Sterling Highway MP 58-79

DOWL completed environmental and design services for the $70 million Sterling Highway Milepost 58-79 Rehabilitation project that included new passing lanes and expanded shoulders to bring this 21-mile stretch of highway up to rural arterial standards. Wildlife enhancements were developed in response to a moose-vehicle collision analysis and include a new 140-foot single span bridge, five wildlife underpasses with structure spans ranging from 14 to 26 feet, and five miles of moose fencing with jump-outs (escape ramps). The design includes a pedestrian underpass to improve safety at the Skyline Trailhead, as well as bioengineering incorporated into revetment along the Kenai River to improve fish habitat. Retaining walls were incorporated to minimize impacts to Jean Lake and required rerouting of streams and drainage structures to avoid conflicts with the walls. Eighteen miles of the project corridor is located within the Kenai National Wildlife Refuge, requiring extensive coordination with the U.S. Fish and Wildlife Service.

Additional work included a hydrologic and hydraulic analysis, geotechnical investigation, traffic analysis, noise analysis, cultural resources survey, public involvement coordination, agency permitting assistance, and final design. DOWL also provided support for bidding and construction.