Statewide Mercury Program
Addressing Mercury in California's Waters
Mercury is negatively impacting the beneficial uses of many waters of the state by making fish unsafe for human and wildlife consumption. Although mercury occurs naturally in the environment, concentrations of mercury exceed background levels because of human activities. Gold and mercury mines and atmospheric deposition are the predominate sources of mercury, with minor contributions from industrial and municipal wastewater discharges and urban run-off.
State and Regional Water Board staff is developing a statewide water quality control program for mercury (statewide mercury program or program) that will include: 1) mercury control program for reservoirs; and 2) mercury water quality objectives.
The timeline, below, has links to additional information for both parts of this program.
Statewide Mercury Control Program for Reservoirs
The Statewide Mercury Control Program for Reservoirs will address the 74 currently identified mercury-impaired reservoirs as well as other reservoirs that are identified as mercury-impaired in the future.
NEW! Appendix A: Importance of Primary and Secondary Production in Controlling Fish Tissue Mercury Concentrations will be appended to the Statewide Mercury Control Program for Reservoirs technical staff report, currently under development. Appendix A describes the scientific basis of the mercury conceptual model and linkage analysis, which will be fully described in the technical staff report. Appendix A will be submitted to formal scientific peer review together with the technical staff report.
NEW! For more information on mercury sources in California, an explanation of how mercury accumulates in the food chain, and an analysis of factors affecting methylmercury accumulation in reservoir fish, refer to our Fact Sheet (2013 Fact Sheet).
Statewide Mercury Water Quality Objectives
The State Water Board is developing water quality objectives to protect humans and wildlife that consume locally caught fish. The objectives will likely be expressed as a methylmercury concentration in fish tissue. These objectives will inform mercury policy, mercury pollution prevention plans, and water quality permits. They will apply to California’s inland surface waters, enclosed bays, and estuaries.
This timeline shows the development of the Statewide Mercury Program. The presentation materials from the listed events, including the CEQA scoping documents and comment letters, are available for your review.
Other Mercury Related Programs