Stormwater and New/Redevelopment

The Development Engineering Division reviews development applications that involve land development or proposed subdivisions to ensure they meet city and state regulations, including impacts to stormwater. The city ensures that permitted projects meet city design standards, codes, and state laws. See the city’s Development Engineering page for more information.

Development and Technical Standards

The cities stormwater code can be found in SVMC Title 22: Design and Development Standards.

Design standards must also comply with the Spokane Regional Stormwater Manual (SRSM), which provides technical guidance in the design, operation , and maintenance to control the quantity of stormwater runoff from the development projects in Spokane Valley. This local drainage manual is equivalent to the Stormwater Management Manual for Eastern Washington (SWMMEW) and is updated with every municipal stormwater permit issuance. The city is currently working with Spokane County on updating the SRSM to meet the new requirements in the 2024-2029 Eastern Washington Phase II Municipal Stormwater Permit which became effective August 1, 2024.

Low Impact Development (LID)

LID is described as a stormwater and land-use management strategy that aims to replicate pre-disturbance hydrologic processes through techniques like infiltration, filtration, storage, evaporation, and transpiration. The most common LID Best Management Practices (BMPs) are bioretention cells, Bioinfiltration swales, and natural dispersion.

More information can be found in Appendix 3-d of the SWMMEW.