Stormwater Management

To report illegal dumping or a spill, call:

  • 925-253-4231 (During Business Hours - Public Works General #)
  • 1-800-NO-DUMPING (1-800-663-8674) 
    (After Hours - County Clean Water Program)
  • 925-284-5010 (After Hours if active dumping underway - Non-Emergency Police Dispatch)
  • If you are aware of an emergency and need immediate response call 911.

Clean Water Act

In 1972, the Federal Water Pollution and Control Act was enacted. In 1987, it was amended and is currently known as the Clean Water Act (CWA). In accordance with CWA amendments, regulations require municipalities to obtain National Pollutant Discharge Elimination System (NPDES) permits which outline programs and activities to control surface stormwater pollution.

For municipalities such as the City of Orinda, the type of pollution that must be eliminated or reduced to the maximum extent practicable is called "non-point" pollution, consisting of all types of substances generated as a result of urbanization including but no limited to:
  • Automobile Fluids
  • Fertilizers
  • Litter
  • Pesticides
  • Sewage

Contra Costa Clean Water Program

To comply with these regulations, Contra Costa County, nineteen of its incorporated cities and the Contra Costa Flood Control and Water Conservation District joined together in 1993 to form the Contra Costa Clean Water Program (CCCWP). The CCCWP strives to eliminate stormwater pollution through public education, inspection and enforcement activities and industrial outreach.
Contra Costa Clean Water Program link.

Development Requirements

In February 2003, the RWQCB revised Provision "C.3″ in the NPDES permit governing discharges from the municipal storm drain systems of Contra Costa County. Since August 2006, new and redevelopment projects that create or replace more than 10,000 square feet of impervious area have been required to treat and/or detain stormwater runoff before it is discharged to creeks or storm drains.


Through the Contra Costa Clean Water Program, Contra Costa municipalities have prepared a C.3 Guidebook (7th edition) to assist applicants through the process of submittals and reviews.

Newer Requirements

Since December 2011, facilities to treat runoff will be required for auto service facilities, retail gasoline outlets (gas stations), restaurants, and uncovered parking lots that create or replace as little as 5,000 square feet of impervious area. The threshold for other projects remains at 10,000 square feet.

Starting December 2012, smaller projects creating or replacing 2,500 square feet or more of impervious surface must include at least one feature that directs a portion of runoff from roofs or pavement into cisterns or rain barrels for reuse, directs runoff onto vegetated areas, or includes permeable pavements. Read the C.3.i Requirements (PDF).

Appendix A & K

Appendix A (PDF) to the C.3 Guidebook allows cities, towns or the County to identify any exceptions or additional requirements to the information provided in the C.3 Guidebook. The only additional requirement that the City of Orinda has at this time is that the Stormwater Control Plan shall be prepared and stamped by a professional civil or geotechnical engineer or engineering geologist, licensed by the state of California.

The geotechnical engineer for the project, if not the preparer of the Stormwater Control Plan, shall prepare and sign a letter documenting review and approval of the Stormwater Control Plan.

Appendix K (PDF) of the 3rd edition of the C.3 Guidebook allowed cities, towns or the County to describe Operation and Maintenance (O&M) Verification Program for C.3 facilities. The current edition C.3 Guidebook no longer contains Appendix K, but the information contained therein remains valid.