Puyallup, WA Environmental Rules: Stormwater Management (2026)

10 PMC, the city's stormwater management regulations, applies to all development, redevelopment, and construction site activity within the incorporated area of Puyallup. 040 the city formally adopts the Washington State Department of Ecology's Stormwater Management Manual for Western Washington, including its thresholds, minimum requirements, and variance criteria, as the operative standard citywide. 050 requires developers to comply with that manual and employ best management practices to control stormwater flows, provide treatment, and control erosion and sedimentation, and requires an off-site analysis with mitigation measures for any project that discharges stormwater beyond its own property.

Runoff must be discharged at its natural location so it is not diverted onto, or away from, adjacent downstream property, and a project may not produce a significant adverse impact on the downhill parcel. Private stormwater drainage facilities remain the responsibility of the property owner, who must record maintenance performed and file an annual report with the public works department by January 30th each year, retaining those records for at least three years. The city, in turn, maintains public stormwater facilities located in easements and rights-of-way once they are formally accepted.

300 separately bans any cross-connection between a stormwater drainage system and a sanitary sewer system, treating an existing cross-connection as a nuisance subject to immediate abatement, with the city able to abate it and bill the owner if the owner fails to act after notice.