Seattle’s Urban Watersheds
Seattle has four major receiving waters: Lake Washington, the Ship Canal and Lake Union, the Duwamish River and Puget Sound. Three urban basins, or watersheds, contribute to each of these receiving waters. These watersheds represent discrete areas that contribute to Seattle's receiving waters through stormwater drainage and combined sewer overflows (CSOs).
- Duwamish Basin
- East Waterway Basin
- West Waterway Basin
- North Lake Washington Basin
- Central Lake Washington Basin
- South Lake Washington Basin
- North Puget Sound Basin
- Central Puget Sound Basin
- South Puget Sound Basin
- North Lake Union Basin
- South Lake Union Basin
- Ship Canal Basin