Drakes Island Bridge, Wells, Maine
The Drakes Island Bridge provides sole access to the Drakes Island community over a tidal crossing in the northern marsh area of Wells Harbor. The bridge has timber deck and abutments that show signs of deterioration with areas of timber rot, damage, section loss and marine bore holes. Additionally, the guardrail has sections in complete failure. The bridge is surrounded by a tidal marsh and abutted by privately-owned parcels.
GZA GeoEnvironmental, Inc. (GZA) will complete investigations of subsurface conditions at the bridge and along the roadway approaches. This information will be utilized to determine the recommended substructure type for the proposed bridge.
CMA Engineers will perform a comprehensive review of alternative approaches to the project design, utilizing information collected through survey, geotechnical explorations, environmental coordination, H&H, and input from the Town. Alternatives will focus on bridge replacement options, construction methods, environmental impacts, and coastal access during construction.
Tidal Crossings
US Rt. 1A, Ocean Boulevard Crossing, Rye, NH
Squamscott Road Tidal Crossings, Stratham, NH
The Nature Conservancy, in conjunction with the NHDOT, is in the planning phase of
replacing 3 tidal culverts. A 42 inch span concrete deck supported on dry laid granite block
abutments on Route 1A between Locke Road and Harbor Road in Rye, NH and two 18 inch
reinforced concrete pipe structures on Squamscott Road between Route 108 and Chisholm
Farm Drive in Stratham, NH.
Nute Road Bridge, Madbury NH
In 2012, CMA Engineers assisted the Town of Madbury with the design of emergency interim repairs to NHDOT Bridge No. 056/072 which carries Nute Road over the Bellamy River. CMA Engineers worked closely with NHDOT Bureau of Planning and Community Assistance on behalf of the Town after the structure was closed and barricaded following a NHDOT bridge inspection identified significant deterioration of the plate arch structure.
In 2018, the Town contracted CMA Engineers to conduct an engineering study for the replacement of the culvert with funding through the NHDOT State Bridge Aid Program. Through the engineering study, it was determined that the existing culvert should be replaced with a 33-foot single span bridge that included precast concrete beams supported on abutments with spread footings. The bridge cross section included 2 travel lanes and was designed for HL-93 live loads. In 2020, CMA Engineers completed final design, plans and specifications and construction was completed in 2021.
