MENDOCINO CO., 9/19/26 — Sonoma Water, which used to be known as the Sonoma County Water Agency, and which provides water to parts of Sonoma and Marin counties, will keep inspecting every boat that launches at Lake Mendocino for two more years, after its board voted Sept. 15 to accept a $400,000 state grant.
The grant from the California State Parks Division of Boating and Waterways pays for watercraft inspections and early detection work through Oct. 15, 2028, Sonoma Water said in a press release. The previous state grant, also $400,000, ran out Sept. 15, the day of the vote, according to a 2024 release from the agency.
The vote follows a close call at Lake Sonoma. On June 26, a trained mussel detection dog alerted inspectors to a wakeboard boat trying to launch there, the release said. Inspectors saw no mussels, but they turned the boat away and told the owner to have it professionally decontaminated. A water sample from the boat later came back from the lab with results consistent with the biological markers of golden mussels, according to the release.
Golden mussels were first found in North America in October 2024 at the Port of Stockton, according to the California Department of Fish and Wildlife. They have since been found in the Sacramento-San Joaquin Delta and other California waterways.
“Keeping invasive mussels out of Lake Mendocino protects one of the region’s most important water supplies and recreational resources,” said Rebecca Hermosillo, chair of the Sonoma Water Board of Directors, in the release. “This grant allows Sonoma Water to continue a proven program that has protected Lake Mendocino from invasive quagga and zebra mussels for more than a decade.”
Every watercraft entering Lake Mendocino has to be inspected before it launches. That includes motorboats, kayaks, canoes and stand-up paddleboards. Staff look over the vessel, ask where it last launched and use a detection dog when one is available. Boaters must arrive with drain plugs out and every compartment drained. Most inspections take three to five minutes, the release said.
Sonoma Water started inspecting boats at Lake Mendocino and Lake Sonoma in 2012 with local money. State grants have helped pay for the program since 2020. The Lake Sonoma program is funded separately from the Lake Mendocino grant.
Golden, quagga and zebra mussels attach to boats and trailers and can live out of water for up to 30 days. Once they are established in a reservoir, they clog water supply and flood control equipment, damage habitat and cost millions of dollars to manage. Recreational boats are the main way they move from one lake to another, the release said.
Boaters can check the Department of Fish and Wildlife’s list of infested water bodies before towing a boat to a new lake. Details on the inspection program are at dontmoveamussel.com.