Wastewater treatment processing is one of the most highly-regulated industries in the nation.  It is designed to remove pollutants to protect public health and local waterways, with pretreatment being an essential component of helping reduce pollutants at their source. 

Delta Diablo’s Industrial Monitoring Department is responsible for regulating the wastewater discharge from business and industry to ensure that hazardous substances (solvents, pesticides, metals, grease, petroleum, etc.) are not discharged into the sewer system.  Part of the regulations include establishing numerical limits for those pollutants that can be discharged into the sewer (known as local limits).  Permits are issued to specific business types, as well as any industry or business that has a potential to exceed local limits. 

The term “pretreatment” means the reduction of the amount of pollutants, or the alteration of the nature of pollutant properties in wastewater prior to, or in lieu of, discharging or otherwise introducing such pollutants in a publicly owned treatment works (POTWs) such as Delta Diablo (40 CFR 403.3).  The pretreatment program at Delta Diablo serves to protect the District’s collection wastewater treatment, recycled water facilities, the Delta, and the safety of its workers by limiting the pollutants discharged into sewer systems.

Special Discharge Permit (SDP).  Delta Diablo issues a Special Discharge Permit for temporary discharge such as construction projects.  SDPs are short term-not to exceed one year.  They are for limited volume, non-standard wastewater discharge of many different types of wastewater or groundwater that meet the special discharge requirements included in the SDP application:

Special discharge permit applications:

Zone 1 (Bay Point) (pdf)

Zone 2 (Pittsburg) (pdf)

Zone 3 (Antioch) (pdf)

General Resources

• District Code (pdf) - The codification of ordinances that have been adopted by the Delta Diablo (District) Board of Directors that define and direct how the District conducts business.  Chapter 2.28 of the Code contains the District's pretreatment regulations, including local limits.
• Baseline Monitoring Report (pdf) - All applicable sites based on the SIC Code listing above are required to submit the Baseline Monitoring Report (BMR) to the District

For additional information, please contact one of our Pretreatment Department staff: