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Public Works will re-open our front counter to the public on July 6 and start providing some modified services.  Our hours will be 8 – 5, with closure from 12 – 1:30 for sanitation. Masks are mandatory in our building, and we ask that you adhere to physical distancing protocol. We will have limited services at our front counter and will not be accepting drop in meetings.  Please contact 805-781-5252 to make an appointment with staff.  Bus passes can be purchased at the Kiosk on the corner of Osos and Palm or by phone via Follow us on Twitter @SLOCountyPWD for the latest updates.

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Public Works

County of San Luis Obispo

Lake Nacimiento Mussel Inspection Program

Mandatory vessel inspection required prior to launching!

Please practice responsible boating by ensuring that your watercraft is CLEAN, DRAINED, DRY, and MUSSEL-FREE before launching.

Per the Quagga and Zebra Mussel Prevention Program Standards, all vessels that have been on an infested waterbody in the last 30 days will not be permitted to launch at Lakes Nacimiento or San Antonio. All vessels who pass inspection must carry a Vessel Screening Permit while boating. Permits are valid for a maximum of 21 days after Level I screening/inspection. Be sure permit is valid and current before boating.

For a current list of infested waterbodies please visit the California Department of Fish and Wildlife website.

What can you do to prepare your vessel and save time prior to inspection?

  • Inspect all exposed surfaces - small mussels feel like sandpaper to the touch
  • Wash the hull of each watercraft thoroughly
  • Remove all plant and animal material
  • Drain all water and dry all areas, including ballast tanks
  • Drain and dry the lower outboard unit
  • Clean and dry all live-wells
  • Empty and dry any buckets, toys, skis, boating equipment in contact with the water
  • Dispose of all bait in the trash
  • If you've been on mussel-infested waterbodies within the last 30 days you will not be permitted to launch.

These requirements remain in effect until further notice.
Thank you for your help in keeping our local lakes mussel free!

NOTICE: It is unlawful (CA Fish & Game Code Sections 2300- 2302 and SLO County Code Chapter 11.20.120) to possess, import, ship, or transport in the state, or place, plant, or cause to be placed or planted in any water within the state, zebra or quagga mussels.

Please contact the SLO County Mussel Prevention Hotline at (805)788-6006 for the full list of individual private ramp mussel coordinators.


Invasive Mussels
Lake Nacimiento Resident Vessel Program