTON CSO CONTROL PROJECT WITH GSI (E00222E11) SvR # 11021

MEMORANDUM PURPOSE This memorandum has been prepared for King County Wastewater Treatment Division (KCWTD)’s Barton Combined Sewer Overflow (CSO) control project with Green Stormwater Infrastructure (GSI) as part of TASK #1320.

The purpose of the memorandum is to provide King County Wastewater Treatment Division (KC WTD) with the basis of methodology and assumptions used in developing a matrix comparing irrigation/watering alternatives for new landscape areas for the GSI systems and provide a recommended approach for irrigating/watering the GSI systems. The matrix is based on the 30% conceptual design for Barton CSO Control project with GSI.

PROJECT BACKGROUND In 2008 KCWTD reported that the Barton CSO facility had four overflows per year on average that discharge a total of four million gallons into Puget Sound Civil Engineering near the Fauntleroy Ferry Terminal in West Seattle. A CSO event is when a Landscape Architecture mixture of raw sewage and stormwater discharges into local water bodies. In Environmental Restoration order to provide CSO control of no more than one overflow per year for Planning compliance with Department of Ecology requirements (Ecology), the project proposes to utilize Green Stormwater Infrastructure (GSI) to filter and infiltrate 1205 Second Avenue combined sewer conveyance system. The reduction in stormwater runoff Suite 200 volume will reduce the CSO overflow events. Seattle, WA 98101 The GSI approach includes installing bioretention swales along multiple streets Phone: 206.223.0326 within the Project Area in order to intercept, treat and reduce the amount of Fax: 206.223.0125 stormwater discharging into the combined sewer pipes. Once the stormwater [email protected] has filtered through the bioretention soil, it will discharge into an

underdrain that then conveys the flows to a structure (UIC well) for deep infiltration into a soil layer identified as Vashon Advance Outwash. The Project Area for implementing GSI for Barton’s CSO control is an area within Barton 416 Subbasin. The Project Area is from SW Othello Street to SW Barton Street and from an alley just west of 34th Avenue SW to approximately 30th Avenue SW.

COMPARISION OF FOUR ALTERNATIVES FOR WATERING Four alternative approaches for watering the GSI systems were used for this comparative analysis. They include:  Fixed spray sprinkler circuits  Low volume drip circuits  Quick-coupling valve systems  Manual watering via water trucks

For the comparative analysis we looked at the following areas:  Ease of implementation, including familiarity of proposed irrigation system components with construction personnel.  Expected maintenance and repair criteria.  Maintenance labor intensity.  Neighborhood impacts (post construction).  Operational needs.  Maintenance needs.  Water connections.  Power sources (assumes implementation of battery-operated controllers and/or battery-operated valves).  Watering frequency and efficiency.  Watering hours.  Expected life cycle.  Potential obstructions.  Establishment versus long-term considerations.

The comparison of the four approaches used the material, labor, equipment and watering costs developed for retrofitting four streets with GSI as templates (see SDOT Design Guidance Meeting materials dated 12/20/2011). These costs were extrapolated to a total of 31 retrofitted streets (shown in the 30% SIP drawings issued 4/6/2012) from 1st year implementation and maintenance, through plant establishment (currently planned as years 2 through 4), post plant establishment (years 5 through 10) and beyond through year 15. We selected 15 years as the cut off for this comparative analysis because of the expected lifespan of typical drip irrigation components. Escalation was not included in the costs and the estimate was based on Spring 2012 material, equipment, labor and SPU water rates.

FOR INTERNAL DISCUSSION PURPOSES

Memorandum #21 KC WTD – BARTON CSO CONTROL PROJECT WITH GSI Task #1320 – Irrigation Approach & Comparison Analysis June 28, 2012 Page 3 of 4

SUMMARY A summary of the results for each of the areas reviewed in the comparison analysis of the four systems is shown on the attached matrix. Some areas to highlight include the following:

Cost comparisons: The projected material, labor and water costs within the matrix yielded the following total per square foot costs for a 15-year period beginning at initial installation.  Fixed spray sprinkler circuits: $3.75 to $4.50  Low volume drip circuits: $4.25 to $5.50  Quick-coupling valve systems: $16.00 to $18.00  Watering truck: $19.00 to $22.25

Community Impacts: Implementation of the GSI retrofits may be perceived as disruptive to the existing Sunrise Heights and Westwood Community neighborhoods, including the chosen irrigation watering approach for new planting areas. The following summarizes potential impacts from four approaches to irrigation: Low impacts:  Operation of fixed spray irrigation circuits may introduce “white noise” from sprinkler spray nozzles.  Broken sprinkler heads could create localized puddles and runoff of water during operation.  Drip tubing can become exposed and accessible visually and physically.  Trees could be watered by gators bags minimizing labor and improving effectiveness.

Medium impacts:  Maintenance personnel would be present during daylight hours two to three times a week during establishment to conduct hand watering of plants.  Pulling of hoses along the ground plane can pose a tripping hazard.  Pulling of hoses could damage some plantings.

High impacts:  Parking and maneuvering of watering trucks during daylight hours could be disruptive to neighborhood vehicular and pedestrian circulation.  Maneuvering of water trucks may result in uneven irrigation.  Truck and water pump noise and exhaust levels need to be considered.

FOR INTERNAL DISCUSSION PURPOSES

Memorandum #21 KC WTD – BARTON CSO CONTROL PROJECT WITH GSI Task #1320 – Irrigation Approach & Comparison Analysis June 28, 2012 Page 4 of 4

NEXT STEPS While it appears that a fixed spray approach is most cost effective in the long run there are design and management issues that require additional consideration. Project sequencing, adjacency of GSI between blocks, length of GSI within the block, plant selection and establishment contract all factor into the best value decision. The approach will also need to be viewed in the context of activity in the neighborhood. There may be advantages to a watering truck or hybrid approach as that will put additional eyes on the system to review function and other maintenance issues. It is our recommendation that the project continue to carry to cost of a fixed spray system into Phase 2 with the understanding that it is a placeholder to be reviewed following 60%.

Next steps to be undertaken include:

1. Coordinate with agency and lead operations and maintenance personnel for watering recommendations within the context of the design variables. 2. Confirm agency internal, other agency or contract approach for routine maintenance. 3. Confirm estimated costs and lifecycle. 4. Review life cycle expectancy of specific irrigation components. 5. Consider and address potential neighborhood impacts.

If you have any questions or comments, please give us a call/email.

Attachment: Irrigation Approach & Comparison Analysis Matrix

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FOR INTERNAL DISCUSSION PURPOSES MATRIX: COMPARISON OF FOUR ALTERNATIVES FOR WATERING BARTON CSO CONTROL PROJECT WITH GSI (E00222E11) SvR Memo #21 – Task 1320, Irrigation Approach & Comparison Analysis June 28, 2012 SvR# 11021

Item Fixed Spray Sprinkler Circuits Low Volume Drip Circuits Quick-Coupling Valve System Watering Truck

Quick-coupling valves on irrigation mains provide a Drip tubing with built-in drip emitters on circuit Spray heads on circuit zones per planting type. remote water source to connect a hose for manual Includes water tanks and water pumps on the back zones per planting type. Circuits are activated by Circuits are activated by remote control valves on watering. Quick-coupling valves are activated by of a flat-bed or heavy-duty truck. Water is from a remote control valves on timers. Water is from a Description timers. Water is from a potable water source and is valve keys. Water is from a potable water source nearby hydrant or other separately metered potable potable water source and is separately metered. separately metered. Spray heads are set flush to and is separately metered. Quick-coupling valves source. Hoses connect to the tank/pump assembly Drip tubing set below mulch and is not visible during grade and “pop-up” during operation. are set slightly below grade and are enclosed within for manual watering. operation. valve access boxes set flush to grade.

Construction and maintenance personnel need to Maintenance personnel need to be familiar with be familiar with typical quick-coupling components, Construction and maintenance personnel need to Construction and maintenance personnel need to plant watering needs and function of soils within installation and operation. Maintenance personnel Implementation be familiar with typical right of way fixed spray be familiar with typical right of way drip system bioretention areas. Requires procurement or need to be familiar with plant watering needs and system components, installation and operation. components, installation and operation. securing of trucks, water tanks, pumps and hoses function of soils within bioretention areas. Requires (not included). procurement of hoses (not included).

Due to subsurface installation, drip tubing circuits Allows for easy visual observation of system and do not allow for easy visual observation of proper circuit operations and water coverage. Breaks in operation and water coverage. Damaged or Breaks in piping or malfunctioning quick-coupling Maintenance / piping, clogged nozzles, malfunctioning or damaged severed drip tubing and/or clogged drip emitters are valves can be easily identified, isolated and General routine maintenance of trucks, water tanks, Repair Criteria heads or valves can be easily identified, isolated typically only identified after plant materials exhibit repaired. General routine maintenance of hoses pumps, hoses and valves are needed. and repaired. Maturing shrub canopy growth could signs of significant stressed or are dying due to lack and valves are needed. possibly block spray patterns. of water. Shrub canopy growth won’t affect water coverage.

Minimally intensive at initial installation (trenching Somewhat intensive at initial installation only (due Intensive at initial installation only, then monthly for mains, sub-mains and quick-coupling valves at Very labor intensive, assumes minimum 3x per to reduced trenching afforded by drip tubing), then inspections of circuit operation during growing 50’ to 100’ spacings). Very labor intensive, week for 10 weeks through plant establishment and periodic inspections of circuits monthly during season. Affords significant reduction in labor hours assumes minimum 3x per week for 10 weeks post-plant establishment phases, then 2x per week Maintenance/ growing season. Affords significant reduction in when compared to hand-watering via quick- through plant establishment and post-plant for 10 weeks thereafter. Each site visit requires labor hours when compared to hand-watering via Labor Intensity coupling system or watering truck, though establishment phases, then 2x per week for 10 travel to site, travel to water source location, water quick-coupling system or watering truck, though personnel need to be familiar with irrigation weeks thereafter. Each site visit requires travel to tank fill-up, and hand watering of plants. Assume 2 personnel need to be familiar with irrigation components. site, set-up of hoses and hand watering of plants. laborers each watering occurrence. components. Assume 2 laborers each watering occurrence.

High: Parking and maneuvering of watering trucks Moderate: Maintenance personnel would be during daylight hours would be disruptive to Neighbor Low: Circuits would be operational from midnight to None. Circuits could be operational any time of day, present during daylight hours to conduct hand neighborhood vehicular and pedestrian circulation. Impacts (Post 6:00am. System activation results in gentle “white but late evening/early morning hours are preferred. watering of plants. Hoses can pose a tripping Truck and water pump noise and exhaust levels noise” from sprinkler spray nozzles. System activation results in no noticeable noise. Construction) hazard. need to be considered. Hoses can pose a tripping hazard.

Fuel for water truck and water pumps. General Periodic status reports. Coordination with agency Periodic status reports. Coordination with agency General routine maintenance of maintenance Operational routine maintenance of trucks, water tanks, pumps, staff. Annual battery replacements for controllers staff. Annual battery replacements for controllers vehicles, hoses and valves are needed. Periodic hoses and valves are needed. Periodic status Needs and/or control valves. and/or control valves. status reports. Coordination with agency staff. reports. Coordination with agency staff.

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Item Fixed Spray Sprinkler Circuits Low Volume Drip Circuits Quick-Coupling Valve System Watering Truck

Drip tubing is susceptible to damage and vandalism if mulch is displaced and tubing exposed (such as in areas of concentrated pedestrian crossings). Pop-up spray heads can be susceptible to Once exposed, large amounts of drip tubing could Maintenance General routine maintenance of hoses and valves General routine maintenance of trucks, water tanks, vandalism. Possible breakage of pipes could occur be easily pulled out of the ground by vandals. are needed. pumps, hoses and valves are needed. Needs with excavations exceeding 10” depth. Possible severing of drip tubing could occur with shallow excavation work. Possible breakage of pipes could occur with excavations exceeding 10” depth.

Options are for rainwater harvesting or traditional Options are for rainwater harvesting or traditional Options are for rainwater harvesting or traditional Options are for rainwater harvesting or traditional potable water. potable water. potable water. potable water. 1. Rainwater harvesting would require multiple 1. Rainwater harvesting would require multiple 1. Rainwater harvesting would require multiple 1. Rainwater harvesting would require multiple vaults and likely supplemental water would vaults and likely supplemental water would vaults and likely supplemental water would vaults and likely supplemental water would be needed during peak summer months. be needed during peak summer months. be needed during peak summer months. be needed during peak summer months. Water Source 2. Traditional potable water requires 2. Traditional potable water requires 2. Traditional potable water requires 2. Traditional potable water requires connections to public water mains and connections to public water mains and connections to public water mains and connections to public water mains and installation of water meters and backflow installation of water meters and backflow installation of water meters and backflow installation of water meters and backflow preventions at each water source preventions at each water source preventions at each water source preventions at each water source connection. connection. connection. connection.

System design will specify battery-operated System design will specify battery-operated controllers and/or circuit valves (assumed for costs controllers and/or circuit valves (assumed for costs below), eliminating the need for power connections, below), eliminating the need for power connections, Power Sources N/A N/A electrical meter and above-grade cabinets. electrical meter and above-grade cabinets. Conversion to solar powered controllers will be Conversion to solar powered controllers will be further explored in the next phase of design. further explored in the next phase of design.

Requires multiple watering cycles for each watering Requires multiple watering cycles for each watering event to provide deep root watering and to reduce event to provide deep root watering and to reduce System can provide multiple start-soak times for System can provide multiple start-soak times for runoff. (Note: Bioretention soils with underdrain will Watering runoff. (Note: Bioretention soils with underdrain will optimum water application without wasted runoff. optimum water application without wasted runoff. drain readily and don’t “hold” water as typical Frequency & drain readily and don’t “hold” water as typical Typical fixed spray systems are approx 65-70% Typical drip systems are approx 90-92% efficient in landscape soils.) Each site visit requires travel to landscape soils.) Each site visit requires travel to Efficiency efficient in terms of water use. terms of water use. site, travel to water source location, water tank fill- site, and hand watering of plants. Estimate below up, and hand watering of plants. Estimate below assumes 2 laborers each watering occurrence. assumes 2 laborers each watering occurrence.

During daylight hours and in accordance with City During daylight hours and in accordance with City Ideally midnight to 6:00am, but can be operational Watering Hours Midnight to 6:00am of Seattle SMC 25.08 noise ordinance for of Seattle SMC 25.08 noise ordinance for any time of day residential zones. residential zones.

Components are durable and long lasting (30+ Requires routine maintenance of trucks, water Components are durable and long lasting (20+ Components are durable and long lasting (15+ years) with standard maintenance, repairs and tanks, pumps, and hoses. Trucks and pumps, Life Cycle years) with standard maintenance, repairs and years) with standard maintenance, repairs and care. Requires routine maintenance of quick- depending on routine maintenance, may need care. care. coupling valves and hoses. replacement.

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Item Fixed Spray Sprinkler Circuits Low Volume Drip Circuits Quick-Coupling Valve System Watering Truck

Broadcast spray from hoses could overthrow water All components are installed flush with or below Piping and valve components are installed flush onto adjacent vehicles, walkways and private Potential All components are installed flush with or below finish grade. Drip tubing can become exposed if with or below finish grade. Hoses, pulled along the properties. Hoses, pulled along the ground plane finish grade. mulch covering is displaced. Exposed drip tubing ground plane during watering cycles can pose a Obstructions during watering cycles can pose a tripping hazard could pose a tripping hazard to pedestrians. tripping hazard to pedestrians. to pedestrians.

Establishment System reactivation after 3 to 5 years of non-use System reactivation after 3 to 5 years of non-use is System reactivation after 3 to 5 years of non-use is Crews can be dispatched at most any time versus Long- could be significant, depending on exposure of drip easily achievable with minimal costs. Crews can be easily achievable with minimal costs. depending on need. Term tubing and damage to drip irrigation components. dispatched at most any time depending on need.

Estimated Labor and Water Costs

Item Fixed Spray Sprinkler Circuits Low Volume Drip Circuits Quick-Coupling Valve System Watering Truck

Installation & Labor Costs – $1.45 to $1.75 per square foot $0.95 to $1.25 per square foot $2.04 to $2.33 per square foot $1.60 to $1.80 per square foot 1st year

Labor Costs – Plant $0.07 to $0.09 per square foot $0.10 to $0.13 per square foot $1.22 to $1.38 per square foot $1.44 to $1.62 per square foot Establishment (2 to 4 yrs)

Labor Costs – Post Plant $0.12 to $0.14 per square foot $0.19 to $0.25 per square foot $1.02 to $1.15 per square foot $1.20 to $1.35 per square foot Establishment (5 to 10 yrs)

Labor Costs – 11-15 yrs $0.15 to $0.18 per square foot $0.29 to $0.38 per square foot $1.02 to $1.15 per square foot $1.20 to $1.35 per square foot

Water Cost – each year (based on SPU 2012 water $0.04 per square foot $0.027 per square foot $0.05 per square foot $0.05 per square foot rates)

Total Accumulative Costs $3.75 to $4.50 per square foot $4.25 to $5.50 per square foot $16.00 to $18.00 per square foot $20.00 to $22.25 per square foot After 15 years

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GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix I: Draft King County Integrated Pest Management Document

GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix J: GSI Maintenance Resources and Reference List

GSI Manual, Volume V – Operations & Maintenance Appendix

APPENDIX G

GSI MAINTENANCE REFERENCE LIST 1.01 SUMMARY A. This Appendix provides a list of recommended publications, resources and references for use by maintenance personnel to ensure that the system will function as intended for CSO control. B. In addition to reviewing materials that were prepared from SPU/WTD’s other GSI Manual Volumes, the following are resources specific for the Operations, Maintenance and Inspection of GSI: • Ecology’s Guidance Document: Western Washington Low Impact Development (LID) Operations and Maintenance (O&M) (current publication) • City of Seattle Stormwater Manual (Current Edition) • Traffic Control Manual For In-Street Work (City of Seattle, current edition)

1.02 AGENCY BACKGROUND RESOURCES • SPU/WTD GSI Manual Volumes I through VI • SDOT’s Street and Sidewalk Pavement Opening and Restoration (Current Edition) • Seattle Public Utilities’ Communications and Public Engagement Guidelines, Sewer and Stormwater Pollution Prevention, Updated 5/10/2012 • WTD’s Community Engagement Guide • Ecology Guidance for UIC Well Registration • Ecology's Guidance for UIC Wells that Manage Stormwater (current publication) • Other regulatory compliance or legal documents, such as a copy of the agency's Consent Decree

GSI Manual, Volume V – Operations & Maintenance Appendix

1.03 RECOMMENDED GENERAL PUBLICATIONS, RESOURCES AND REFERENCES A. General Gardening 1. King County - Going Native brochure Planting techniques and suggested native plants and and layouts http://your.kingcounty.gov/dnrp/library/2003/gonative.pdf 2. Seattle Tilth: A non-profit organic gardening and urban ecology organization. Their website provides links to information on organic gardening, soils, plant selection and many other topics. Their Maritime Northwest Guide may be purchased from their website. http://www.seattletilth.org/ 3. Seattle Public Utilities: This agency provides information on natural systems drainage, lawn care, plant selections, water use and other topics. http://www.seattle.gov/util/EnvironmentConservation/MyLawnGarden/index.htm 4. Sunset Western Garden Book, 2001 Edition by Kathleen Norris Brenzel, 2001 5. WSU Extension - Gardening Fact Sheets http://county.wsu.edu/king/gardening/mg/factsheets/Pages/default.aspx 6. WSU Extension - Planting Landscape Plants Fact Sheet http://county.wsu.edu/king/gardening/mg/factsheets/Fact%20Sheets/Planting%20Techniqu es%20for%20Landscape%20Plants.pdf 7. WSU Snohomish County Extension An organization that provides year-round advice on landscape issues, such as pests, diseases and plant selection. They are available weekdays by phone at (425) 338-2400. http://snohomish.wsu.edu/ B. Plant Selection and Identification 1. A Field Guide to the Common Wetland Plants of Western Washington & Northwestern Oregon by Sarah S. Cooke, 1997 2. Plants Of The Pacific Northwest Coast: Washington, Oregon, British Columbia & Alaska by Pojar and MacKinnon, 2004 3. Right Plant, Right Place by Nicola Ferguson, 1984 C. Plant Maintenance 1. Tri-County Integrated Pest and Vegetation Management Guidelines http://www.lhwmp.org/home/ChemToxPesticides/documents/IPMTriCountyGuidelines.pdf 2. Cass Turnbull’s Guide to Pruning: What, When, Where, and How to Prune for a More Beautiful Garden by Cass Turnbull, 2004 3. Pruning Made Easy : A gardener’s visual guide to when and how to prune everything, from flowers to trees by Lewis Hill, 1998 4. Pruning and Training: A fully illustrated plant-by-plant manual by Christopher Brickell and David Joyce, 1996 5. The Compost Tea Brewing Manual by Dr. Elaine Ingham, 2005 (5th ed.) D. Disease and Pest Control 1. American Horticultural Society Pests and Diseases: The Complete Guide to Preventing, Identifying and Treating Plant Problems by Pippa Greenwood and Andrew Halstead, 2000 2. Journal of Pesticide Reform – Nonchemical Methods for Removing Unwanted Blackberry Plants http://www.pesticide.org/solutions/home-and-garden-toolbox/weed- solutions/blackberries 3. King County Department of Natural Resources This agency provides information on a variety of natural lawn and garden care topics. Detailed information on pest and weed- identification and control are available. http://www.kingcounty.gov/environment/stewardship/nw-yard-and-garden.aspx 4. King County - Noxious Weed Control Brochures http://www.kingcounty.gov/environment/animalsAndPlants/noxious-weeds/brochures- reports.aspx

GSI Manual, Volume V – Operations & Maintenance Appendix 5. The Organic Gardener’s Handbook of Natural Insect and Disease Control: A Complete Problem-Solving Guide to Keeping Your Garden and Yard Healthy Without Chemicals by Barbara W. Ellis, 1992 6. TNC Weed Management - Documents for Reed Canary Grass, English Ivy and Himalayan Blackberry http://www.invasive.org/gist/moredocs/phaaru01.pdf http://www.invasive.org/gist/moredocs/hedhel02.pdf http://www.invasive.org/gist/moredocs/rubarm01.pdf 7. Washington Department of Ecology - Mosquito Control http://www.ecy.wa.gov/pubs/0310023.pdf 8. WSU Extension - Insecticidal Soaps Info Sheet http://spokane- county.wsu.edu/spokane/eastside/Fact%20Sheets/C183%20Insecticidal%20Soaps%2005. pdf E. Irrigation 1. Rain Bird Winterization Guide www.rainbird.com/documents/diy/WinterizationGuide.pdf F. Additional resources and references 1. King County Stormwater Services http://www.kingcounty.gov/environment/waterandland/stormwater/problem-investigation- line. 2. Department of Ecology Stormwater Management Manual for Western Washington, 2012 Edition, Volume V. 3. Department of Ecology Guidance Document Western Washington Low Impact Development (LID) Operations and Maintenance (O&M), Current addition. 4. Low Impact Development Technical Guidance Manual for Puget Sound, December 2012, Washington State University Extension and Puget Sound Partnership. 5. Washington State Department of Ecology 2006 Guidance for UIC Wells that Manage Stormwater. 6. Washington Administrative Code 173-160, Minimum Standards for Construction and Maintenance of Wells. 7. City of Seattle Standard Specifications for Road, Bridge and Municipal Construction, 2011 Edition. 8. City of Seattle Standard Plans, 2011 Edition; 9. Seattle Department of Transportation Director’s Rule 5-2009 for Street and Sidewalk Pavement Opening and Restoration (current edition)

GSI Manual, Volume V – Operations & Maintenance Appendix

Appendix K: Roadside Bioretention Cell Care Guide

Roadside Bioretention Cell Care Guide

Rain gardens and bioretention cells capture stormwater runoff and let water soak into the ground as plants and soil filter pollutants.

These practices convert stormwater from a problem to a resource that replenishes groundwater and protects local waterways.

Built along the street, they also create attractive streetscapes and urban green spaces, provide natural habitat, and enhance pedestrian and bicycle safety.

Bioretention cells are more engineered than rain gardens, and have primary operations and maintenance (O&M) responsibility by the local government agency. This guide is for adjacent property owners or groups who are interested in supplementing that O&M. Roadside Bioretention Cell Care Program

Thank you for your interest in bioretention cell stewardship. This guide describes the activities of your local agency and what you can do to support those activities if you are interested.

Maintenance Responsibilities

Seattle Public Utilities and King County Wastewater Treatment Division routinely monitor all roadside bioretention cells to determine the level of work needed to maintain healthy plants and ensure the facilities function properly. Identifying problems early and addressing them will insure a long healthy life for the system. Please notify us if you see concerns.

Why Bioretention Cells Matter

Bioretention cells are an innovative and effective way to restore the health of Seattle’s urban watersheds. Over the last 150 years, we’ve covered our watersheds with streets, roofs, driveways and parking lots. In the process, we’ve increased stormwater runoff that causes pollution to flow into our creeks, lakes, the Duwamish River, and Elliott Bay. Bioretention cells help to protect and restore the Puget Sound and our local waterways.

Anatomy of a Bioretention Cell

1 Capture and Treatment Area Special soils that allow the water 3 to soak in.

2 Overflow Drain 1 Not all bioretention cells have one. These allow stormwater from larger storm 2 events to flow out if the raingarden is full. 3 3 Curb Opening Also called an inlet or outlet where stormwater can enter and exit

2 Roadside Bioretention Cell Care Guide | 2015 Plant Establishment Phase (first three years)

Young plants have tender roots and can be susceptible to damage without regular care. During this phase, the city or site developer contracts with professionals to care for the roadside bioretention cell.

Professional crews will: You can help by: • Check for proper function • Removing trash and debris • Remove sediment • Clearing curb openings and top of

• Clear curb openings and top overflow drain of overflow drain • Watering during dry periods • Remove trash and debris • Pushing aside accumulated

• Remove weeds sediment • Water plants • Prune, replace or remove trees or plants if necessary

Important Safety Guidelines When Working Near A Street

• Do not stand in street when performing maintenance activities.

• Make yourself visible. Wear brightly colored clothing or a safety vest.

• Since bioretention cells are next to the street, take extra caution and be aware of passing bicycles and vehicles.

• Wear sturdy shoes and thick gloves to help protect you from broken glass, sharp objects, pollutants, and other obvious or concealed hazards.

• Take care of your bioretention cell during daylight hours and avoid peak traffic times.

• Do not allow children younger than 10 years of age to work with you; older children must be accompanied by an adult volunteer. Keep in mind that adult supervision is critical when working within the street environment.

• Do not leave your tools unattended. Keep them out of the street and off the sidewalk so they don’t pose a hazard.

We don’t want you to get hurt, so please be safe. 3 Roadside Bioretention Cell Care Guide | 2015 Long-term Care Phase (after plants are established)

Professional crews will: • Check for proper function • Remove sediment • Clear curb openings and top of overflow drain • Remove trash and debris • Remove weeds • Water plants if necessary • Prune, replace or remove trees or plants if necessary

You can help by: • Removing trash and debris • Clearing curb openings and top of overflow drain • Pushing aside accumulated sediment • Watering during dry periods • Removing weeds

The Bioretention Cell Care Chart at right ► summarizes simple volunteer bioretention cell activities you can perform (See pages 6-9 for care how-to tips).

Please DO NOT:

Prune or trim plants and trees Add or replace plants Use chemical herbicides, fertilizers, or insecticides Modify or alter the function or design Add or remove bioretention soil, compost, mulch, or fill Store tools, lumber or other items in the rain garden Remove dead or dying plants Remove sediment Enter the systems when soils are wet (to protect soils)

4 Roadside Bioretention Cell Care Guide | 2015 Bioretention Cell Care Chart

After notifying us* that you want to help care for your local roadside bioretention cell, use this chart to make sure you know what to do. See the how-to steps on the following pages.

Bioretention Cell Professional Crew Activity Volunteer Activity Care and Maitenance Varies, 0-3 Year Varies, 0-3 Year Activity Long-term Long-term Establishment Establishment Care Phase Care Phase Phase Phase Clear curb openings of leaves, trash, and YES YES YES YES debris. Push aside sediment. Remove trash YES YES YES YES Clear top of overflow drain (do not lift the YES YES YES YES grate) Water only during YES YES NO YES periods of drought Remove weeds YES YES YES NO (with training)* Prune trees and plants YES YES NO NO Remove or replace YES YES NO NO trees and plants Remove sediment YES YES NO NO Structural/ Repairs To report damage or other To report damage or other repair needs call the number repair needs call the number Please DO NOT: below. below.

*Get training and let us know you are helping at 700milliongallons.org For questions about vegetation, please contact the Garden hotline at 206-633-0224

Please notify us when: Contact Information

• Plants or trees are damaged or need trimming for safety • If your bioretention cell has had standing water for more than 72 hours after it

stopped raining • There is damage or vandalism to the facility • There is something besides rain that has spilled into the bioretention cell 5 Roadside Bioretention Cell Care Guide | 2015 Caring for Your Bioretention Cell

The most important part of bioretention cell care is to make sure the facility captures and filters stormwater. So check your bioretention cell regularly to ensure water flows into the facility. If you see these problems let us know, or follow these care steps below:

Clear Curb Openings Clear curb openings so water can flow into the bioretention cell. Rake and remove leaves, trash and debris. Push aside, but do not remove, sediment to create a clear path for stormwater flow. The best time to clear curb openings is before a rain storm.

Clear Drains Make sure that overflow drains aren’t blocked. Remove leaves, debris and trash on top of grates. Do not lift grates. Do not attempt to clear if there is more than two inches of water ponded.

6 Roadside Bioretention Cell Care Guide | 2015 Remove Trash Pick up any trash you find and recycle, if appropriate, or throw into a trash can.

Watering Although bioretention cell plants can tolerate our dry summer climate, they can benefit from additional watering during extended dry periods or extreme heat. Please use a gentle, low-pressure spray setting to avoid erosion, and don’t water at a faster rate than the ground can soak it up.

7 Roadside Bioretention Cell Care Guide | 2015 Weed Removal – after the establishment phase

If unsure, don’t remove.

• Remove weeds only after the establishment phase, when desirable plants are mature.

• You can weed by hand or with a small hand trowel, weed fork, or garden hoe. In order to eliminate weeds, it is important to try and remove their root systems.

• Do not use chemical herbicides.

• After removing a weed, gently pat down the soil to prevent air pockets that expose the roots of established plants. Loose soils can also encourage new weeds.

• If you are unsure whether a plant is a weed or invasive species, please do not remove it - because it may be a plant we want. Maintenance crews will address it on their next routine visit.

• Please do not remove plants that appear dead. Crews will evaluate these and replace if necessary.

See pages 10 - 11 for a photo guide to help identify the most common invasive and unwanted weed species.

8 Roadside Bioretention Cell Care Guide | 2015 What is Debris?

• Grass clippings • Sticks • Leaves • Small branches • Sediment at curb cut

Remove debris by hand or with a rake. Gather debris and put it in a yard-waste bin or other appropriate disposal container.

The most important times to remove debris and trash from your bioretention cell is before and after a storm. Heavy rains can cause trash and debris to collect around curb openings and overflow drains and block stormwater flow.

Rake leaves from around your curb cut, especially in the fall when leaves can quickly clog inlets.

9 Roadside Bioretention Cell Care Guide | 2015 J Commonlyx Found Problem Weeds to Remove Desirable Plants (Do Not Remove) Problem Weeds to Remove The city uses native and specially selected plants that are adapted for Green Street conditions and that require minimal water and care. Native plants provide food and habitat for native birds and wildlife. The following are photos of com- monly found, desirable plants selected for Green Streets: Pigweed Amaranthus sp. Rubus armeniacus Himalayan Blackberry Slough Sedge Cornus kelseyii Carex obnupta Kelsey dogwood Dandelion Morning Glory Convolvulus arvensis Taraxacum officinale Taraxacum Douglas Iris Iris douglassii Oregon Grape Mahonia repens Clover Trifolium repens Trifolium Chenopodium album Common Lambsquarters Juncus patens Spreading rush Fragaria chiloensis Coastal Strawberry Vicia Sativa Vicia Traveler’s Joy Traveler’s Common Vetch Clematis vitalba

14 15 GREEN STREET CARE AND MAINTENANCE GUIDE I ENVIRONMENTAL SERVICES - CITY OF PORTLAND 2012 GREEN STREET CARE AND MAINTENANCE GUIDE I ENVIRONMENTAL SERVICES - CITY OF PORTLAND 2012 10 Roadside Bioretention Cell Care Guide | 2015 Problem Weeds to Remove Continued x Problem Weeds continued Sweet Clover Melilotus alba Canada Thistle Cirsium arvense Curly Dock Sow Thistle Rumex Crispus Sonchus arvensis Daucus carota Cardmine species Bittercress species Queen Anne’s Lace Queen Anne’s Chicory Herb Robert Chicorium intybus Geranium Robertianum

For more information and plant photos visit www.portlandonline.com/bes/GreenStreetStewards 11 Roadside Bioretention Cell Care Guide | 2015 WS 1297 rev 2012 Thanks to the Portland Bureu of Environmental Services for permission to base this guide on their earlier publication, City of Portland Green Street Stewards Guide.