Drainage Areas


The Flood Control and Water Conservation District uses Drainage Areas as a primary method of planning and implementing flood control facilities.  Funding of a Drainage Area (DA) projects is primarily through development fees.


The Drainage Area Fee Ordinances are enacted by the County Board of Supervisors as the governing body of the Flood Control District. It requires payment of the Drainage Area Fees (PDF) before the filing of the Final Map.

Fees are paid to the FCD directly, or via cities per Fee Collection Agreements. Fees are based on the cost of the proposed Drainage Area improvements and the expected new impervious surface created by the General Plan build-out.

The Watershed Planning and Engineering Section performs the DA fee studies and prepares the engineer's report for the DA fee ordinance. The Current Development Section calculates the drainage area fees.

Drainage Areas:

  • Provide flood protection planning for future development
  • Provide multi-jurisdictional planning of major drainage systems
  • Allows management of major drainage infrastructure as it develops

In Contra Costa County, a Drainage Area (DA) is a legally formed entity with a:

  • Legal Boundary Map
  • Land Use Map
  • Hydrology Map
  • Drainage Area Plan
  • Fee Ordinance