TABLE OF CONTENTS. Page 2 of 14

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1 Pilot Trash Structural Treatment Control Study Implementation Plan March 2008

2 TABLE OF CONTENTS 1.0 INTRODUCTION BACKGROUND TRASH SOURCES AND PATHWAYS TO URBAN CREEKS ESTIMATED TRASH LOADING RATES City of Calabazas, CA City of Los Angeles, CA TRASH BEST MANAGEMENT PRACTICES (BMPS) PILOT STUDY OBJECTIVES AND DESIGN STUDY OBJECTIVES PARTICIPATING AGENCIES City of San Jose City of Sunnyvale SELECTION OF TRASH TREATMENT DEVICE STUDY AREA SELECTION AND CHARACTERIZATION DATA COLLECTION METHODS DATA ANALYSIS TECHNIQUES PILOT STUDY SCHEDULE REFERENCES...12 Page 2 of 14

3 SCVURPPP Pilot Trash Structural Treatment Control Study Implementation Plan 1.0 INTRODUCTION March 2008 Consumer items and waste materials including food and beverage containers (e.g., plastic bags and bottles), cigarette butts, food waste, construction and landscaping materials, furniture, electronics, tires and hazardous materials (e.g., paint, batteries) are discarded everyday in the Santa Clara Valley (California). While many of these items are properly disposed of, a portion are inappropriately discarded, 1) onto the urban landscape that drains into a stormwater conveyance systems (i.e., stormwater systems), or 2) directly into local creeks and channels. This portion is collectively called trash and once in local water bodies it can adversely impact Santa Clara Valley residents, visitors, fish and wildlife. Responding to water quality concerns regarding trash, the San Francisco Bay Regional Water Quality Control Board (Water Board) identified trash as a potential pollutant in urban creeks in 2001 and directed municipalities to assess the potential impairment of water quality produced by the presence of trash in creeks within their jurisdiction. The Water Board suggested that Bay Area municipalities define trash problems in water bodies, identify the sources of trash through monitoring or existing information, and develop a program of action to address the principle sources of trash. In response to the call to action from the Water Board, the Santa Clara Valley Urban Runoff Pollution Prevention Program (SCVURPPP or Program) began taking additional steps toward improving trash conditions in Santa Clara Valley urban water bodies. Specifically, the Program s Management Committee formed a Trash Ad Hoc Task Group and subsequently developed a multi-year Work Plan that outlined a strategy to address trash in urban creeks and channels in the Santa Clara Valley. Through Work Plan implementation, creek trash assessments were conducted by SCVURPPP Co-Permittees at approximately fifty sites between 2004 and The goal of the assessments was to better understand the level of trash and potential impacts at creek sites identified as problem areas. Results suggest that during the wet season, large amounts of trash are conveyed through stormwater from poorly kept commercial facilities, schools, bus stops and roads. During the dry season, wind blown trash from adjacent land uses and illegal dumping on creek banks appear to be the most important trash source-transport combinations. In addition, homeless encampments are sources of trash at some creek sites. Building on the completion of the Work Plan, Program staff developed a Draft Trash Management and Effectiveness Assessment Strategy (Strategy) in October The Strategy currently serves as a roadmap to guide future trash-related activities conducted by the Program. It includes three main tasks: 1. Identifying trash problem areas and sources; 2. Selecting and implementing appropriate control measures at high priority problem areas; and, 3. Assessing the effectiveness of control measure implementation. Recent, current and future activities conducted under the Work Plan and the Strategy are illustrated in Figure 1. The SCVURPPP Pilot Trash Structural Treatment Control Study (Trash Control Study) described in this implementation plan is designed to assist Co-permittees in completing Task 2.2 of the Strategy. Page 3 of 14

4 Task 1 Identifying Trash Problem Areas & Sources Task Define Trash Sources and Pathways Trash Problem Area Survey (2004) Rapid Trash Assessments (RTAs) and Keep America Beautiful (KAB) Surveys (On-going) Trash Sources and Pathways Conceptual Model (2007) Task Prioritize Trash Problem Areas by Watershed Rapid Trash Assessments (RTAs) and Keep America Beautiful (KAB) Surveys (On-going) Draft Prioritization of Trash Problem Areas in Santa Clara Basin Watersheds (2007) Task Re-prioritize Problem Areas as Necessary To be determined Task 2 Trash BMP Evaluation & Implementation Task Assess Known Effectiveness & Costs of Control Measures Trash BMP Tool Box (2007) Task 2.2 Implementation of Pilot Trash Control Measures Pilot Trash Treatment Control Measures Demonstration Project Implementation (2007) Pump Station Retrofit Evaluation (2008) Task Develop and Implement Long-Term Trash Management Strategies To be determined Task 3 Trash Control Measure Effectiveness Assessment Task Develop Effectiveness Assessment and Monitoring Strategy Trash Control Measure Effectiveness Assessment Plan (2008) Task 3.2 Implement Effectiveness Assessment Strategy To be determined Task 3.3 -Track & Report Findings & Recommendations To be determined Figure 1. Illustration of the SCVURPPP Pilot Trash Structural Treatment Control Study (Pilot Study) in the context of all major Trash Management and Assessment Strategy tasks. Page 4 of 14

5 2.0 BACKGROUND 2.1 Trash Sources and Pathways to Urban Creeks People are the fundamental source of all trash found in Santa Clara Basin urban creeks and San Francisco Bay. However, similar to other pollutants, more specific sources and associated transport processes must be identified to allow effective management actions to be implemented. Based on creek trash assessments and local agency staff knowledge of how trash is deposited and transported to local water bodies, there are four distinct source categories for trash to urban creeks: 1. Pedestrians who lack the willingness to properly dispose of waste or do not have access to waste containers are likely the greatest source of trash in local water bodies. Land areas where pedestrians litter typically include high foot traffic locations (e.g., shopping plazas, convenience stores, parks), transition points (e.g., bus stops, train stations, entrance to public buildings), and special event venues (e.g., concerts, sporting events and fairs). 2. Drivers and passengers who litter from Vehicles or do not adequately cover their vehicles when transporting trash and debris are also sources. Land areas that may generate trash from vehicles include roads, highways (on/off ramps, shoulders or median strips) and parking lots. 3. Waste Containers (e.g., trash receptacles, recycling bins and dumpsters) that are overflowing and/or uncovered, and improper handling of trash and recycling materials during curbside collection (e.g., residential and commercial areas). 4. Illegal Dumping of large volumes of trash within a watershed or directly into a waterway is a source typically in out of sight locations. This source includes trash illegally dumped or discarded by illegal encampments near or within riparian areas. Pedestrians, vehicles and inadequate waste container management are generally considered a chronic source of trash in urbanized areas and usually occur where there are high populations of people consuming products and generating waste. In contrast, illegal dumping typically occurs sporadically and in general consists of large items (e.g., furniture and tires) compared to other source categories. There are also four major trash transport pathways to urban creeks: A. Stormwater Conveyance Systems can transport trash to waterways from any combination of the four source categories described above during storm events and dry weather flows. Small and floatable trash items are particularly susceptible to transport through this pathway. B. Wind can also transport trash to creeks and stormwater conveyance systems, especially when sources are located adjacent to creeks with minimal riparian vegetation and obstructions (e.g., fences). C. Direct Disposal of trash into creeks or along creek banks also serves as a transport mechanism. Illegal dumping and pedestrian litter are the two most prevalent trash source categories applicable to this pathway. D. Downstream Transport of trash can occur once it enters a creek from any of the pathways described above. Depending on the physical characteristics of trash and the creek, trash may accumulate a creek sites or be transported to larger downstream water bodies (e.g., wetlands, bays and estuaries), where additional influence of tide, currents and wind can affect the distribution of trash. Page 5 of 14

6 Although the magnitude of trash in urban creeks from each source and transport pathway combination is currently unclear, SCVURPPP and Water Board creek trash assessments suggest that stormwater conveyance systems are an important transport pathway. Therefore, additional information is needed to better quantify the sources of trash entering the stormwater system and the magnitude of trash entering local creeks via this transport pathway. 2.2 Estimated Trash Loading Rates The composition of the trash, and rate at which it finds its way into the stormwater conveyance system, are highly variable. Contributing factors may include: Type and density of land uses (e.g., commercial, industrial and residential); Income level and environmental awareness of the community; and, Rainfall intensity and antecedent rainfall period. Several studies have attempted to quantify the amount of trash reaching the stormwater conveyance system from discreet land areas. However, most studies have been conducted in relatively small areas, or for relatively short periods of time, or both. The findings of a portion of these studies are discussed below City of Calabazas, CA The City of Calabasas owns and operates a Continuous Deflective Separation (CDS) unit that receives runoff from a land area of approximately 12.8 mi 2. The urbanized portion of this area is estimated to be about 0.10 mi 2. The volume of trash removed from the CDS unit in 1999 was 2,000 gallons of sludgy water and a 64-gallon bag about two-thirds full of plastic food wrappers. This volume represents approximately nine months of runoff. Based on these data, the Los Angeles Regional Water Quality Control Board (LA Water Board) estimates that the annual loading of trash from this 0.10 mi 2 urbanized area is approximately 64 gallons (640 gallons/ mi 2 ). These data were used as the current loading rate for the Trash Total Maximum Daily Load (TMDL) for the Los Angeles River Watershed (LA Water Board 2007) City of Los Angeles, CA The City of Los Angeles conducted an Enhanced Catch Basin Cleaning Pilot Project in compliance with a consent decree between the United States Environmental Protection Agency, the State of California, and the City of Los Angeles. The project goals were to determine debris loading rates, characterize the debris, and find an optimal cleaning schedule through enhanced catch basin cleaning. The project evaluated trash loading at two drainage basins: 1) Hollywood Basin (1,366 acres and 793 catch basins), mostly residential with some commercial and open space, and no industrial land; and, 2) Sawtelle Basin (2,267 acres and 502 catch basins) includes residential areas with some commercial, industrial and transportation-related uses, and some open space. The catch basins are inlet structures without a sump below the level of the outlet pipe to capture solids and trash washed down by stormwater. Catch basins were cleaned three to four times from March 1992 to December 1994 and yielded approximately 0.79 yd 3 (160 gallons) of debris per cleaning characterized as paper (26%), plastic wastes (10%), soil (33%), and yard trimmings (31%). The study also observed that the amount of plastic waste was less in residential areas and greater in non-residential areas, that paper waste was greater in commercial areas, and that soil and yard waste was greater in residential areas and open spaces. In another study by the City of Los Angeles, the amounts of trash generated based on land use were addressed in a report required by the MS4 permit and submitted by Public Works to the LA Water Board on May 3, The report described the accumulation and cleanout of man-made trash, sediment, and natural vegetation in 500 catch basin inserts and five hydrodynamic separators in the Ballona Creek and Los Angeles River watersheds between November 11, 2002 Page 6 of 14

7 and March 20, This period included 15 storm and one dry weather cleanouts. Land use types with highest litter generation per acre were commercial and industrial. 2.3 Trash Best Management Practices (BMPs) In 2006, SCVURPPP Co-permittees expressed an interest in better understanding the known effectiveness, costs, challenges and applicability of various Best Management Practices (BMPs) designed to reduce trash in municipal stormwater conveyance systems and water bodies receiving urban runoff. In response, the Program staff conducted an extensive literature review on trash BMPs and created the Trash BMP Tool Box (Tool Box). The Tool Box examines both institutional (non-treatment) BMPs and stormwater treatment BMPs. Examples of institutional BMPs include, street sweeping, public education campaigns and creek cleanup events. Treatment controls are physical devices that are installed at stormwater catch basins, within the stormwater conveyance system, at an outfall to a creek, or within a water body. Treatment BMPs for trash typically block, separate or catch items transported through this pathway. Common types include catch basin inserts, hydrodynamic separators and outfall netting devices. Historically, SCVURPPP Co-permittees have attempted to manage trash in watersheds and creeks using a variety of institutional BMPs. Although the effectiveness of institutional BMPs is difficult to assess, some attempts have been made to determine the success of trash removal via street sweeping and receptacle management. In addition, Co-permittees know the costs of their storm drain maintenance and street sweeping programs, and operation and maintenance requirements. Treatment controls for trash have been implemented by Co-permittees to a lesser extent than institutional controls. Therefore, it is not unreasonable to assume that Co-permittee staff has less understanding of capital and maintenance costs, maintenance requirements and proper application of treatment controls. In addition, many of the treatment controls reviewed in the Tool Box are relatively new and little is known about effectiveness and maintenance requirements/costs Full Capture Certification for Treatment BMPs Many types of stormwater treatment BMPs have been recently piloted Southern California as part of the Total Maximum Daily Load (TMDL) for trash within the Los Angeles River watershed. Based on design and effectiveness considerations, the LA Water Board can designate a trash treatment control as full-capture (~100% removal). By definition, full capture treatment devices must: Trap all particles retained by a 5-mm screen, and have a demonstrated treatment capacity that exceeds the peak flow rate resulting from a one-year, one-hour storm in the subdrainage area (LARWQCB 2007). As of October 2007, six full-capture designations have been approved by the LA Water Board. Treatment devices certified as full capture are listed below and examples are presented in Figure Catch basin inserts developed by the City of Glendale, a combination of brush and aluminum mesh; 2. Vertical trash capture screen inserts developed by Advanced Solutions, installed within catch basins; 3. Horizontal trash capture screen inserts developed by Advanced Solutions, installed within catch basins; 4. End-of-pipe trash nets developed by Fresh Creek Technologies, Inc; Page 7 of 14

8 5. Linear radial gross solids removal device configuration 1 (LR1 I-10) developed by Caltrans; and, 6. Inclined screen gross solids removal device configuration 1 (IS1 SR-170) developed by Caltrans. Fresh Creek Technologies End-of-Pipe Netting Advanced Solutions Vertical Screen Inserts CalTrans Linear radial gross solids removal device configuration Figure 2. Examples of treatment devices certified by the Los Angeles Regional Water Quality Control Board as a full capture for trash. 3.0 PILOT STUDY OBJECTIVES AND DESIGN 3.1 Study Objectives Based on (a) the continued focus and challenges associated with reducing trash discharged to Santa Clara Basin creeks and channels through the stormwater conveyance system; (b) the need to better understand the costs, effectiveness, and maintenance requirements related to stormwater treatment BMPs; and, (c) the need to better define major land-based sources of trash and associated land use characteristics, the SCVURPPP Co-permittees have launched a Pilot Trash Structural Treatment Control Study (Pilot Study). The Pilot Study is designed to answer the following management questions: 1. What are the trash loading rates from specific land uses to the stormwater conveyance systems? 2. What is percentage of different types of materials (e.g., trash, sediment, leaves, grass) removed by selected treatment devices? Page 8 of 14

9 3. What is the maintenance frequency needed for proper operation of selected BMPs? 4. What are the overall costs of treatment per amount (volume or weight) of trash removed? Specific objectives of the Pilot Study are to: 1. Increase the removal of trash (and to a lesser degree sediment associated pollutants) in stormwater conveyance systems via the implementation of treatment BMPs; 2. Estimate trash loading rates to stormwater conveyance systems in the Santa Clara Basin for various sources and/or land use types; 3. Characterize the types of trash removed by selected treatment BMPs; 4. Determine operation and maintenance requirements and associated costs for treatment BMPs implemented by SCVURPPP Co-permitees; and, 5. Identify opportunities and challenges for future implementation. In addition, through the implementation of this Pilot Study, Co-permittees will gain valuable information that will assist them in addressing trash control requirements through the Municipal Regional Permit (MRP), which is currently being developed by the SF Bay Water Board. 3.2 Participating Agencies The two largest cities in Santa Clara County, the City of San Jose and the City of Sunnyvale, agreed to participate in the Pilot Study. Information collected through their participation will allow other SCVURPPP Co-pemittees to gain insight into the most dominant trash sources and the most effect ways to reduce trash from entering urban creeks through stormwater conveyance systems City of San Jose With roughly 950,000 residents, the City of San Jose is the third-largest city in California, and the largest in Santa Clara County. The City is roughly 178 mi 2 in size, has over 30,000 stormwater inlets that receive drainage from land uses presented in Table 1. These inlets convey stormwater to approximately 760 outfalls, which discharge to local creeks City of Sunnyvale The City of Sunnyvale is the second largest city in Santa Clara County with approximately 133,000 residents. Sunnyvale is roughly 23 mi 2 in size, and has roughly 4,183 municipal stormwater inlets, 25 outfalls to local creeks, and 48 outfalls to two storm drainage channels that connect to South San Francisco Bay. Table 1. Size (mi 2 ) and percentages of land use types in the cities of San Jose and Sunnyvale (Santa Clara Valley Urban Runoff Management Plan ). Land Use Type San Jose Sunnyvale Commercial 7.1 (4%) 1.75 (7%) Light and Heavy Industrial 16.2 (9%) 4.5 (18%) Public/Institutional/Schools 8.9 (5%) 2.25 (9%) Parks/Open Space 8.9 (5%) 1.25 (5%) Agriculture/Vacant 7.1 (4%) 1.0 (4%) Roads 28.5 (16%) 0.5 (2%) Single Family Residential 7.25 (29%) (59%) Multi-Family Residential 3.75 (15%) Total Page 9 of 14

10 3.3 Selection of Trash Treatment Device Pilot Trash Control Study Implementation Plan To determine the type(s) of treatment devices that could be implemented during the Pilot Study to meet the objectives of the Pilot Study, the Program reviewed existing information presented in the Trash Tool Box. The following criteria were used to select the device(s) appropriate for the Pilot Study: 1. Must be certified as full-capture by the LA Water Board to have confidence in the data for developing trash loading rates; 2. Should be relatively easy to install and remove if flooding becomes an issue; 3. Should have been successfully installed and maintained by municipalities in Southern California and applicable to the types of drainage infrastructure in the cities; and 4. Should be relatively easy to maintain by Public Works crews at minimal costs. Based on these criteria and extensive field reconnaissance, the City of San Jose and the City of Sunnyvale selected a catch basin insert device designed and produced by Advanced Solutions as the primary trash treatment BMP that will be used during the Pilot Study. The StormTek catch basin insert is designated as a full capture treatment device and consists of a perforated metal screen placed horizontally or vertically in front of the storm drain pipe outlet within a catch basin (Figure 3). The StormTek device is capable of catching smaller and larger debris and uses the volume of the catch basin to retain trash before it is conveyed through the stormwater conveyance system. The debris captured remains until it is removed by a maintenance crew. In addition, the StormTek device is scalable to fit many catch basin sizes and dimensions. This makes them uniquely appropriate in cities with older stormwater infrastructure like the Cities of San Jose and Sunnyvale. Figure 3. Example of the StormTek catch basin inserts which was selected for the SCVURPPP Pilot Study. 3.4 Study Area Selection and Characterization Approximately 80 StormTek devices will be installed in the Cities of San Jose and Sunnyvale. The devices will be located to help meet two objectives of the Pilot Study. First, the participating cities are interested in maximizing the volume of trash removed through the Pilot Study (i.e., Objective #1). Therefore, the most direct way to achieve this objective is to install StormTek Page 10 of 14

11 devices in catch basins that receive drainage from land use types previously identified as generating relatively large volumes of trash. These include commercial and multi-family residential land uses, schools, and bus stops. Approximately 35 catch basin inserts will be installed in these types of areas within the two cities. The second objective is to develop trash loading rates for areas believed to be generating relatively moderate volumes of trash (e.g., industrial and single-family residential). The remaining catch basin inserts (~45) will be installed in locations with these land use characteristics. To better characterize the area draining to each catch basin where a StormTek device will be installed, the following information is being documented: Size of area draining into catch basin; Percentage of each land use within the drainage area, including roads; Presence of bus or train stops; Presence of improper container management (e.g., overflowing dumpsters or trash receptacles); and Presence of other sources. 3.5 Data Collection Methods After installation, the basins will be visually inspected after each of the first 3 storm events (>0.25 ). Most of the catch basins within the two participating cities are small (approximately 24 w X 24 d X 26 h) and may rapidly fill with debris. Therefore, frequent inspections at the onset will be necessary to determine the required maintenance frequency and volume/type of trash captured. Following these initial inspections, the frequency of inspection may be re-evaluated. At each visual inspection, the information on the Standard Catch Basin Inspection/Cleaning Data Collection Form (Data Collection Form) in Appendix A will be recorded. Public works crews will maintain the devices by vactoring the basins and cleaning screens as needed. At each maintenance event, information will also be recorded on the Data Collection Form. All data will be tabulated in Excel and managed by Program staff. 3.6 Data Analysis Techniques Following the completion of the Pilot Study, all data will be compiled into a single database. Data will be used to answer the management questions described in Section 3.1. Specifically, trash volumes captured will be used to assess temporal and spatial patterns and develop preliminary trash loading rates for land uses. In addition, maintenance frequency and cost estimates will be developed to assist future trash implementation activities. Data will be presented graphically and in tabular formats. 4.0 PILOT STUDY SCHEDULE All StormTek devices are expected to be installed no later than spring Data will be collected throughout two wet weather seasons (FY and FY ) and one dry weather season (2008) to characterize wet and dry weather loading rates. An update will be reported within the Program s FY Annual Report. A final report will be developed following the completion of the Pilot Study. Page 11 of 14

12 5.0 REFERENCES Los Angeles Water Board (2007). Amendment to the Water Quality Control Plan Los Angeles Region to incorporate the TMDL for Trash in the Los Angeles River Watershed. August 9, Page 12 of 14

13 Appendix A Standard Catch Basin Inspection/Cleaning Data Collection Form Page 13 of 14

14 Standard Catch Basin Inspection/Cleaning Data Collection Form Date: Time: City: I. CATCH BASIN INFORMATION Inlet #: Block Map #: Street: Cross Street: II. ACTIVITY Inspection Cleaning Both Time Spent Inspecting/Cleaning: minutes III. III. IV. WEATHER CONDITIONS (Check all that apply) Rain Clear Other: Heavy Rain Drizzle Cloudy Windy REASON FOR INSPECTION/CLEANING Initial Follow-up Routine Response to Complaint INSPECTION OBSERVATIONS Other: 1. Material Observed (Provide Percentage Observed): Leaves Grass Sediment Paper Plastic Metal Other: 2. Approximate Depth to Debris/Material: inches 3. Percentage of Catch Basin Full: 4. Needs Maintenance? Yes No If Yes, What? 5. Functioning Correctly? Yes No If No, Why? 6. Needs Cleaning? Yes No 7. Evidence of Bypass? Yes No 8. Is Catch Basin Accessible? Yes No If No, Why? Can t Open Vehicle Other: 9. Additional Comments/Notes: V. CLEANING/MAINTENANCE ACTIVITIES 1. Describe Cleaning Activities: 2. Return Inspection Needed? Yes No Comments 3. Priority for Reinspection: High Medium Low 4. Additional Comments/Notes: Page 14 of 14