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5. Pyrethroid TMDL BPA

Central Valley TMDL Projects
Pyrethroid Pesticides TMDL
and Basin Plan Amendment

On 8 June 2017, the Central Valley Water Board adopted Resolution R5-2017-0057, which adopted the Basin Plan Amendment (BPA) for the Control of Pyrethroid Pesticide Discharges and approved the supporting Substitute Environmental Documentation and Staff Report.

This BPA established measurable pyrethroid concentration goals and a program of implementation for the control of pyrethroid pesticides that are impacting or could potentially impact aquatic life uses in surface waters in the Sacramento and San Joaquin River watersheds of the Central Valley. It also established Total Maximum Daily Loads (TMDL) for waterbodies that are listed as impaired by pyrethroids on the Clean Water Act Section 303(d) list, and established provisions to address and/or prevent future pyrethroid listings.

Adoption and Approval Materials

• United States Environmental Protection Agency Action
  • USEPA Approval Letter - 22 April 2019
  • TMDL Checklist
• Office of Administrative Law Action
  • OAL's Notice of Approval, Endorsed Form 400, and Concise Summary (OAL File No. 2019-0107-03S)
• State Water Board Action
  • Final State Board Resolution (2018-0031)
  • State Water Board Meeting - 10 July 2018
    (Includes Agenda, Draft Resolution, Final Staff Report, Written Comments, and Response to Comments)
  • Notice of Opportunity to Comment, 3 October 2017
• Central Valley Regional Water Quality Control Board Action
  • Pyrethroids Method Development (Analytical Test Method Request and Laboratory Participation Questionnaire can be found under "Informal Workgroups")
  • Resolution R5-2017-0057 (includes final adopted Basin Plan Amendment language) - Adopted 8 June 2017
  • Final Staff Report (including CEQA Environmental Checklist and environmental analysis) - June 2017
  • Final Response to Comments
  • Agenda Package (including comments, summary sheet, resolution)
  • Late Revisions
  • Final Response to Peer Review Comments
  • Notice of Public Hearing

NEW - Pyrethroid Analytical Methods Validated for Compliance Monitoring

The Central Valley Water Board issued a request on 13 March 2019 that Environmental Laboratory Accreditation Program (ELAP) accredited laboratories develop performance-based analytical methods that can achieve the lower concentration goals required to assess compliance with the Pyrethroid BPA and TMDL. This is because the BPA sets low concentration goals for pyrethroids in discharge and receiving water, and therefore lower analytical reporting limits than commonly commercially available will be required for compliance monitoring.

The Central Valley Water Board has reviewed validation packages submitted in response to this request. As of 6 May 2020, the laboratories listed below have analytical methods that have been approved by the Central Valley Water Board for use in assessing compliance with the BPA. The appropriate contacts for each laboratory are included. This list will continue to be updated as additional laboratories have methods validated and approved by the Central Valley Water Board in the future.