The purpose of the CW4CB project was to contribute to the development of a comprehensive regional strategy for reducing PCB and mercury loads in urban runoff. To meet this goal, a number of priority urban stormwater-related actions required by the Bay TMDLs and the first term MRP (issued in 2009) were implemented as part of the CW4CB project.
CW4CB had four key tasks, the first three of which were field studies in selected watersheds surrounding the Bay, with a focus on old industrial areas with elevated pollutant levels. The studies aimed to evaluate, on a pilot scale, a variety of potential methods to reduce the amount of PCBs and mercury conveyed to the Bay via urban runoff. Since PCBs and mercury are mainly found attached to sediments in the urban environment, these methods focused on containment or removal of polluted sediment. The fourth task was an outreach program to targeted communities.
Urban Runoff Treatment Retrofits: El Cerrito Green Streets Bioretention - Eureka
Enhanced Municipal O&M: Storm Drain System Cleaning and Video Inspection
Recipient: Bay Area Stormwater Management Agencies Association (BASMAA)
Funding: USEPA Region IX San Francisco Bay Water Quality Improvement Fund - $5,000,000 (non-federal match= $1,940,000)
Project Period: May 3, 2010 – May 2, 2017
Partners: California Department of Health Services, Alameda County Flood Control and Water Conservation District, and the cities of Oakland, Richmond, San Carlos, San Jose, and Vallejo.
Environmental Results Summary: Clean Watersheds for a Clean Bay Project: Implementing the PCB TMDL
OUTPUTS (Activities, efforts, and/or work product during project period)
- Select five high priority subwatersheds that discharge urban runoff with PCBs and other pollutants to the Bay
- Identify PCB and mercury source areas within the project subwatersheds and refer these sites to regulatory agencies for cleanup and abatement
- Develop methods to enhance removal of sediment with PCBs and other pollutants during municipal sediment management activities
- Retrofit 8 to 10 urban sites with stormwater treatment facilities
- Facilitate development and implementation of a regional risk communication and exposure reduction program that focuses on educating the public about the health risks of consuming certain species of Bay fish that contain high levels of PCBs and mercury
- Create public education outreach materials, project web portal, guidance manual, and technical workshops
OUTCOMES - SHORT-TERM (1-5 year environmental results)
- Reduce annual loading of PCBs to the Bay by approximately 0.3 - 1.5 kg per year, reducing the current estimated stormwater runoff load
- of 20 kg/yr by about 2-8%
- Treat ~ 2 square miles with stormwater retrofits to reduce potential hydrologic impacts on downstream receiving waters
- Consumers of Bay fish will have a greater awareness and understanding of fish contamin-ation issues and options for reducing their exposure to pollutants
OUTCOMES - LONG-TERM (5-20+ year environmental results)
- Identify most promising best management practices (BMPs) for fully meeting the PCB TMDL allocations (2 kg/year) in the future and thereby help address important impairments to the Bay’s beneficial uses
- Enhance the desirability of commercial enterprise zones and residential neighborhoods in the project watersheds as a result of clean-up activities