Vail tests freeway noise
VAIL – On Tuesday morning, with microphone-looking devices thrust out toward Interstate 70, a bunch of people in Vail appeared to be interviewing the freeway. In a sense, they were.The devices were decibel-readers, intended to rate the volume of noise created by passing trucks, cars and motorcycles. The readings showed that many vehicles, including cars, offended the town’s law for noise.But more revealing was what offended the ears of council members assembled along I-70 in front of the Vail Post Office. What they found most annoying were those vehicles that caused the meters to jump to more than 90 decibels. And what those vehicles all had in common was an absence of mufflers. And they were not just 18-wheel trucks.For council members, several conclusions were drawn. Diana Donovan, who argues against heavy-handed treatment of large trucks, heard evidence to reinforce her viewpoint. “It’s not a jake-brake issue,” she said. “It’s a muffler issue.”Such comments sit well with the trucking industry. The issue was of such importance to Jacobs Vehicle Systems that the company recalled an employee out of retirement in Seattle and flew him to Colorado for a three-minute appearance before the council. The company manufactures the most commonly used device, called a “jake brake,” for using a truck’s engine compression to slow the vehicle.The town’s noise ordinance, which is somewhat tougher than regulations from the U.S Environmental Protection Agency, allows a maximum of 80 decibels from cars and 90 decibels from trucks as measured 25 feet from a vehicle. Along the highway, that is measured from the borrow pit.
At Tuesday’s noise test, a small diesel pickup truck (classified as a car for these purposes) measured 85 decibels, while an SUV was 84, both in violation of the law. Without cars, conversation registered at around 66 decibels, and one pause in conversation among the council members left the needle at 60.It would appear any Harley-Davidson would break the law. A Harley without a muffler, as most owners of that particular brand of motorcycle prefer, caused 93 decibels. A Harley with the muffler that comes installed by the company, registered 81 decibels. Still later, a smaller motorcycle passed at only 74 decibels, the quietest vehicle of the session.In general, the only cars, SUVs and small trucks that stayed within the law were those that were smaller and going the speed limit of 65 or less. Most of the larger trucks stayed within the increased limit for trucks.But what was obviously breaking the limit were trucks without mufflers. A test truck, going the speed limit but without a muffler on its jake brake, measured 103.5 decibels. A large truck grinding its way up on the opposite side of the highway registered 96.6. But a truck going the speed limit with a muffler was at only 87 decibels, little more conspicuous than a SUV.Even a smaller truck, one from the town of Vail fleet, showed how much difference a muffler can make. The smaller truck going 75 mph with a muffler measured 92.5 decibels. Slower and muffled, it was 87.
Clearly, mufflers are the story. That makes enforcement – or education – the issue. Existing laws require mufflers. Colorado became the first state last year to require mufflers on jake brakes and other engine-compression devices. Greg Fulton, director of the Colorado Motor Carriers Association, a trade organization for regional truckers, said Colorado hopes to see other states adopt similar laws, to make enforcement easier. But even within Colorado, inspectors at the ports of entry are looking for mufflers, and fining trucks without them. However, the result is less than full compliance.As well, other laws require mufflers of motorcycles, cars and trucks. However, police in most jurisdictions do not bother to enforce muffler laws, and the fines are little more than parking meter violations of $15 to $25.
As a result of Tuesday’s demonstration, the Vail council wants more study of the spikes in noise, and seems less concerned about the steady din from the freeway. Council members also want to better understand how tires can make a difference, particularly studded tires used during winter. The town’s current approach is to enforce the speed limit of 65 as a way to hold down the roar. It does not directly enforce the noise law.However, the town’s noise consultant, Michael Hankard, says that depending upon tires and surface of the highway, the noise from a passing vehicles increases only one or two decibels for very 5 mph in increased speed. Tires alone are unlikely to cause the noise to rise above 90 decibels. Another approach is suggested by Jim Lamont, executive director of the Vail Village Homeowners Association. Vail, as well as other jurisdictions, has portable display units that inform passing vehicles the speed limit, as well as how fast their cars are going. A similar apparatus should be assembled for noise, he says.Vail, Colorado