Copper is toxic to fish and other aquatic life, even in very small amounts. Everyday sources include copper-based chemicals for pools/spas/fountains, copper roofs and building features, and copper-based car brake pad dust in the streets. To protect local creeks and San Francisco Bay, Santa Clara Valley cities and other agencies work together to manage copper in local watersheds.
Regulations, State Actions, Studies
- US Federal Clean Water Act — Prohibits certain discharges of stormwater pollutants, including copper, except in compliance with the National Pollutant Discharge Elimination System stormwater and wastewater management permits.
- California Department of Pesticide Regulation — controls on coppers in pesticides and antifouling paints.
- California Water Board Programs — Nonpoint source pollution monitoring and other control efforts.
- Water Quality Control Plan for the San Francisco Basin — The San Francisco Bay Regional Water Quality Control Board identified several ways to control copper and other sources of pollution in the Bay.
- Copper Sources and Management Strategies Clearinghouse — SCVURPPP’s copper clearinghouse describes copper sources and provides information on best management practices for stormwater programs and publicly-owned treatment works.
Sources of Copper
Copper is an element that exists naturally in the Earth’s crust. It is an essential nutrient for all plants and animals in low concentrations, but in higher concentrations, copper is toxic to aquatic organisms. Chronic exposure to copper can affect the survival, growth, reproduction, brain function, blood chemistry and metabolism of fish and other living organisms.
Natural sources of copper in aquatic systems include geological deposits, volcanic activity, and weathering and erosion of rocks and soils. [Human] sources of copper include mining activities, agriculture, metal and electrical manufacturing, sludge, … pesticide use and more.US EPA Aquatic Life Criteria
In the urban environment, copper is found in certain pesticides, some algaecides for pools/spas/fountains, eroded soils, historic roofs and building features, and copper-based car brake pad dust in the streets.
SCVURPPP and member agencies have addressed and continue to
address copper pollution in several ways, including:
- Managing waste from cleaning & treating copper building features
- Controlling discharges from pools, spas and fountains that have copper-based chemicals
- Inspecting industrial and commercial sites for proper copper controls
- Partnering with manufacturers to lower/eliminate copper content in products such as brake pads
- Educating inspectors and sites on best management practices
Managing Copper in Sediment
Sediment control efforts for reducing PCBs and mercury also contribute to copper reductions. This includes municipal street sweeping, inlet maintenance, and construction/landscaping practices to reduce sediment and erosion.