California Lakes with Mussel Inspections: What to Know
Every boater should Clean, Drain and Dry, and motorized boats used in fresh water need DMV's Mussel Fee sticker. Beyond that, each lake runs its own inspection, quarantine, seal or screening rules, summarized here lake by lake from Dockya's pages.
Updated October 8, 2026
Mussel rules in California are set lake by lake. Two things apply everywhere: Clean, Drain and Dry after every outing, and display DMV's Mussel Fee sticker on a motorized boat used in fresh water. Then check the lake's own program, which may mean an inspection, a quarantine, a seal or band, or a screening permit. For the background on golden mussels, see our mussel rules guide.
The statewide basics
- Clean: remove plants, mud and animal material from the boat, trailer and gear before leaving. Drain ballast, bilge and live wells, never back into the waterway. Dry everything before launching somewhere else; waiting periods vary, so ask the lake.
- Mussel Fee sticker: DMV requires it on motorized recreational vessels used in fresh water. As of October 2026 the fee is $16, per DMV, and the sticker goes on both sides of the hull. It is not an inspection pass, and paying it doesn't exempt a boat from local inspections or fees.
Rules change often. Several lakes below changed their programs in 2025 and 2026. Call the lake before you tow.
Southern California
- Big Bear Lake: every vessel, motorized or not, is inspected and needs a Lake Use Permit; decontamination units are at the East Ramp, and free quarantine bands are available.
- Castaic Lake: zero-tolerance inspection, boats must be 100 percent dry, and a failed boat can't launch for 7 days. Castaic Lagoon's page says arrival inspections are discontinued and boats are inspected on exit, so call to confirm.
- Pyramid Lake: all watercraft, including kayaks and float tubes, are inspected before launch, with exit inspections since 2016. Golden mussels were confirmed in September 2025.
- Silverwood Lake: after golden mussels were found in September 2025, arrival inspections stopped; outbound inspections are required and drain plugs must be pulled.
- Lake Perris: a failed inspection means an eight-day quarantine covering Perris, Silverwood and Diamond Valley Lake.
- Lake Skinner: county pages describe a 7-day quarantine after the mandatory inspection.
- Lake Casitas: every vessel is inspected and serves a 35-day quarantine; failed boats can't be reinspected for at least seven days.
- Lake Cachuma: trailered vessels need 30 consecutive days of quarantine before first launch; tags from other agencies aren't recognized.
- Lake Hodges, Sutherland and Lake Cuyamaca: staff or ranger inspection before launch; Cuyamaca doesn't accept other lakes' tags.
- Lake Hemet, Diamond Valley Lake, Puddingstone Lake and Lake Piru: inspection before launch. At Hemet any moisture is an immediate failure, and Piru inspects on entry and exit.
Central Coast
- Lopez Lake and Santa Margarita Lake: since January 1, 2026, ballast boats need a 30-day quarantine and bleach decontamination isn't accepted. Santa Margarita doesn't honor Lopez clear tags.
- Lake Nacimiento: a Vessel Screening Permit, valid 21 consecutive days; decontamination certificates aren't accepted, and failing to show a valid permit can bring fines up to $2,000.
- Pinto Lake: inspection before launch, Friday to Sunday as the City listed it in October 2026; boats recently launched in waters such as Lake Mead, Lake Havasu, Lake Mohave and Lake Skinner are barred.
Bay Area and North
- Lake Del Valle: golden mussels were reported in September 2026; boats launched here are quarantined 30 days from other district waters unless they keep an intact band.
- Lake Berryessa: a free red 30-day seal or hot-water decontamination; a green seal on exit.
- Clear Lake: a Lake County sticker on boat and trailer and a $20 screening fee; visitor stickers expire monthly.
- Lake Sonoma and Lake Mendocino: inspection before launch, paddlecraft included.
- Whiskeytown, Shasta and Trinity: the Invasive Mussel-Free Certification on your windshield. A Forest Order bans possessing or transporting mussels at Shasta and Trinity through December 4, 2027.
- New Bullards Bar: free mandatory screening for motorized boats, with no quarantine.
- Lake Oroville: DWR ended its inspection, decontamination and seal program on April 29, 2026.
Sacramento, Sierra and Central Valley
- Folsom Lake: since April 14, 2025, trailered or motorized boats are inspected, then sealed for 30 days or decontaminated for a green seal.
- New Melones: gas-powered boats need a 30-day out-of-water quarantine with a wire and red seal, or a paid decontamination wash.
- Lake Tulloch: only Tulloch-issued bands, or a same-day New Melones decontamination (one way).
- Camanche: screening, inspection, a 30-day quarantine and a red band; a blue band allows re-entry.
- San Luis Reservoir: exit inspections since October 29, 2024, then a seven-day dry-out before another San Luis SRA lake.
- Modesto Reservoir, Don Pedro and Millerton: inspection or self-inspection permits.
- Donner Lake and Lake Tahoe: Donner needs a self-inspection sticker; every motorized boat on Tahoe needs an inspection or intact seal.
- New Hogan Lake runs random inspections. Pages for Lake Kaweah, Lake Isabella and Lake Almanor list no mandatory program; call before you go.
This guide is general information, not legal advice; rules change, so check the linked pages and posted signs.