Evaluation of alternative highway noise abatement strategies for one community

For the Massachusetts Department of Transportation (MassDOT), HMMH undertook an investigation of the potential benefits of several noise abatement options for a community of single-family homes located along I-90. This investigation was prompted by noise complaints and was not associated with a roadway improvement (Type I) project or barrier retrofit (Type II) project. MassDOT scoped HMMH to evaluate many options that could potentially reduce existing traffic noise levels to below the applicable FHWA Noise Abatement Criteria (NAC) of 66 dBA, Leq in the loudest hour of the day. The strategies included a vegetative buffer, safety barrier, privacy fence, earth berm, and noise barrier along the highway and along the residential property line. The paper details the analysis approaches taken and results of each strategy. The variable terrain throughout the study area presented challenges to achieving the goal with any of the individual strategies, but a combination of the two noise barrier placements was predicted to be successful.