Central Marin Sanitation Agency

CMSA owns, operates, and maintains the Central Marin regional wastewater treatment facilities on Andersen Drive, next to San Quentin Ridge, in San Rafael. In addition, CMSA provides maintenance services to others and allows for the disposal of hauled wastes from within the CMSA service area, which includes San Rafael and Ross Valley, and for some wastes from areas of Marin County west of the service area. Exceptions may be made on a case-by-case basis by contacting the CMSA main office.

Empty Your Recreational Vehicle Sewage at the Treatment Plant

Procedures:

  1. Stop at the designated point on the plant entrance road.
  2. Come into the CMSA Administration Building to sign-in and complete RV Waste Station transactions.
  3. Proceed to security gate. Once gate opens, follow yellow road striping to the receiving station.
  4. RV users must have at least 10 feet of 3-inch or smaller discharge hose in order to discharge waste to our system.
  5. Non-potable water is available on-site to assist in cleaning our your Grey and Black water tanks.
  6. We ask that you clean up the receiving station prior to leaving CMSA.
  7. A staff member will be available to assist you if there are problems with the receiving station, however, we cannot assist with off loading or any other mechanical issues regarding your vehicle or equipment.

Septic Tank, Portable Toilet, and Restaurant Grease Trap Wastes.

CMSA accepts hauled wastes from portable toilets throughout Marin County, from septic tanks in central and western Marin County, and restaurant grease traps in the CMSA service area. Wastes must be entirely domestic, with no industrial wastes, such as paint, petroleum products, etc. Haulers must make prior arrangements with CMSA to be placed on the list of approved haulers.

For More Information, see the permitting page.

Alternate RV disposal sites:

(These sites are not part of CMSA, you will need to call and verify pricing and hours of use.)

  • Shell Station
    415-897-3739
    7473 Redwood Blvd.
    Novato, CA
    Open 24 hours/day
    Cost: $5 without gas - $3 with gas
  • Marin Park
    415-461-5199
    2140 Redwood Hwy
    Greenbrae, CA
    Mon - Fri 8:00 am - 7:30 pm
    (call ahead for exact hours and price to dump)
CMSA