The Santa Ana Regional Water Quality Control Board (Water Board) adopted Resolution R8-2022-0012, amending the Water Quality Control Plan for the Santa Ana River Basin (Basin Plan) on December 2, 2022. The State Water Resources Control Board approved the amendment under Resolution 2025-0023 on August 5, 2025.

The amendments will supersede United States Environmental Protection Agency's technical Total Maximum Daily Loads (TMDLs) for copper that were established as part of the TMDLs for toxic pollutants in 2002 for San Diego Creek and Newport Bay. The Cu TMDLs include dissolved copper targets (the California Toxics Rule criteria for copper) and a sediment numeric target, as well as an alternative sediment target that may be used instead of the sediment numeric target. The Cu TMDLs also include an implementation plan with a compliance schedule.

History

1. New section summarizing amendment to basin plan filed 4-28-2026; amendment approved by State Water Resources Control Board Resolution No. 2025-0023 on 8-5-2025; amendment approved by OAL pursuant to Government Code section 11353 on 4-28-2026 (Register 2026, No. 18).