Salt Lake County, UT Environmental Rules: Stormwater Management (2026)

§17.22.050 applies its performance criteria to all sites by default. The only exits are a waiver or a determination by the county engineer that the site is exempt, so an applicant cannot simply decide the criteria do not apply. Under subsection (B)(1), the design of any storm drain system within the boundaries of, or discharging into, a county storm drain system must be supervised by a Utah registered professional engineer and must carry that engineer's seal. A design without a licensed engineer's seal cannot be approved for anything that touches county drainage infrastructure.

Under subsection (B)(2), systems must control peak flow rates and reduce post-construction runoff back toward preconstruction levels, using pervious areas and infiltration where practical, with the county's adopted BMP manuals supplying the accepted design methods. Sites near sensitive resources such as cold-water fisheries or water supply reservoirs face added performance criteria beyond that baseline. The ordinance also directs applicants to consult the county engineer on design requirements before or during site design, not after plans are drawn, and subsection (C) bars runoff from one lot exceeding pre-existing rates onto a neighboring lot.