Clean Water Program

Fish from San Francisco Bay contain concentrations of mercury, PCBs, and other chemical contaminants that are above thresholds of concern for human health. This problem was first documented in 1994 when the San Francisco Bay Regional Water Quality Control Board (SFBRWQCB) performed a pilot study to measure contaminant concentrations in Bay sport fish (Fairey et al. 1997).

This page presents sediment chemistry thresholds for seven different contaminant classes, used by the Dredged Material Management Office (DMMO) for determining when bioaccumulation testing will typically be required for dredged material proposed to be discharged at unconfined open water disposal sites in San Francisco Bay. These same thresholds are also used by DMMO to determine when additional analysis of the post-dredge sediment surface (“residual” or “z-layer” sediments) may be warranted.