Project Summary

US Route 1 is a MaineDOT Priority 1 Corridor. This 2.75-mile section starting in Keegan Village heading north was “unbuilt,” meaning it had not been engineered and just evolved over the years, causing this section to lack modern safety standards: no paved shoulders, lacking superelevation, steep roadside slopes without guardrail, poorly delineated or missing sidewalks, and no ADA ramps. The structural box was insufficient causing rutting and longitudinal cracking requiring MaineDOT to construct a pavement treatment every three to five years. There were also drainage issues created by abutting property owners, and habitat connectivity and hydraulic concerns with several cross culverts. Existing conditions were evaluated for horizontal and vertical geometry, roadside design (guardrail), roadway structural box, closed and open drainage systems, sidewalk, and ADA to determine the improvements that could be made while remaining within the available construction budget.

To remedy the deficiencies, 8’ paved shoulders were added in Keegan Village to accommodate on-street parking while 4’ paved shoulders were added outside the village, superelevation was added to the curves requiring it, roadside slopes were flattened to eliminate guardrail, and curbing/sidewalks were added within Keegan Village and extended to the nearby housing development including crosswalks and ADA ramps. Reconstructed approximately 0.75 miles of the structural box and raised the roadway profile 1’ for the other 2 miles to make use of the existing structural box materials, minimizing cost. The closed drainage system in the village and 17 cross culverts were replaced – five precast box culverts while two others added energy dissipators. Project successes: Safety improvements for all, sidewalks for pedestrians, paved shoulders and pavement ride quality for vehicles, improved drainage for the environment, and habitat connectivity for animals.