Type II Noise Barrier Program
The majority of noise barriers in New Hampshire and the rest of the United States have been constructed in association with substantial roadway improvement projects anticipated to result in highway traffic noise impacts which could be feasibly and reasonably mitigated with the installation of a noise barrier.
These substantial roadway improvement projects, known as Type I projects, typically involve the installation of a new roadway, the addition of through traffic lanes or substantial changes to the vertical or horizontal alignment of an existing roadway. Type I noise barriers are a form of environmental impact mitigation. As such, funding for Type I barriers comes from the Type I project resulting in the impact.
In 2016, the New Hampshire Department of Transportation (the Department) implemented a noise policy which contained procedural guidelines for the implementation of a Type II noise barrier program. The Type II noise barrier program would allow for the installation of noise barriers along some of the state’s most heavily traveled roadways to mitigate for existing noise impacts which are not associated with Type I roadway improvements. While the Department’s noise policy identifies the requirements which must be met for an area to qualify for a Type II noise barrier, to date, the Department does not have any funds available for the implementation of this program.
In 2017 the Department conducted a Statewide Type II Noise Barrier Screening Analysis to identify the benefits, length, location and approximate construction costs associated with the potential feasible and reasonable Type II noise barriers within New Hampshire. This planning study was intended to help identify the potential benefits and funding needs associated with the Type II program. The screening analysis evaluated noise levels at approximately 23,000 households within 1,500 feet of the state’s divided highways, and identified a total of 49 potentially eligible Type II noise barriers located within 20 different municipalities. If all 49 barriers were constructed to their full extent this would require a total of approximately 37 miles of barrier to be constructed at a cost of approximately $124.5 million.
Although the results of this planning study were helpful in identifying the potential needs associated with the Type II program, in order for a Type II noise barrier to ultimately be constructed there are numerous site specific requirements which must first be met, including several requirements placed on the local municipality. As such, this planning study should not be considered a final determination of eligibility, or lack thereof, at any of the evaluated locations. The specific requirements necessary for a location to be eligible for the construction of a Type II noise barrier can be found in the Department’s 2016 Noise Policy.