Blaine County commissioners agreed on Tuesday not to support a noise-mitigation wall along state Highway 75 south of St. Luke's Wood River Medical Center.
"A wall in the scenic corridor is antithetical to every part of Blaine County Code," said commission Chair Larry Schoen.
The proposed wall, 8 feet high and 610 feet long, was recommended by the Idaho Transportation Department as a way to block excess noise from the potentially expanded highway to the Cold Springs Mobile Home Park just south of the Broadway Run intersection.
Though the wall would be within the state right-of-way and out of the county's jurisdiction, any wall in this area over 4 feet high is a violation of the county's Scenic Overlay District ordinance.
"You should think of such a wall as a giant horizontal tombstone [marking the death of the Scenic Overlay ordinance]," said former County Commissioner Len Harlig.
The mobile-home park and the berm in front of it are both non-conforming, only allowed by the county because their construction predates the ordinance. Opponents of the wall brought up the park's non-compliance as part of their arguments.
Steve Cook, representative of the Ketchum Planning and Zoning Commission, said the impact to drivers outweighs the needs of park residents, especially as the noise level in the park is only a decibel over what ITD considers to be a reasonable level.
"For one decibel, are we going to protect a non-conforming use?" Cook asked.
Residents of the park said the wall is necessary to preserve their quality of life. The problem is that drivers at the Broadway Run intersection go from a standing stop to 55 miles an hour in a very short distance, said park resident Richard Frasier.
"Everybody's hard on the gas, and that's why there's so much noise at that corner," he said. "You cannot even hear yourself think."
Tracy Olsen, project manager for national design firm WHPacific, said that the wall would reduce the noise level in the trailer park by 10 decibels at the east side of the park and by six at the west.
The expansion plan includes noise mitigation through a lowered speed limit and a shift of the road away from the park. Olsen said the level of noise within the park would remain roughly the same, even without the wall.
The commissioners expressed sympathy with the landowners and suggested other noise-mitigation options.
"From my perspective, a combination of a berm or a wood fence that was landscaped appropriately seems like an acceptable solution," Schoen said in a later interview.
However, Olsen said that for a berm to provide the necessary mitigation, it would have to be the same size as the proposed wall.
"It would still have to be an 8-foot tall berm," she said.
Regardless of whether a berm is feasible, the commissioners stated that a wall would have economic and visual impacts that outweigh the park residents' desire for a decrease in traffic volume.
The plan for the proposed wall will now be returned to the Federal Highways Administration, which will evaluate whether to consider the commissioners' collective opinion over the wishes of property owners and residents of the park.
Katherine Wutz: firstname.lastname@example.org