Sewer Permits FAQs

Frequently Asked Questions: Sewer Permits & Construction

For detailed technical requirements, please refer to the Delta Diablo (District) Sewer Permits page to access its Standard Specifications and Drawings. Note that the District uses the same Standard Specifications as the Central Contra Costa Sanitary District (Central San).

General Policies & Ownership

What is the basic sewer service policy for my property?
Each property with a separate Assessor's Parcel Number (APN) must have a public sewer extended to it. The only exception is the final lot in a service line, which may be served by a private side sewer via a recorded easement.

Who is responsible for maintaining the sewer line?
Maintenance responsibility depends on your location:

  • Antioch & Pittsburg: The property owner maintains the house/building sewer up to the property line.
  • Bay Point: The property owner maintains the entire side sewer from the building to the public sewer main, including the connection tap or wye.
The image illustrates a sewer system layout, showing connections from a house to the main sewer line, including lateral and building sewers.

Are sewer lateral certifications required when selling a home?
No. The District does not require sewer lateral certifications for property sales. Condition assessments are the responsibility of the homeowner.

How do I apply for a sewer permit?
You can apply in two ways:

  1. Online: Use the Citizen Self-Service System (user guide available online).
  2. Email: Download the Residential or Non-Residential application and send it to permits@deltadiablo.org.

What are the payment options?
The District only accepts checks. Please include your application number and deliver via:

  • Drop-off: Monday–Friday, 8:00 am – 5:00 pm (see map on the Permits page).
  • Mail: Delta Diablo, Attn: Treatment Plant Admin, 2500 Pittsburg-Antioch Highway, Antioch, CA 94509.

Where can I find the current fee schedule?
The fee schedule is located on the Sewer Permits page of our website.

What are the standard pipe size and material requirements?

  • Size: Minimum 4" for single-family homes; minimum 6" for multi-family or commercial.
  • Materials: PVC (SDR-26 is typical), ABS, Ductile Iron (DI), or HDPE.

What are the slope and depth requirements?

  • Slope: Minimum 2% (1/4" per foot); maximum 150% (18" per foot).
  • Cover: Minimum 18" of cover is required within two feet of the building foundation. For other areas, refer to Central San Standard Specifications Section 4-08.

Do I need an inspection?
Yes. All sewer installations must be air-tested for joint tightness in the presence of a District Inspector. You must schedule this with the inspector listed on your permit.

How do I handle a residential repair?

  • Antioch/Pittsburg: Contact the City directly for repair permits.
  • Bay Point: Submit plans and applications to the District. If using pipe bursting, include the Special Approval Form.

What is required for commercial projects?
Submit plans detailing the total square footage and previous use of the building.

  • Car Washes/Laundromats: Must include specific calculations for estimated daily wastewater discharge and machine specifications.
  • Grease Interceptors: Must have a minimum volume of 1,000 gallons (see DWG 23-02).

How do I renew an Industrial Discharge Permit?
Contact the Pretreatment group at ecstaff@deltadiablo.org  or (925) 568-2307.