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Central Valley Pyrethroid Control Program

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

This Control Program established pyrethroid numeric triggers and a conditional prohibition of discharge of pyrethroids to protect aquatic life uses (WARM/COLD) in surface waters in the Sacramento and San Joaquin River watersheds. It also established Total Maximum Daily Loads (TMDLs) for nine urban waterbodies listed as impaired by pyrethroids on the Clean Water Act Section 303(d) list.

Adoption and Approval Materials

• United States Environmental Protection Agency Action
  • USEPA Approval Letter - 22 April 2019
• 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)
• Central Valley Regional Water Quality Control Board Action
  • Pyrethroids Method Development
  • 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

NEW - Draft Pyrethroid Research Plan

During the development of Resolution R5-2017-0057, Regional Board staff recognized that the data used to evaluate the potential for registered pyrethroid products to cause or contribute to water quality concerns contained considerable knowledge gaps. Therefore, Resolution R5-2017-0057 was drafted to include a provision that the Regional Board will work with stakeholders to develop a Pyrethroid Research Plan that will describe research and other special studies to inform future iterations of this control program (e.g., potential objectives, program refinement).

For more information regarding the Pyrethroid Research Plan, please see the Pyrethroid Research Plan webpage.

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.