Somerville, Massachusetts is a city just northwest of Boston, one of the most densely populated in the country, and is bisected by several major highways. A 2019 Community Assessment of Freeway Exposure and Health (CAFEH) report focusing on the health impacts of highway proximity finds that most Interstate 93 (I-93) adjacent areas in Somerville are considered Environmental Justice communities. In 1973, the construction of the I-93 extension through Somerville demolished an existing neighborhood and greatly reduced nearby property values. Air pollution from on-road vehicles is a major contributor to smog and poor air quality, which have important negative impacts on human health and wellbeing.
More than 75,000 people are packed into Somerville’s 4.1 square miles, the most densely populated city in New England. Neighborhoods along the I-93 corridor are some of the most densely populated areas within Somerville, and are significantly more racially and ethnically diverse than Somerville as a whole: According to the CAFEH report, roughly half of the residents in neighborhoods next to I-93 are people of color, compared to the citywide average of 30 percent. Areas along I-93, particularly the south-facing side, are also less affluent and have a higher proportion of children compared to the rest of Somerville. For near-highway residents, the installation of noise barriers would reduce sound levels and exposure to traffic-related air pollution—ultimately improving life-long health outcomes through reduced risk of heart/respiratory disease, and improved mental health.
Despite substantial evidence of health benefits and equity implications of noise/pollution barriers, Massachusetts Department of Transportation (MassDOT) plans for noise barrier installations on state highways do not include I-93 in Somerville. MassDOT’s barriers are only considered for new highway construction where noise levels will exceed a threshold standard (Type I Projects) or areas that are on MassDOT’s Type II Priority List.
As a result of not being on MassDOT’s list of cities and towns most adversely affected by highway traffic noise, I-93 in Somerville does not meet the criteria for “Priority” sound barrier project. MassDOT only measures noise to determine if sound walls are needed—air pollution is not recognized as a valid basis for barrier installation. Currently, on the north-facing side of I-93 near the newly-developed Assembly Row, the Ten Hills neighborhood does have a sound barrier—while the south-facing side, comprised of portions of East Somerville, Winter Hill, and Somerville Housing Authority’s entire Mystic River Development, does not.
As Massachusetts continues to pursue their state climate and emissions goals while planning for equity and environmental justice, transportation reform must include changes that go beyond investments in electric and hydrogen fuel cell vehicles. For true equity, the transition to a carbon-free state must address legacies of infrastructure inequality and consider improvements that benefit not only travelers, but the communities they speed through as well.
