Contra Costa County has 31 major watersheds and sub-watersheds containing more than 1,300 miles of creeks and drainages. Of that total, the County maintains approximately 75 miles of improved creeks and drainages. The rest is the responsibility of private property owners.
The County maintains only those drainage facilities required as a condition of development constructed to standards applicable at the time of construction and located in an easement or other land right accepted by the County. Creek maintenance is the responsibility of the owner whose property abuts a creek.
When the creek area is not properly maintained, the resulting obstructions can lead to increased flooding, changes in the course of the creek, and increased erosion on the obstructed property and/or downstream properties. See Division 1010 of the Title 10 County Ordinance Code for more information on. The Public Works Department recommends the following guidelines on private creek maintenance (PDF).