Bothell Downtown Revitalization/Transportation Improvements
Arnie Sugar (HWA GeoSciences Inc.)
Don Ranger; Steve Morikawa, Terrie Battuello, (City of Bothell)
Lucy Auster (King County)
Dan Hansen (Perteet Inc.)
Presented at the Brownfields and Land Revitalization Conference
Tacoma, Washington, October 2008
Abstract
The City of Bothell is in the preliminary design phase of two major transportation improvement projects, the Bothell Crossroads and the SR 527 Multiway Boulevard. These are part of an overall Downtown Revitalization Plan, which includes multiple projects and planning initiatives aimed at transforming Bothell into a more vibrant, sustainable and thriving community.
The transportation projects include:
- Realignment of an inefficient intersection of two major roadways (SR 522 and SR 527), and
- Creation of a multiway boulevard, the first of its type in the region, with a combination of central arterial and turn lanes, bordered by tree-lined local access and parking lanes.
The project will impact multiple contaminated properties, and affords a unique opportunity to perform an integrated area-wide cleanup on soil, ground water and surface water, including several multiple-property ground water plumes. The City is implementing a comprehensive assessment of potentially contaminated properties, including free technical assistance from the King County Solid Waste Division's Brownfields Program. The assessment so far has identified several sites impacted by petroleum hydrocarbons, metals and chlorinated solvents. Chlorinated solvent impacts to several properties have been attributed to potential off-site sources, which may include three former dry cleaner sites. In addition to the known contaminated sites, releases of petroleum and solvents from the Horse Creek outfall into the Sammamish River have been occurring for many years. Efforts to locate the source have been unsuccessful due to site access issues, complex site hydrogeology and potential underground utility migration pathways. Soil and ground water remediations will be conducted as part of transportation improvements, to protect human health and environmental resources, as well as allow redevelopment of remaining land not needed for rights-of-way.