Water Quality Objectives Update Amendment

Approved Amendment

The revised water quality objectives have been approved by Office of Administrative Law and are now in effect under state law. To comply with the Federal Clean Water Act (CWA), and before the surface water objectives become fully effective under the CWA, they must first be approved by the Unites State Environmental Protection Agency (U.S. EPA).  


The Water Quality Objective (WQO) Update Amendment to the Water Quality Control Plan for the North Coast Region (Basin Plan) has been developed by staff of the North Coast Regional Water Quality Control Board (Regional Water Board). The amendment includes a number of actions relative to updating water quality objectives for both surface waters and groundwaters in the North Coast Region. This amendment was previously part of the "Groundwater and Surface Water Protection Amendment," which was divided into the WQO Update Amendment (Phase I) and the Amendment to Update Regional Groundwater Protection Policy (Phase II) as it was too large to undertake as one Amendment.

The primary goals of the WQO Update Amendment are to: 1) make clear and transparent the process that staff uses when translating narrative water quality objectives into numeric values protective of beneficial uses, particularly with respect to chemical constituents; and 2) amend the Basin Plan’s water quality objectives to support the protection of human health and aquatic ecosystems. To accomplish these goals staff proposes that:

  1. The objectives for chemical constituents for surface water and groundwater be updated to reflect current scientific understanding and to more clearly apply to the protection of all beneficial uses;
  2. A toxicity objective for groundwater be articulated, using the toxicity objective for surface water as a model for the explicit protection of human health;
  3. The DO objectives be revised to: a) better protect sensitive aquatic organisms from depressed DO; b) better ensure that the natural pattern and range of DO variation is maintained in those waterbodies unable to meet the aquatic life-based objectives due to natural conditions; and c) reduce the possibility that natural variation in DO is erroneously identified as DO impairment leading to improper 303(d) listings; and
  4. Language be added to Section 3 to clarify how numeric values can be identified to implement narrative water quality objectives in accordance with the specific circumstances of a project and the specific controlling statute and regulations.
For detailed information on the proposed changes including proposed Basin Plan language, please refer to the Staff Report below.

Available Documents

June 18, 2015 Materials as Adopted

The following documents were adopted by the Regional Water Board during the June 18, 2015 hearing.  Minor changes to the documents were made during the hearing and have been incorporated in the versions present below.

Final Staff Report

Staff Report for the proposed Water Quality Objectives Update Amendment, June 18, 2015.  Individual Sections of the Staff Report are available for ease of downloading:

Mailing List

We encourage users interested in the Water Quality Objectives Update Amendment and other basin planning issues to subscribe the Basin Planning email list .

If you would like to be added to the hard-copy mailing list, please contact Jeremiah Puget at 707-576-2835 or 5550 Skylane Blvd, Suite A, Santa Rosa, California, 95448.

Contact Us

For information, comments, or questions concerning the WQO Update Amendment:

Jeremiah Puget

  (Page last updated 8/24/23)