Eagan will get its first traffic noise barrier this spring, according to city and state officials.
Construction on 1,500-foot concrete and wood wall—located along the west side of Interstate 35E north of Diffley Road—will begin on April 2, Minnesota Department of Transportation Noise Abatement/Air Quality Supervisor Peter Wasko said. The wall, which is expected to cost just over $520,000, will likely be complete by June, Wasko said. The average wall height will be 15 feet.
Legislation passed in 1996, Wasko said, requires MnDOT to develop a statewide ranking system to address noise issues in areas throughout the state that exceeded the state's daytime noise standards. The rankings, last updated in 2011, included the site along I-35E near Diffley Road. The department earmarks $2 million annual for noise walls, Wasko added, which allows the construction of two or three barriers per year.
City and MnDOT officials met with neighborhood residents in 2009 at a public hearing for the project, Wasko said. MnDOT will cover $475,000 of the project's cost, while Eagan will contribute $47,124. Construction of the sound wall is not expected to impact traffic or lead to any lane closures on I-35E, Wasko said.
Noise levels along the freeway in Eagan range between 68.5 and 75.5 decibels, according to City Engineer Russ Matthys, who cited test data collected by MnDOT at 2030 Vienna Ln. The noise level at another test site—4388 Cinnamon Ridge—measured 74.5 decibels, Matthys said.
Conversational speech registers 60 decibels, according to information posted by MnDOT. In order for MnDOT to consider construction of a noise barrier, the wall must attain at least a five-decibel reduction in noise.
Matthys doesn't think it's unusual that a city the size of Eagan is just now getting its first noise barrier along a busy thoroughfare.
Homes in the young community are generally newer and are better insulated from sound than older areas, he said. Eagan also has wider margins along I-35E that may mitigate some of the noise from the freeway, Matthys added. Traffic noise complaints, once relatively common, are now few and far between, he said.
While this noise barrier may be the first of its kind in the city, it won't likely be the last. MnDOT is planning to construct two other noise walls along I-35E in Eagan, including one north of Deerwood Dr. in 2016 and one near Kettle Park in 2017.