Public Comment Period -- Draft Modification of the Phase I Municipal Stormwater General Permit

Please clarify whether Pierce County's requirement to first evaluate the three preferred BMPs when Enhanced Treatment is required is included in Ecology's equivalency determination and whether a Phase II jurisdiction adopting the Pierce County progra...↓m would also be expected to adopt this BMP-selection hierarchy. If so, Ecology may wish to identify this requirement in the special considerations for Pierce County, particularly because the Fact Sheet emphasizes that BMP-selection criteria are integral components of an approved equivalent program.

King County's 2026 program adds 6PPD-Q/URMS as a downstream water-quality problem requiring special attention while also stating that there are currently no Ecology- or King County-approved/designated water-quality treatment facilities for URMS/6PPD-Q treatment. Please clarify how Ecology evaluated this provision for functional equivalency and whether it creates any specific BMP-selection or mitigation obligations for jurisdictions adopting King County's approved program.

Draft Appendix 10, Part 3.B states that the City of Seattle achieves equivalency with Ecology's "2026 Stormwater Management Manual for Western Washington." We believe this should reference the 2024 Stormwater Management Manual for Western Washington, consistent with the applicable permit cycle and the references used for the other Phase I jurisdictions. Please revise accordingly.↓