Freeway Neighbors Worried About Noise

There are plans in the works to make significant improvements to I-405, including some major widening action. Of course, while freeway improvements are good, it's pretty much impossible for any kind of progress to happen anymore without some group protesting the change. For this project, it is nearby homeowners concerned about noise .

Residents who live along Interstate 405 already know how loud traffic noise can be as they barbecue on their decks and patios.

Now, some homeowners in south Bellevue neighborhoods are worried about how much worse it could get once planned widening projects move the freeway even closer to their backyards.

In addition to noise walls, the traditional way to dampen the freeway din, they want state Department of Transportation officials to consider a less-tested way to mitigate noise: rubberized asphalt.
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Officials say surveys of noise at dozens of sites on I-405, and computer modeling that predicts future levels, show most locations will not experience levels that push them above the state's limit of 66 decibels.

If the noise is louder than that, mitigation measures such as noise walls must be considered. At 67 decibels, two people having a conversation, standing five feet apart, would have to raise their voices to hear each other.

Though residents have expressed concerns about other issues, such as drainage, environmental impacts and freeway alignment, the potential for increased freeway noise tops the list, said Goran Sparrman, director of Bellevue's transportation department.
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In the case of the rubberized asphalt on 104th Street [in Bellevue], it began to deteriorate after just a few years.

"Our experience is that it works well for a couple of years," Sparrman said.

"But the problem for us is it doesn't wear like normal and it comes out in chunks."

I can understand not wanting more noise, but I don't really see what the big deal is here. The state has clear rules about noise levels and mitigation methods, and those rules are being followed already. Did these people buy their homes next to the freeway expecting the noise level to decrease? Why are they trying to push an inferior and expensive solution to a non-existent problem?

(David A. Grant, King County Journal, 05.30.2006)