TOXICS TMDL - COPPER POLLUTION REDUCTION PROGRAMS
Marina del Rey Harbor is currently designated as an “impaired” water body on the 303(d) list issued under the 1972 Clean Water Act. The Clean Water Act established regulations and mechanisms to clean up the Nation’s polluted waterways, which included provisions for Total Maximum Daily Loads (TMDLs). A TMDL puts a limit on the amount of pollutant a receiving water body can accept in order to protect its beneficial uses. In the Marina del Rey Harbor, a Toxic Pollutants TMDL was developed by the Los Angeles Regional Water Quality Control Board (Regional Board) to set limits on contaminants entering the harbor water column and sediment. The contaminants addressed in the Toxic Pollutants TMDL are summarized in the table below.
|Copper, lead, zinc, chlordane, PCBs, total DDTs, and p,p’DDE
|Dissolved copper and PCBs
Dissolved copper is a major issue in the Marina del Rey Harbor as well as other marinas along the coast. The leading cause of dissolved copper pollution in marinas is from copper-based antifouling paints. Antifouling paints are used to prevent marine growth on surfaces, particularly boat hulls, yet the majority of these antifouling paints contain copper that leaches into the surrounding water causing pollution issues. The Toxics TMDL regulates the amount of copper going into the harbor.
The TMDL is enforced through the assignment of waste load allocations and load allocations by the Regional Board to different permittees. The permittees named in the TMDL include the County of Los Angeles, the City of Los Angeles, the City of Culver City, as well as the anchorages and boat owners in the Marina del Rey Harbor.
For more information on the Marina del Rey Harbor Toxics TMDL, visit the Regional Board’s website.
What is the County doing to remedy the copper issue?
HULL PAINTS & COATINGS
The County is committed to researching alternatives to copper antifouling paints and providing the boating community with useful information for the selection of hull protection products. Marina del Rey boaters are encouraged to choose a non-biocide bottom paint, or a bottom paint that falls in the lowest range of low leach rate copper paints. Since 2017, the County has been particularly focused on studying the effectiveness and economic feasibility of non-biocide hull paints and coatings. Non-biocide hull paints do not contain metals or other toxic chemicals that leach into the water. Using zinc or organic biocide paints (e.g. Econea), which do not contain copper, could also help to reduce copper loading in Marina del Rey Harbor.
IN-WATER HULL CLEANING BEST MANAGEMENT PRACTICES
The County passed an ordinance that requires in-water hull cleaners to use best management practices (BMPs) for all in-water activities. Using BMPs during in-water hull cleaning has been shown to dramatically reduce contaminant loading of pollutants such as copper to the water column and sediment from boat hull paints.
IN-WATER DRY DOCKING SYSTEMS
An in-water dry docking system works by separating the hull of the boat from the water without lifting the boat out of the water. Unlike a typical ‘wet’ slip liner, an in-water dry dock removes the water from between the boat and liner to keep the hull dry when docked. In-water dry docks are a promising new strategy to reduce copper pollution in marina waters and save boat owners money over the long term, since a boat docked in an in-water dry docking system does not need antifouling hull paint (which typically contains copper or other biocides) or regular hull cleaning. These devices protect the hull from damage and electrolysis and do not require antifouling paint. An in-water dry dock is being tested by a private boat owner at Anchorage 47 and is visible from the promenade.
Boat lifts are devices used to raise a boat out of the water while it is docked in a slip. They help protect the boat from marine growth, corrosion, and other potential damage, such as electrolysis. Boat lifts can be used as an alternative to antifouling paints to prevent algae, barnacles, and other encrusting organisms from developing on the hull by keeping the boat out of the water while in the slip. There are several brands of boat lifts in use in the Marina del Rey Harbor.
The County has completed several special studies to better understand the Marina del Rey Harbor’s physical, chemical and biological processes related to water quality. Additional special studies are planned or in the process of being completed.
If interested in learning more about the County’s copper reduction programs, you can email the program contact by filling out the fields below.
You may also join our new boater outreach email list, which the Department of Beaches and Harbors will utilize for program updates, new programs, requests for feedback, and other outreach in an effort to have more direct communication with the Marina del Rey boating community.
We look forward to speaking with you!