Historically Bay Area stormwater programs such as County Watershed Program (CWP) were not charged with monitoring urban runoff. This is because in the past it was believed that the majority of sediment which carries pollutants of concern like mercury, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and polybrominated diphenyl ethers (PBDEs), reach the San Francisco Bay and Delta Estuary from the Central Valley.
However, recent years of Regional Monitoring Program studies by the San Francisco Estuary Institute have found a larger percentage of pollutant loads than previously expected are coming from stormwater/urban run-off flowing to the Bay from smaller, local watersheds. For example, ten years ago, a draft of the Mercury Total Maximum Daily Load (TMDL) report summarized existing data, which suggested that 70% of the mercury entering the bay came from the Central Valley, with only 20% coming via urban stormwater. Visit the Office of Environmental Health Hazard Assessment (OEHHA) for statewide fish advisories and this easy to use Guide to Eating San Francisco Bay Fish and Shellfish (PDF).
In early 2010, CWP joined with several other members of the Bay Area Stormwater Management Agencies Association (BASMAA) to participate in a regional collaborative effort to coordinate water quality monitoring required by the MRP. BASMAA is a 501(c)(3) nonprofit organization comprised of the municipal stormwater programs in the San Francisco Bay Area. The resulting regional monitoring collaborative is called the BASMAA Regional Monitoring Coalition (RMC).
To further assess what's going on, Section C.8 - Water Quality Monitoring of the Municipal Regional Permit (MRP), requires municipalities undertake monitoring for a variety of pollutants in stormwater to get a better a picture of how stormwater contributes pollution to creeks, the delta, and the bay. CWP is working cooperatively through the Contra Costa Clean Water Program and our MRP East County co-Permitees represented by the BASMAA RMC to undertake various water quality monitoring projects, special studies and pilot programs within waterways in both the San Francisco Bay and Central Valley Waterboard regions.
Here are some of the Pollutants of Concern (POC) monitoring activities CWP is currently engaged in:
- Status and Trends (Regional design commencing in Spring 2012)
- Regional Monitoring Program (Bay Area)
- C.11 Mercury & C.12 PCB by Clean Watersheds for a Clean Bay (CW4CB)
- POC & Long Term Monitoring