ACWD escalates invasive species defense against Golden Mussel threat

ACWD escalates invasive species defense against Golden Mussel threatThe board approved 2026 prevention programs amid warnings that the rapidly spreading Golden Mussel may force the district to reconsider recreational boating access to protect infrastructure.

Board authorized agreements for 2026 Invasive Mussel Prevention programs at Quarry Lakes and Lake Del Valle.

Directors identified the Golden Mussel as a 'far more destructive' threat than previous invasive species, citing clogged screens in the Delta.

Staff confirmed a new contract with a consultant to develop a response plan in coordination with Zone 7 and Valley Water.

Board members discussed the potential need to ban boating, following East Bay MUD’s example, as inspection protocols face challenges from contaminated fishing gear.

At its December 11 meeting, the Alameda County Water District (ACWD) Board of Directors authorized agreements for 2026 Invasive Mussel Prevention programs at Quarry Lakes Regional Recreation Area and Lake Del Valle. The decision comes as the board acknowledges the emerging threat of the "Golden Mussel," which Director Weed described as "far more destructive" and spreading more rapidly than quagga or zebra mussels. Director Weed noted reports from the Association of California Water Agencies (ACWA) conference indicating that Contra Costa had experienced screens "literally clogged in the delta" due to the species. Concerns were raised regarding the efficacy of traditional boat inspections, with Director Weed observing that mussels are increasingly found in fishing gear and tackle boxes, which are harder to supervise than boat hulls. Consequently, the board discussed the potential necessity of limiting recreational access. Director Sethi suggested staff investigate limiting boating activity, pointing to the East Bay Municipal Utility District (EBMUD) as a precedent. EBMUD implemented a ban on private vessels which effectively prevented golden mussel detections through late 2025, though that district is now transitioning to limited reopenings with stricter quarantine protocols. In response to these concerns, General Manager Ed Stevenson confirmed that the district signed a contract earlier in the week with a consultant to analyze the issue and develop a plan. This consultant is also working with regional partners Zone 7 Water Agency and Valley Water. Staff member Ms. Heidis added that the district is tracking research from the Department of Water Resources (DWR) regarding potential treatment options.