San Diego Regional Water Quality Control Board Amends Regional MS4 Permit to Provide Alternate Compliance, Define Prior Lawful Approval of Development Projects, and Extend BMP Design Manual Deadline

On Wednesday, the San Diego Regional Water Quality Control Board approved amendments to its regional National Pollutant Discharge Elimination System ("NPDES") permit, Order No. R9-2013-0001, regulating discharges from large and medium municipal separate storm sewer systems (Phase I "MS4s") in the San Diego region. Originally adopted in 2013 for jurisdictions in San Diego County, the Regional Water Board is now adding jurisdictions in southwestern Riverside County which also must now comply with the permit's provisions (jurisdictions in southern Orange County were added earlier this year). Additionally, three important amendments to the MS4 permit were approved—an alternative pathway for achieving compliance with the permit's strict prohibitions and limitations, a definition of "prior lawful approval" for development projects able to proceed under prior regulations, and an extension of the deadline for each jurisdiction to implement a new or updated BMP Design Manual.

Permit now includes Alternate Compliance Pathway

First, the permit now includes an "Alternate Compliance Pathway," such that co-permittees who are willing to pursue significant measures to improve water quality will be deemed in compliance with the permit's discharge prohibitions, receiving water limitations and water-quality-based effluent limitations. Co-permittees who choose this optional means of compliance must implement Water Quality Improvements Plans that include certain interim and final numeric goals, water quality improvement strategies, and time schedules. The plans must also include, for each final numeric goal, annual milestones in five-year increments and dates for achievement of the milestones. The Alternate Compliance Pathway follows concerns raised by co-permittees that achieving compliance with the permit's numeric water quality prohibitions and limitations will take many years, and a strong recommendation from the State Water Resources Control Board that the regional boards consider such alternative compliance while water quality improvement plans are being implemented.

Definition of "prior lawful approval" provided

Second, the permit now includes a definition of "prior lawful approval," or when certain development projects may proceed under prior regulations. Co-permittees may now allow previous land development requirements to apply to a Priority Development Project if, prior to the effective date of the jurisdiction's new BMP Design Manual, the co-permittee has:

[a] Approved a design that incorporates the storm water drainage system for the Priority Development Project in its entirety, including all applicable structural pollutant treatment control and hydromodification management BMPs consistent with the previous applicable MS4 permit requirements; and

[b] Issued a private project approval, or functional equivalent for public projects, that authorizes the Priority Development Project applicant to commence construction activities based on a design that incorporates the storm water drainage system approval in conformance with Provision E.3.e.(1)(a)(i)[a]; and

[c] Confirmed that there have been construction activities on the Priority Development Project site within the 365 days prior to the effective date of the BMP Design Manual, or the Copermittee confirms that construction activities have commenced on the Priority Development Project site within the 180 days after the effective date of the BMP Design Manual, where construction activities are undertaken in reliance on the permit or approval, or functional equivalent for public projects, issued by the Copermittee in conformance with Provision E.3.e.(1)(a)(i)[b]; and

[d] Issued all subsequent private project permits or approvals, or functional equivalent for public projects, that are needed to implement the design initially approved in conformance with Provision E.3.e.(1)(a)(i)[a] within 5 years of the effective date of the BMP Design Manual. The storm water drainage system for the Priority Development Project in its entirety, including all applicable structural pollutant treatment control and hydromodification management BMPs must remain in substantial conformity with the design initially approved in conformance with Provision E.3.e.(1)(a)(i)[a].

Alternatively, the co-permittees may allow previous land development requirements to apply to a Priority Development Project if the co-permittee demonstrates that it lacks the land use authority or legal authority to require a Priority Development Project to implement the requirements of the new permit.

Implementation deadlines extended

Finally, the Regional Water Board extended the deadline for the co-permittees to implement a new or updated BMP Design Manual, the plan developed by the co-permittee to eliminate, reduce or mitigate the impacts of runoff from development projects (formerly known as the Standard Storm Water Mitigation Plan). Previously, the permit required each jurisdiction to implement a new or updated BMP Design Manual incorporating the permit's requirements by December 27, 2015. Now, given the amendments to the permit affecting development planning provisions, the deadline for the effective date of the BMP Design Manual is February 16, 2016, ninety days after approval of the amendments, unless otherwise directed by the Regional Water Board's executive officer.

If you have any questions about the Regional MS4 permit, please don't hesitate to contact us. We would be happy to assist you in evaluating your legal obligations under these new provisions.