County staff warns invasive mussels could cripple Clear Lake infrastructure and drinking-water systems

Staff presented the biological and infrastructural risks of invasive mussels and said prevention is cost‑effective compared with long‑term infestation management. "Both adult mussels and the larval stage, which is known as veligers, can be moved between water bodies... It only takes a few veligers to be able to start a new population," Thomas Fardig said.

Fardig and other commenters described direct threats: clogged intake pipes and pumps, encrusted propellers and docks, potential reduction in property values, and increased water‑treatment costs. Tom Lasik and Greg Giusti, among public commenters, emphasized Clear Lake's high calcium and nutrient levels and warned that low oxygen alone will not prevent mussel establishment. Staff said yearly mitigation costs in impacted regions can run into the millions and that early detection and rapid response planning are central program elements.