After years of planning, debate and local opposition, only one block of a 20-foot-high noise wall is being built in Apple Valley along Cedar Avenue as it is widened for rapid bus transit.

The noise wall pitted businesses and city and county officials against the Federal Highway Administration (FHA). The feds have a major say because they are contributing $23.4 million toward the $55.8 million Cedar Avenue upgrade, which runs from 138th Street south to 215th Street in Lakeville, Dakota County Engineer Mark Krebsbach said.

"I don't think that a suburban community should have to have a noise wall," said County Commissioner Will Branning, of Apple Valley. "In a suburban setting, you don't want a precedent for closing off and making a tunnel through your community."

Branning said the County Board, Apple Valley officials and business leaders jointly opposed the walls.

The 376-foot wall stands south of 153rd Street and protects townhouses, which are across Cedar from a Cub Foods and a parking lot. FHA rules required a survey of townhouse residents. With only about 10 residents voting, the wall was approved by a one-vote margin, Branning said.

"To get the federal money we had to put [the wall] up," he said.

The noise barrier costs $124,000, Krebsbach said.

"We fought heavily against it," said Ed Kearney, president of the Apple Valley Chamber of Commerce. He said chamber leaders met with city officials early on.

"We all agreed, no matter how it shakes out, to do everything to keep the city united," Kearney recalled. "A noise wall would have divided the city. Cedar Avenue already does, but walls would do that even more."

Minnesota has 112 miles of noise walls that cost an average of $2.1 million a mile to build, said Peter Wasko, a noise-control supervisor for the state Department of Transportation (MnDOT). He said state standards are stricter, requiring residential noise levels near a road project to be 65 decibels or less, compared with 70 decibels under federal standards. State rules require noise walls to cut residential noise by at least 5 decibels, he said. For comparison, he said a 10-decibel reduction would cut noise in half.

Wasko said businesses often oppose noise walls because they impair business visibility to potential customers driving past.

The busway expansion is the first project in which the county had to deal with a noise wall, Krebsbach said. The county is usually exempted from noise mitigation rules unless federal money is involved, he noted. The rules require noise modeling to estimate how much the widened road would increase noise levels in nearby residential areas.

Krebsbach said one potential wall section in Lakeville was dropped early because of an unfavorable cost-benefit analysis.

Local opposition barely stopped a third, 720-foot-long segment north of 160th Street. City leaders cited expensive engineering challenges and a change of heart by a few residents whose votes created an anti-wall majority among homeowners who would sit in the wall's shadow on the west side of Cedar.

City Administrator Tom Lawler questioned the benefit of the block-long wall that was favored by the townhouse residents.

"Our sense is that where you have long interstate highway miles, noise walls are beneficial," he said. "But in small segments along Cedar Avenue, you wonder if that is beneficial to those behind them."

Sheila Kauppi, MnDOT's south area engineer, said residents, including those behind noise barriers being built along Interstate 35W in Burnsville, are usually happy to get the tall walls.

Daron van Helden, president of the Burnsville Chamber of Commerce, said the only business he knew of that complained about the freeway wall was the LivInn Hotel, whose sign could no longer be seen from I-35W. He said after talking to City Council members, they granted the hotel a variance to increase its sign size and height so it is visible over the noise barrier.

Compared with other states, Minnesota ranked seventh for miles of noise walls at the end of 2007, when the last FHA survey was done. The state was right behind New York, with 109 miles. California was tops with 491 miles. The survey said the nation then had a total of 2,506 miles of noise walls.

Jim Adams • 952-707-9996

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