Bonnie Grissom was prepared for a vacuum cleaner.
That’s what builders of Washington Water Power Co.’s $66 million Rathdrum power plant told her she would hear when they fired up its turbines last month: A rumble like a vacuum cleaner being used in the next room.
But this particular carpet cleaner sounds like it holds 150 passengers and could fly round-trip to Seattle in under two hours, Grissom said.
“It sounds like a big jet is sitting outside your front door,” she complained.
Grissom and other neighbors on Singer and Boekel roads say the plant’s intermittent roaring rattles windows and doors. Some say they can no longer sleep without earplugs - even though they live a half-mile or more away.
WWP officials plan to fix the problem, but say they won’t likely find a solution until midsummer.
They also say the plant isn’t louder than they predicted. The noise is just a dramatic change for this once-quiet rural community.
“It can be sort of like Chinese water torture,” said James Reyff, a WWP consultant. “When there isn’t much else in the background, the sound is singled out.”
The controversial plant came online Jan. 2 and immediately began “throwing different sounds in different directions on different days,” said resident Jane Badraun. “Some days I can’t hear it at all.”
To some, it sounds like a train, to others, a plane.
“It’s been so bad some days we had to wear earplugs in bed - and that’s with the windows closed,” said resident Terri Martin.
It’s not loud enough to drown conversation, but residents worry the problem will be unbearable in the summer - when they open their windows.
WWP officials say they’re sympathetic, but noise control is complex.
The plant is emitting noises in nearby neighborhoods of up to 50 decibels, Reyff said. That’s no louder than a typical wooded area, he said.
“It has characteristics of an airplane, but not in their back yards,” he said.
Since Rathdrum-area residents are used to about 40 decibels, the change is significant.
Project manager Dana Zentz said developers merely underestimated the impact. “We failed to consider how appropriate the amount of change would be,” he said.
Weather also changes the noise level and makes it difficult to monitor, Zentz said. Temperature inversions trap the sound close to the ground and strong winds carry it far. That’s why residents only hear it on some days.
Additionally, the noise could be from several sources: An air-intake, a cooling module, the twin turbines’ exhaust systems.
Tracking down the source will tell WWP officials whether they need an air baffling system, a simple noise buffer or a much larger enclosure.
They’ve taken noise samples and are analyzing the data, but that could take all month, said Reyff. Then WWP must choose a solution and build it.
“That will probably take at least six months,” Zentz said.
The good news, he said, is the plant won’t operate often once spring sets in. Residents shouldn’t hear much during summer.
“We’re not trying to fight them,” he said. “We want to be good neighbors.”