Baykeeper Update

Stopping Copper Pollution in San Francisco Bay

Baykeeper is advocating for stronger regulations on boat coatings to protect fish and other wildlife from the toxic effects of copper contamination.

Copper is a powerful biocide commonly found in specialized boat coatings that prevents algae, barnacles, and other sea life from growing on boat hulls. These “anti-fouling” paints are widely used by both commercial and non-commercial boaters to prevent sea life from attaching to boat hulls, where they can damage the hulls and decrease a vessel’s speed.

Unfortunately, this leads to excessive copper in waterways, where it hurts wildlife. Copper is a heavy metal that is harmful to fish, mussels, and other aquatic lifeforms that live in or migrate through San Francisco Bay. Chronic exposure to excessive copper can interfere with wildlife reproduction and growth, and even lead to death.

Boat hull coatings containing copper leach into the surrounding waters, leading to toxic hot spots near marinas and ship maintenance facilities. The water near most California marinas is already contaminated with excessive copper.    

To help curb this contamination, the California Department of Pesticide Regulation recently proposed to limit the amount of copper released by boat coating products. However, the limit is not stringent enough to protect fish and other wildlife.

Baykeeper is urging the department to set stronger copper limits than those proposed for products for both commercial and non-commercial vessels. Agency officials should also consider the use of less harmful alternatives to copper-based products.   

San Francisco Baykeeper has a unique perspective on this particular issue; several years ago, we repainted the Baykeeper patrol boat using a non-copper paint. Our staff scientist did extensive research on low-toxicity coating products, and we opted for a zinc-based paint that contains a lower concentration of the metal and is less toxic than copper.  

Leading our partners San Diego Coastkeeper and Los Angeles Waterkeeper, San Francisco Baykeeper will continue to push for standards keeping excessive copper out of our waters—for the health of fish and wildlife in the Bay and along the California coast.  

See Baykeeper’s comment letter, attached, for more details on the state’s new proposal and our position.

Photo by Robb Most