BoatUS is encouraging boaters in California to contact their lawmakers about Senate Bill 623, which, if passed, will ban copper antifouling paint for recreational boats.

Also known as bottom paint, the brushed, rolled-on or sprayed-on coatings contain copper, an effective biocide that prevents marine growth such as barnacles, seaweed and other organic matter on a boat’s hull or bottom, BoatUS said. If left alone and without any preventive measures, the marine growth can substantially increase fuel consumption, reduce steering ability and eventually render a boat inoperable.

California Senate Bill 623 has passed two committees and is headed for a vote in the full Senate.

As written, the bill says that after Jan. 1, 2015, the sale of new recreational boats with copper bottom paint is prohibited, and that after Jan. 1, 2019, the use or application of antifouling paint containing copper on recreational boats is prohibited.

BoatUS has been monitoring developments in alternative antifouling paints for more than a decade and understands the origins and respects the good environmental intentions of this bill. However, currently there are few effective and cost-conscious alternatives to keep hulls clean,” the group said in a statement.

The March issue of Practical Sailor magazine analyzed 62 antifouling paints, 12 of which had no copper. In terms of performance, one non-copper bottom paint (that contained zinc) was rated “excellent,” one was rated “fair” and 10 were rated “poor,” BoatUS said.

“Bringing new products to market takes significant lead time and money,” Margaret Podlich, BoatUS vice president of government affairs, said in a statement. “How do we know there will be alternatives that are effective and affordable by the bill’s deadline? We recognize that there are many opinions about this bill and encourage boaters to contact your state senator to express your own views. We support innovation in antifouling paint, and we hope that sustainable solutions for boaters and the environment can be found.”

California boaters can click here to contact their senator.