San Diego Region - Clean Water Act Section 305(b) Surface Water Quality Assessment and Section 303(d) List of Water Quality Limited Segments

The federal Clean Water Act (CWA) requires States to assess waterbodies (Section 305(b)), as well as identify and make a list of those surface water bodies that are polluted (Section 303(d)). These water bodies, referred to in law as "water quality limited segments," do not meet water quality standards even after discharges of wastes from point sources have been treated by the minimum required levels of pollution control technology. Wastewater treatment plants, a city's storm drain system, or a boat yard are a few examples of point sources that discharge wastes to surface waters. States are required to compile these water bodies into a list, referred to as the "Clean Water Act Section 303(d) List of Water Quality Limited Segments" (List). States must also prioritize the water bodies on the list and develop Total Maximum Daily Loads (TMDLs) to improve the water quality. States are allowed to report on all their assessed waterbodies under section 305(b) and those listed as impaired in a single integrated report.

The "Water Quality Control Policy for Developing California's Clean Water Act Section 303(d) List" is the policy for the State and Regional Water Boards to follow when developing updates to the List. This policy describes the process by which the State and Regional Water Boards comply with the requirements of the Clean Water Act in developing the List.

2018 "Off-cycle" Water Quality Assessment 305(b) Update: Public Meeting and Opportunity to Comment

The San Diego Water Board is proposing updates to the CWA 305(b) Report as a result of "off-cycle" assessments of readily-available biological data.

Public Meeting: 9:00 a.m. Wednesday, February 12, 2020

2014 Water Quality Assessment and 303(d) List Update

State Board approved the 2014 303(d) List on October 3, 2017, by Resolution No. 2017-0059, and on April 6, 2018, USEPA approved the List. The below documents are available upon request.

  • Regional Board Approved Integrated Report for the San Diego Region
    • Resolution No. R9-2016-0196
    • 2014 Integrated Report Staff Report (updated October 12, 2016)
      • Appendix A: Proposed Updates to the 303(d) List
      • Appendix B: Category 5 Waterbody Segments
      • Appendix C: Category 4a Waterbody Segments
      • Appendix D: Category 4b Waterbody Segments
      • Appendix E: Category 4c Waterbody Segments
      • Appendix F: Category 3 Waterbody Segments
      • Appendix G: Category 2 Waterbody Segments
      • Appendix H: Category 1 Waterbody Segments
      • Appendix I: Fact Sheets and Interactive Map
      • Appendix J: Miscellaneous Changes
      • Appendix K: Administrative Record

Approved 2008-2010 303(d) List

The San Diego Water Board adopted the 2008 Clean Water Act Sections 305(b) and 303(d) Integrated Report on Evaluation of Surface Water Quality and Listing of Impaired Water Body Segments for the San Diego Region (2008 Integrated Report) on December 16, 2009. The final 2008 Integrated Report was incorporated into the statewide 2010 Integrated Report that was approved by the State Water Board on August 4, 2010. On November 12, 2010, USEPA approved the 2008-2010 CWA Section 303(d) List that includes listings for the San Diego Region. More information , including the 2010 Integrated Report and interactive map of all assessed waters in California, can be found on the State Water Board webpage. The below documents are available upon request.

Clean Water Act Sections 305(b) and 303(d) 2008 Integrated Report for the San Diego Region

  • FINAL: Clean Water Act Sections 305(b) and 303(d) 2008 Integrated Report for the San Diego Region (2-09-10)
    • Appendix A - New and Revised Decisions (pdf)
    • Appendix B - Summary of All Decisions for All Waterbodies (pdf)
    • Appendix C - Category 2 Water Body Segments
    • Appendix D - Category 3 Water Body Segments
    • Appendix E - Category 4A Water Body Segments
    • Appendix F - Category 4B Water Body Segments
    • Appendix G - Category 4C Water Body Segments
    • Appendix H - Category 5 Water Body Segments
    • Appendix I - Fact Sheets
    • Appendix J - Miscellaneous Changes
    • Appendix K - References
    • Appendix L - Response to Public Comments (pdf)

Approved 2006 List of Water Quality Limited Segments

On June 28, 2007 the U.S. Environmental Protection Agency gave final approval to California's 2006 Section 303(d) List of Water Quality Limited Segments.

The documents below provide information on the 2006 List for the San Diego Region and are available upon request..

  • 2006 Table of Water Quality Limited Segments for the San Diego Region
  • 2006 Fact Sheets Supporting Recommendations for Listing, Delisting, and Area Changes for the San Diego Region.

Other Links

  • USEPA has a web page which provides information on current activities associated with the Section 303(d) listing and Section 305(b) assessment processes. The Consolidated Assessment and Listing Methodology (CALM) initiative is currently being developed and addresses identification of impaired waters under Section 303(d) and preparation of water quality assessment reports under Section 305(b) of the Clean Water Act.
  • USEPA Region IX's web page includes information on monitoring, assessment (including List updates), and TMDL programs for Arizona, California, Hawaii, Nevada, the Pacific Islands subject to U.S. law, and approximately 140 Tribal Nations.