West Hill Drainage Study
January, 1999

The West Hill Drainage Study provides information about drainage basin hydrology, drainage system capacity, and potential impacts of stormwater to identify needed improvements in the area's stormwater system. The study was undertaken to respond to a large number of drainage complaints King County received from throughout the area.

The West Hill study area covers unincorporated areas of King County that are currently surrounded by Seattle to the north, Renton to the south and east, and Tukwila to the south and west. Sections of this area are often referred to as West Hill, Skyway, Bryn Mawr, Earlington, Lakeridge, Campbell Hill, and Panorama View.

The goals of the study were to:

1. Compile existing drainage data to inform land use decisions and guide recommendations for capital improvements in the area's drainage infrastructure.
2. Compile existing drainage data to inform decisions related to water quality planning as required by King County's National Pollution Discharge Elimination System permit.
3. Provide a single reference for drainage information that serves the best interests of the area's residents, through current use by King County and private developers, and for the eventual transfer to the newly annexed or incorporated cities.

The West Hill Drainage Study text and figures are provided here in version 3 of Adobe Acrobat. For help with Acrobat, please see our Acrobat Help Page. Study maps are provided as separate files to reduce file sizes and speed up file downloads.

West Hill Drainage Study (273 Kb)

• West Hill Drainage Summary Map (2.99 Mb)
• Hydrologic Summary Map - 25 Year Flow (1.58 Mb)
• Proposed Capital Improvement Projects Map (1.48 Mb)
• Sewer Service Area (636 Kb)
• Water Features (736 Kb)
• Surficial Geology (690 Kb)
• Zoning (817 Kb)
• Concurrent CIP List (90 Kb)
• West Hill Basins - Peak Flow Values, KCRTS (42 Kb)