Copper Reduction

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

Copper roof features, more common on older buildings (Photo by W. Carter, Wikimedia creative commons)

Sources of Copper

Copper is sometimes present in swimming pool treatment chemicals (Photo by M. Van Den Heuvel, Unsplash)

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.


Copper Reduction Documents

1/1/2012Requirements for Copper Roofs and Other Architectural CopperFact Sheets,
12/3/2004Copper Sources and Management Strategies ClearinghouseGuidance Documents
5/20/2004Is Your Roof Runoff Polluted?Fact Sheets
5/1/2004Draining Pools and SpasFact Sheets
5/1/2003BACWA – Guidelines for Plumbers and Installers of Copper Piping SystemsFact Sheets
1/1/2003BACWA – Guidelines for Designers of Copper Piping SystemsFact Sheets
3/1/2001Architectural Uses of CopperReports
1/1/1997Copper Piping Corrosion: A Problem for San Francisco BayReports