Nontoxic Antifouling Strategies for Boats Leigh Taylor Johnson & Jamie Anne Miller UC Sea Grant Extension Program San Diego County

University of California Sea Grant Extension Program 7 Marine Advisors and 1 Specialist Enhance understanding, conservation, sustainable use of nation’s coastal and marine resources Direct link for communication between university, industry, and public Applied research and education to assist policy makers and stakeholders in making wise decisions on issues affecting coastal and marine resources Water quality focus in San Diego County Improve water quality and maintain viable boating industry CA boating industry worth $11 billion in 1995

Copper-Based Antifouling Paints Designed to release copper into surface waters to prevent organisms from growing on boat bottom Crowded boat basins with low circulation Copper builds up in water column and sediment and can reach toxic levels Regulations to reduce dissolved copper levels are being planned

Elevated Dissolved Copper Levels Harmful levels of dissolved copper detected in boat basins Exceed federal and state standards of 3.1 ppb San Diego Bay, Dana Point Harbor, Oceanside Harbor, Newport Bay, Marina Del Rey TMDLs San Diego Bay, Newport Bay, Marina Del Rey Boatyard discharges in Santa Barbara and Morro Bay Affects growth, development, reproduction, survival at various life stages of: mussels, oysters, scallops, crustaceans, sea urchins 95% of dissolved copper comes from passive leaching by antifouling paints

International Issue Copper-based bottom paints banned in Netherlands and east coast of Sweden Nontoxic Antifouling Strategies Conference in 2000 attracted international audience Presented technical, environmental, and regulatory aspects of issue Stakeholders developed recommendations presented to state and local officials

Nontoxic Bottom Paint Demonstration Project Funded in part by US EPA and California State Water Resources Control Board Purpose to help boat owners make decisions about nontoxic antifouling strategies Tracked performance of silicone, epoxy, and ceramic-epoxy coatings on 6 recreational boats in San Diego Bay Underwater hull cleaners report: coating conditions fouling growth levels diver effort levels type of cleaning tools used

Nontoxic Bottom Paint Characteristics Must be able to withstand more frequent and possibly more aggressive cleaning May last long enough to make up higher application costs and twice as frequent hull cleaning Epoxy coatings are durable and are expected to last many years Silicone coatings are “fouling release” when vessel exceeds certain speed (20 knots often cited)

Demonstration Project Results Epoxy Coating (sail) Almost 5 years old; 2 more years expected Coating condition rated at 3 out of 5 Coating smoother as wears down from cleaning After one year: Epoxy Coating (power) Nearly new condition Some wearing on edges Surface lightly etched Ceramic Epoxy Coating (sail and diesel-electric) Minor scarring from calcareous fouling growth Coating has sheen but no shine

Sea Grant Extension Program Demonstration Project Field Days Educate boating community on nontoxic alternatives to copper bottom paints Opportunity for attendees to: View hull cleaning of project boats with underwater camera Speak to boatyard, underwater hull cleaner, paint company, Sea Grant representatives View project boat bottoms out of water

Senate Bill 315 Directed California Department of Boating and Waterways to fund study of incentives for boat owners to switch to nontoxic alternatives UC Davis Center for Pest Management, Research, and Education also supported study Collaborative effort Sea Grant Extension Program of San Diego County UCSD Department of Economics Purpose of study Identify incentives for boaters to switch to nontoxic alternatives

Economic Incentives Study Surveyed 200 boaters in San Diego Bay Use of antifouling coatings Frequency of re-coating and stripping of copper paint Willingness to pay for nontoxic coating Awareness of availability of nontoxic paint Surveyed boatyard, under water hull cleaner, marina manager, paint company representatives Collected costs on application and maintenance of nontoxic coatings

Comparison of Costs Hull maintenance costs include Cost to prepare hull and apply coating Cost of hull coating Frequency coating needs to be applied How often coating needs to be stripped Hull cleaning frequency Compare costs over total lifetime of boat: copper versus nontoxic coatings

Survey Results Copper-based paints Nontoxic Paints Less expensive to apply Cleaned about every 4 weeks Re-applied every 2.5 years Stripped every 6th application (every 15 years) Nontoxic Paints More expensive to apply Cleaned about every 2 weeks May last 5-10 years or more May never need to be stripped (San Diego boat has had epoxy coating almost 5 years; expect 2 more) Won’t adhere to copper paint

Economic Study Finding Most effective candidates for nontoxic paint: New boats Boats that need to be stripped of old copper paint Requiring new boats to use only nontoxic paints will begin the phase-out of copper Announcing a future ban will increase nontoxic hull value and encourage boaters to switch

Boatyard Capacity Constraints Quickest time to phase out copper paint in San Diego Bay is 7 years for $20 million Least cost policy to phase out copper paint in San Diego Bay is 15 years for $1 million Significant difference Allows newest existing boats painted with copper to go the typical 15 years before paint is stripped **Nontoxic paint can not adhere to copper paint**

Looking to the Future UCTV Documentary Project evaluation and results extended Present seminars to state, regional, and local associations of boat owners and boating businesses Review of other nontoxic or less toxic antifouling strategies being developed (based on funding availability)

Questions and Comments Thank you!