Officials head to Benton County to investigate windmill noise concerns

As debate continues in Tippecanoe County over windmill regulations, a pair of county building commission officials went to see -- and hear -- windmills for themselves this week.

Building Commissioner Ron Highland and Ken Brown, deputy building commissioner, visited Benton County on Tuesday to learn more about wind turbine developments and take sound measurements.

Amendments being considered for Tippecanoe County's wind energy ordinance would make the building department a key player in monitoring and regulating windmill developments here.

When standing almost directly underneath one of Benton County's 200-foot towers Tuesday, Highland said the decibel machine measured as high as 67 decibels. To put that in perspective, 67 decibels measures somewhere between the noise level of conversational speech and the sounds of a business office.

Another measurement taken about 800 feet from the turbine showed a 50-decibel sound level. And that wasn't at the full 1,000-foot distance that turbines would have to be built away from homes and businesses, Highland said.

"I didn't find it to be an obnoxious noise at all," he said, "The only thing you could really hear was this wispy noise. You could hear the flaps every once in a while and the rotors going."

But Highland said the sound readings will vary from day to day, especially given changing weather conditions. During the winter, for example, Highland said sound will travel further across snow and through thinner air.

Noise concerns are being raised most commonly by residents, Highland said. It's one of the issues resident Terry Leffew mentioned at the commissioners' March 15 meeting.

But Leffew, who lives in southern Tippecanoe County, said he is also worried about safety, his property value and other side effects.

Sally Slavens, Benton County's building inspector, took Highland and Brown on the tour Tuesday. She had them take sound readings from her property, which is surrounded by commercial windmills.

"We can hear the wind going through the blades, but we're used to it now. Honestly, our air conditioner at home is louder than the wind whooshing through those blades," Slavens said.

Benton County was home to Indiana's first wind farm, which meant officials there didn't have nearby communities with which to compare notes. Slavens said officials traveled to Iowa and Illinois to learn from other areas before adopting an ordinance.

"But our ordinance, we have upgraded it along the way as we learned things," she said.

Some changes have been as simple as wording. For example, Slavens said, the ordinance originally required setbacks from occupied residences, but it was changed to read "occupied structures" to include schools, churches and other structures.