Construction noise control for a major urban rapid transit line extension

The northwest extension of the Massachusetts Bay Transportation Authority Red Line Rapid Transit System involves the demolition and reconstruction of the current terminus station—Harvard Square Station, Cambridge—and the construction of three new stations, and associated subway tunnel and track work. This major construction program, scheduled to extend over a five year period, recognizes the potential noise impacts on the densely populated and highly developed communities in which the new construction is to take place. Cambridge, the most significantly affected community, currently has a noise ordinance limiting property line L10 and maximum A-weighted sound levels due to construction operations. The MBTA has incorporated the Cambridge limits into construction contract documents and has also included limits on noise produced by individual pieces of construction equipment. The construction noise specifications and implementation procedures are described along with the experience to date in actual contract applications. [This work is partially supported by the US Urban Mass Transit Administration and the Massachusetts Bay Transportation Authority.]