The District maintains approximately 196 miles of mainline and trunk line sewers and 7.9 miles of force main pipe. In addition, the District owns and operates five major pump stations, and 14 minor pump stations and lift stations. The major pump stations collect and pump flow from the minor stations and trunk lines to the Central Marin Sanitation Agency (CMSA) treatment plant. Sewer laterals - both lower and upper laterals, - are owned and maintained by individual private property owners.
The State Water Resources Control Board (SWRCB) has issued Statewide Waste Discharge Requirements for sanitary sewer systems, which include requirements for development of a Sewer System Management Plan (SSMP).
The State Water Board requirements are outlined in Order No. 2006-0003-DWQ, Statewide General Waste Discharge Requirements for Sanitary Sewer Systems, dated May 2, 2006 (SSO WDR), and amended by Order No. 2013-0058-EXEC, dated July 30, 2013.
The District's SSMP is organized by the SWRCB outline and contains 11 elements designed to meet the state's Sanitary Sewer Overflow Reduction Program requirements. The structure of this document follows the section numbering and nomenclature specified in the state SSMP requirements.