MONO COUNTY, Calif. — Beginning April 9, 2026, Mono County will require mandatory inspections for all trailered watercraft prior to launching in local lakes and reservoirs. The new ordinance is designed to prevent the spread of invasive golden mussels, a rapidly emerging threat to California waterways.

Golden mussels were first detected in California in late 2024 and have already shown the ability to spread quickly across a wide range of environments. Unlike other invasive mussel species, golden mussels can survive in colder, high-elevation waters, making the lakes of the Eastern Sierra especially vulnerable.

To protect these fisheries and surrounding ecosystems, Mono County has adopted a Water Vessel Inspection Program that will require all boats to be inspected before entering the water. Boats identified as high-risk may also be required to undergo a decontamination process before launching.

At this time, specific inspection station locations have not been officially released. However, inspections are expected to take place at or near major launch areas, including Crowley Lake, Bridgeport Reservoir, Twin Lakes, the June Lake Loop, and Convict Lake. Boaters should plan for inspections prior to launching and allow extra time, especially during peak fishing periods.

In addition to lake-based inspections, boaters traveling into Mono County may encounter mobile or roadside inspection checkpoints along key travel routes such as Highway 395.

During an inspection, officials will check vessels for standing water, plant material, mud, and any signs of contamination that could transport invasive species. If a vessel is deemed at risk, it may be required to undergo decontamination, typically involving hot-water washing, before it is cleared for launch.

Mono County officials continue to urge all anglers and boaters to follow the “Clean, Drain, and Dry” protocol every time they leave a body of water. These preventative steps remain one of the most effective ways to stop the spread of invasive species.

The new inspection requirement comes just ahead of the busy spring and summer fishing seasons and is expected to impact launch procedures across the region. Boaters are encouraged to stay informed and check for updates as additional details, including inspection station locations and hours of operation, are released.

For more information, go to EasternSierraWID.com.