Highway department looking at noise reduction along parts of I-49

FAYETTEVILLE -- The Arkansas Department of Transportation wants to hear from the public about traffic noise from widening and interchange construction projects along Interstate 49 in Washington and Benton counties.

Steve Lawrence, engineer for District 9, which includes Benton County, said the department's Environmental Division has been working on a noise study for a couple of years. The study identified at least four areas where sound walls could be built.

"Since we started widening I-49, taking it to six lanes, I've had a fair number of calls about noise, and we've been referring people to our Environmental Division," Lawrence said. "There have been some that asked quite a few times about it, as far as wanting to know more about it and what the results were going to be."

The study analyzed noise levels at 18 areas along I-49 and will help to determine whether sound walls are needed and, if so, where they should be built. The study was delivered as two reports, one for Washington County and one for Benton County.

Final decisions will be made after talking to residents and property owners who stand to benefit. Lawrence said the Transportation Department encourages the public to be involved even for those areas studied but not named as potential sites.

"That's the main thing we want. We want people to come and give us their feedback, what they think," he said. "It's all part of the process, and it can change what we do. It has, especially on construction jobs. We get feedback from the public and go back and look at things again and it changes our opinion."

The department is making the draft traffic noise reports available for public review online in preparation for at least one virtual meeting in late January, according to Don Nichols of the department's Environmental Division.

"Residents and property owners along the corridor should review the studies and participate in the ArDOT meeting that will be scheduled in early 2021," said Tim Conklin, assistant director at the Northwest Arkansas Regional Planning Commission.

The overall corridor includes 26 miles of interstate between Martin Luther King Jr. Boulevard in Fayetteville and Arkansas 72 in Bentonville.

One report specifically addresses the noise analysis within Benton County from the Washington County line to Arkansas 72. A separate report documents the noise analysis within Washington County from Martin Luther King Jr. Boulevard to the Benton County line.

Sound walls were determined to be the only available potential abatement measure. Sound walls are the most common technique used for roadway projects.

Sound walls are solid obstructions built between the highway and homes along a highway. They do not completely block noise, according to the Federal Highway Administration. Effective noise barriers typically reduce noise levels by 5 to 10 decibels, cutting the loudness of traffic noise by as much as half.

Federal Highway Administration noise regulations require that noise abatement be evaluated first for "feasibility" and, if feasible, for "reasonableness."

"The effect of having a sound wall built has to impact enough people to make it cost-worthy," Lawrence explained. "It basically takes an apartment complex or a real concentrated housing addition for there to be enough people there to recognize benefit from a sound wall. And, also, the noise level has to be a certain amount before it can even be considered."

The state's allowable cost for building a sound barrier is $36,000 per benefited residence. In most of the areas studied, the cost/benefit ratio was too high for the number of residences that would benefit.

In Benton County, six areas with possible noise-sensitive land uses, called noise analysis areas, were identified in the study. One, west of I-49 between South 28th Place and South Bellview Road, is considered feasible and reasonable. An estimated cost is more than $2 million.

Building sound walls at the remaining Benton County locations was determined to likely be too expensive and not help enough people, according to the study.