Commercial Rates

Commercial properties are charged the sewer service fee based upon actual winter water usage as reported by MMWD for the billing cycle ended in either January or February of the prior year. The calculation utilizes and average gallon per day for residential usage to convert the MMWD usage into EDUs.

The 5-year rate plan for Annual Sewer Service Charges was adopted in June 2019. The new commercial rates, effective July 1, 2021, follow below.

Commercial Rates


  • Ross Valley (FY 2019/20) - $1,083
  • Larkspur Rate (FY 2021/22) - $1,529


  • Ross Valley (FY 2019/20) - $2,499
  • Larkspur Rate (FY 2021/22) - $3,513

Annual Sewer Service Charges - Adopted June 19, 2019.