Tighe & Bond Provides Design for Long-Term, Durable Bridge
Tighe & Bond designed a new 14-foot bridge to replace a deteriorated cast iron pipe and stone box culvert that prevented fish passage. The new hydraulic system improved fish passage and habitat for herring and sea run brook trout. The road width at the stream crossing was widened from a single lane to two lanes, significantly improving traffic safety. Roadway drainage was also improved to mitigate suspended solids and nutrients from stormwater runoff.
Multiple stakeholders were involved with the planning process, including the Mashpee Wapanoag Tribe, abutters to the site, and funding agencies that included the Division of Ecological Restoration and the US Department of Agriculture Natural Resource Conservation Services.
Tighe & Bond’s design included a hydraulic and scour analysis, geotechnical evaluations, an alternatives analysis to evaluate various structure types, design drawings and specifications. State and local environmental permitting included a Massachusetts Department of Environmental Protection (MassDEP) Chapter 91 license, and obtaining Chapter 85 approval through the Massachusetts Department of Transportation (MassDOT). Technical assistance was provided during the bid phase and construction administration services with periodic on site observations.
The new bridge consists of a precast concrete frame on pedestal spread footings. The design involved a roadway closure, stream bypassing, and significant dewatering. The project was also located on the border of two adjacent towns, and coordination was needed between the two owners.
This structure provides a long-term durable bridge in compliance with MassDOT Chapter 85 requirements, stream crossing standards, and greatly improved fish passage.