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King County Washington home

Archived Surface Water Design Manuals

Links to outdated stormwater documents archived for future reference for cases where they are referenced in municipal codes.

Older (inactive) versions of the Surface Water Design Manual (SWDM)

Related Topics

Flood services

Services for residents to manage and reduce river flooding.

Groundwater

Groundwater data, maps, reports, and other resources.

Watersheds, rivers, streams & lakes

Find water and land related resources and services by drainage area.