I-5 Widening: Blakeslee Junction to Grand Mound NEPA Documentation
Location: Lewis County, Washington
DEA was the lead consultant on this $170 million project to widen I-5 from four to a minimum of six through-lanes from Mellen Street to Grand Mound. Work included reconstructing and realigning seven miles of I-5 including two interchanges, replacing two bridges at the Skookumchuck River and one bridge at Blakeslee Junction, widening I-5 from four to six lanes, seismic retrofitting the 216th Avenue bridge across I-5, constructing off-site stormwater mitigation, and updating onsite stormwater facilities and utilities along the route.
DEA prepared the environmental analysis, National Environmental Policy Act (NEPA) documentation, and archaeological studies, and participated in a value engineering study and a cost risk assessment. The DEA team developed 13 environmental discipline reports that included compliance with Section 106 of the National Historic Preservation Act and Section 7 of the Endangered Species Act. This work led to environmental compliance approval from the Federal Highway Administration as a Documented Categorical Exclusion (DCE). DEA also assisted the Washington State Department of Transportation with all federal, state, and local permitting.
WSDOT Excellence in Environmental Design Environmental Improvement Project Category, Southwest Region for Wetland Enhancement