Advisory committee endorses workplan for study revisiting copper TMDL in Marina del Rey Harbor

A technical advisory committee has endorsed the draft workplan for a study that will examine whether existing regulatory targets for dissolved copper in Marina del Rey Harbor should be modified to more accurately reflect the ecological threat posed by copper.

At an all-day meeting in December, the committee concluded the workplan was appropriate to accomplish the study’s goal and recommended enhancements to the study’s sampling design to improve representativeness and accuracy of the results.

The two-year study, led by SCCWRP, will document the concentrations of copper that aquatic organisms in the Los Angeles County boat harbor are exposed to at different times of the year, and how toxic these copper levels are at different sites across the harbor.

Under the harbor’s existing Total Maximum Daily Load (TMDL) regulatory target, Marina del Rey Harbor is required to reduce copper loading by 85%, which would require boat owners to make significant changes to the types of anti-fouling paint they typically use on the underside of boats.

The technical advisory committee is scheduled to release a report on its recommendations in February; the committee’s report will include responses to stakeholder comments about the study workplan.