Water Quality Control Policy for Siting, Design, Operation and Maintenance of Onsite Wastewater Treatment Systems (OWTS Policy)

Summary of the Board Adopted Policy

Concise Summary of Regulatory Provisions

Title 23. Waters
Division 3. State Water Resources Control Board and Regional Water Quality Control Boards
Chapter 22. State Policy for Water Quality Control
Section 2924

On June 19, 2012, the State Water Resources Control Board (State Water Board) adopted Resolution No. 2012-0032, adopting the Water Quality Control Policy for Siting, Design, Operation, and Maintenance of Onsite Wastewater Treatment Systems (OWTS Policy). This Policy establishes a statewide, risk-based, tiered approach for the regulation and management of OWTS installations and replacements and sets the level of performance and protection expected from OWTS.

In accordance with Water Code section 13290 et seq., the OWTS Policy sets standards for onsite wastewater treatment systems (OWTS) that are constructed or replaced, that are subject to a major repair, that pool or discharge waste to the surface of the ground, and that have affected, or will affect, groundwater or surface water to a degree that makes it unfit for drinking water or other uses, or cause a health or other public nuisance condition. The OWTS Policy also includes minimum operating requirements for OWTS that may include siting, construction, and performance requirements; requirements for OWTS near certain waters listed as impaired under Section 303(d) of the Clean Water Act; requirements authorizing local agency implementation of the requirements; corrective action requirements; minimum monitoring requirements; exemption criteria; requirements for determining when an existing OWTS is subject to major repair, and a conditional waiver of waste discharge requirements.

The regional water quality control boards are required to incorporate the standards established in the OWTS Policy, or standards that are more protective of the environment and public health, into their water quality control plans within 12 months of the effective date of the OWTS Policy. Implementation of the OWTS Policy will be overseen by the State Water Board and the regional water quality control boards, and local agencies (e.g., county and city departments and independent districts) have the opportunity to implement local agency management programs if approved by the applicable regional water quality control board.