Statewide Toxicity Provisions

The State Water Resources Control Board (State Water Board) is developing statewide numeric water quality objectives for both acute and chronic toxicity and a program of implementation to control toxicity, which are collectively known as the Toxicity Provisions. The Provisions would provide consistent protection of aquatic life beneficial uses in inland surface waters, enclosed bays, and estuaries throughout the state, and protect aquatic habitats and life from the effects of known and unknown toxicants.
This project also includes the establishment of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California.

ANNOUNCEMENT! The First Revised Draft Toxicity Provisions and First Revised Draft Staff Report are now available. A workshop will take place on November 15, 2019 in Rancho Cordova, CA to discuss: 1) the development of a new Appendix section in the draft Staff Report summarizing recent data and publications, 2) the intent and the development of a study to determine sources of laboratory variability when using the C. dubia chronic toxicity reproduction test , and 3) the details of an option to delay inclusion of the median monthly effluent limitation using the C. dubia chronic toxicity reproduction tests in permits that do not already have numeric effluent limitations until a future date.


Project Timeline

Dates are tentative and subject to change.

October 19 to
December 21, 2018
July 25, 2019 August 2019 October 3, 2019 November 15, 2019 Late Fall, 2019 Winter 2020
Public Comment Period Release of Revised Provisions Staff Public Workshops Board Workshop Staff Public Workshop Release of Responses to Comments State Water Board Consideration

2019 First Revised Draft Toxicity Provisions Documents

2018 Draft Toxicity Provisions Documents


2012 Draft Toxicity Policy

In 2012, the State Water Board released a draft Policy for Toxicity Assessment and Control for public comment.

External Peer Review

The following journal articles are referenced in the TST peer review synopsis.


Test of Significant Toxicity (TST)

TST Test Drive

  • Raw Data from the Final Whole Effluent Toxicity Test Drive Analysis of the TST is now available. In response to stakeholder requests, the State Water Board is publishing the raw data used for the 2011 TST Test Drive Analysis. These datasets aggregate the replicate and test endpoint values for each individual test, as well as the intermediate and final calculations for the statistics used in the analysis.

    The Appendix A files are data from tests of effluent from individual dischargers, as summarized in Appendix A in the Test Drive Analysis. The data are separated into individual files that compile the data for specific type of tests. The Appendix B file is the entire dataset of ambient data used in Appendix B of the Test Drive Analysis.
    • Appendix A
      • Acute Mysid Survival Test Data
      • Acute Daphnid Survival Test Data
      • All Fish Species Acute Survival Test Data
      • Chronic Ceriodaphnia dubia Reproduction and Survival Test Data
      • Chronic Fathead Minnow Growth and Survival and Reproduction Test Data
      • Chronic Macrocystis pyrifera (Giant kelp) Growth and Germination Test Data
      • Chronic Mysid Growth, Survival and Fecundity Test Data
      • Chronic Mytilis edulis (Blue Mussel) Development and Survival Test Data
      • Chronic Haliotis rufescens (Red Abalone) Development Test Data
      • Chronic Selanstrum (Green Alga) Growth Test Data
      • Chronic Atherinops affinis (Topsmelt) Growth and Survival Test Data
      • Chronic S. purpuratus (Purple Sea Urchin) Fertilization Test Data
    • Appendix B
  • Appendix A and Appendix B data from the Final Whole Effluent Toxicity Test Drive Analysis of the TST in Microsoft Excel format
  • Final Whole Effluent Toxicity Test Drive Analysis of the TST - updated December 2011

  • 2010 Draft Policy for Toxicity Assessment and Control and 2011 Workshops

      2011 Staff Workshop Presentations:

    2006 Public Scoping Meeting

    Get updates by email regarding the draft Policy for Toxicity Assessment and Control, subscribe online to the “Freshwater Plans and Policies” mailing list.