California battles EPA over biofouling authority

California’s efforts to manage aquatic invasive species face a new challenge as the California State Lands Commission has initiated legal action against the United States Environmental Protection Agency (EPA).

The California State Lands Commission filed a petition for review concerning the EPA’s final rule issued under the Vessel Incidental Discharge Act (VIDA), arguing it unlawfully overrides the state’s established biofouling management programme.

The dispute arises from the EPA’s October 2024 publication of Performance Standards regulating vessel discharges, including biofouling management.

The California State Lands Commission contends these federal regulations unlawfully pre-empt California’s stronger state standards, which have been instrumental in managing aquatic nuisance species along its coasts. It argued "over 60% of the currently established aquatic nuisance species in the State’s coastal and estuarine waters were first introduced through biofouling".

It warned the EPA’s weaker, largely self-regulated framework for vessel biofouling management could substantially undermine California’s ability to protect its waterways, economy, and public health.

At the heart of the California State Lands Commission’s case is the claim the EPA has exceeded its statutory authority under VIDA. It stated, "under the plain language of the statute, biofouling…is not a ’discharge’ at all subject to regulation under VIDA".

Consequently, California asserts the EPA cannot claim pre-emption over state biofouling regulations, which were developed through years of scientific study and practical enforcement.

California’s Marine Invasive Species Program, managed by the California State Lands Commission, mandates rigorous vessel inspection, reporting and management practices for biofouling. In contrast, the EPA’s new rules largely delegate compliance to vessel operators’ self-created management plans, with limited enforcement mechanisms.

The California State Lands Commission warned the shift to weaker federal standards could allow "inwater cleaning of vessels with only microfouling without capturing and treating the effluent," risking the release of copper-based antifouling coatings into harbours already struggling with pollution levels above Clean Water Act thresholds.

The California State Lands Commission has long opposed VIDA. It objected during the Act’s legislative process and again during the EPA’s rulemaking, submitting multiple comment letters.

Despite these efforts, the EPA proceeded with a rule that, according to the California State Lands Commission, “dismantles California’s Marine Invasive Species Program" by stripping the state of the authority to maintain or develop its own, stricter biofouling regulations.

The EPA’s rule will not come into full force until the United States Coast Guard finalises its implementing regulations, expected by October 2026. However, the California State Lands Commission’s legal action aims to pre-emptively prevent the federal standards from taking effect in California’s jurisdiction.

In addition to California’s petition, the EPA has faced broader scrutiny over its implementation of VIDA. In 2023, environmental groups including the Center for Biological Diversity and Friends of the Earth sued the agency for failing to meet statutory deadlines to establish national discharge standards.

That case resulted in a consent decree obliging the EPA to finalise the required regulations by late 2024.