• Some building and utilities permits issued by the City of Bellevue require a storm drainage report to be submitted for plan review. Prepare your report using the requirements outlined in the 2017 Surface Water Engineering Standards (SWES), Section D2 - D6. For assistance in submitting your report online, refer to Electronic Plan Requirements and Electronic Review Efficiency. For questions regarding your submittal, contact the Utilities Review desk.

    • All plan sheets must be a minimum of 18 x 24 inches. 
    • Storm drainage reports must be on 8 ½ x 11 inches and should be separate from the geotechnical report.

    Project Information

    • Project address
    • Name, address and stamp of preparer (if a licensed individual)
    • Vicinity map

    Report Requirements

    • Table of contents.
    • Utility standards and Department of Ecology codes pertinent to the project.
    • Project overview - existing and proposed conditions.
    • One quarter mile downstream analysis.
    • Off-site capacity analysis (if applicable).
    • Site Assessment and Planning Packet
    • Pre-developed and post-developed chart showing square footage of hard surfaces and pervious surfaces.
    • Figure 1.4 or 1.5 highlighting the flow path used to determine stormwater minimum requirements for the project.
    • Highlight flow path on 2017 SWES, Figure 5.1, for infiltration feasibility.
    • Details of infiltration testing, if required (test hole must be a minimum of six feet deep per 2017 SWES Appendix D-10).
    • Discussion of how each minimum requirement is being met.
    • Thorough discussion of List #1, List #2 or LID performance standard (2017 SWES D104.2(e)). Include infeasibility criteria per 2017 SWES Table D-9.1 and D-9.2.
    • Sizing calculations for Best Management Practices (BMPs) proposed.
    • When required per 2017 SWES D4-03, provide hydrologic/hydraulic calculation methodologies, inputs, assumptions and results for analysis of off-site conveyance capacity.