A new safety measure implemented along several rural highways in St. Louis and Lake counties is creating a bit more of a rumble than county officials may have intended.

Residents along county roadways that have been modified with what are known as “rumble stripes” are complaining loudly that the continuous stripes of gouged pavement have changed their normally quiet, rural neighborhoods into irritating and noisy places.

“The noise was instant,” stated Gary and Roberta Skogman, of rural Tower, in a recent letter to the editor of the Timberjay. “Before the rumble stripe gouging machine was out of sight, we knew our lives would never be the same,” wrote the Skogmans, who live along County Road 77, near Lake Vermilion.

The Skogmans are not alone. County officials acknowledge that the installation of the stripes on about 81 miles of county roadway earlier this year has generated plenty of criticism. “My first call was from my brother and he didn’t mince words,” said County Commissioner Mike Forsman.

Vic Lund, acting traffic engineer for St. Louis County, said he’s had about 60 phone conversations with residents, most of whom were upset by the stripes.

Residents along the affected highways say the location of the stripes, directly along the white fog line, has greatly increased the frequency of noisy impacts. The problem is particularly troublesome along curves, since drivers often stray outside of the white line on sharper curves. That’s one of the problems for the Skogmans, since their home is located near a highly-traveled S-curve on County Road 77. “Anyone with a boat trailer, they’re going to hit it all the time,” said Gary Skogman. “On the curves, it seems every third or fourth car hits it,” he added. “It’s like a plane taking off when they they do.”

Lund argues that the noise complaints are based more on perception than reality. He said a MnDOT noise study found that the decibel reading from a car hitting the stripes was equivalent to that of a truck on the highway. Still, Lund acknowledges that the higher frequency of the sound emanating from the rumble stripes may appear louder to human ears than the lower frequency of more typical traffic sounds. “It appears to our ears that it’s louder, even though it isn’t really,” he said. “I’m not discounting that they hear the noise. But the claim that this noise is worse than other traffic sounds is proven false. I’ve got the data to prove it.”

More striping ahead

If the stripes have raised objections this year, the complaints are likely to intensify next year. That’s because the second phase of the program is set to get underway in 2011, when the county plans to stripe another 113 miles of rural highway. The $1 million program is funded at 90 percent through the Federal Highway Safety Improvement Program, while St. Louis and Lake counties are contributing the remaining local match. A similar program will allow the county to stripe many more miles, eventually affecting about 280-300 miles of rural county highway.

County public works officials defend the stripes, citing federal studies that show they reduce the number and severity of “run-off-the-road,” or ROTR, accidents caused by inattentive, drowsy, or even intoxicated drivers. County officials estimate the stripes could reduce the number of ROTR accidents by 20-30 percent, which they believe provides a good return on investment.

Still, most studies on the effectiveness of rumble stripes have been conducted in freeway situations. County officials acknowledge that no official studies have explored how well they work on rural two-lane highways, and that estimates of crash reductions are based on studies from other types of roads.

Lund argues that the safety push is coming from both the state and national level and that it is a worthwhile response to critics who have complained for years that the county wasn’t doing enough to improve highway safety. “It really comes down to, on a monthly basis, I would get a phone call from someone asking when is the county going to do something about all these deaths. Now we are doing something.” In 2008, notes Lund, drivers on the 3,000-3,500 miles of county roads experienced a total of 13 fatal or major injury accidents.

Safety versus serenity

For Skogman and other rural county residents, it’s a quality of life issue. Skogman agrees that the stripes do have value for motorists, but he questions whether those benefits are offset for county residents by the increased noise.

“If they moved the stripes a foot to the outside, it would reduce the noise by 50-75 percent,” he said. In fact, according to the Federal Highway Administration, most states do exactly that, in order to reduce noise complaints.

Lund said moving the stripes outside of the white line might reduce noise, but would fail to achieve one of the other benefits of the stripes— improved visibility of the fog line in wet weather, particularly at night. Skogman agrees that the lines are more visible in the rain, but he questions if an incremental improvement is worth the impact to otherwise quiet neighborhoods.

Lund challenges the notion that anyone’s quality of life is impacted. “It’s a perceived impact, not a real impact,” he said.

Lund agrees that the costs and benefits must be balanced, but he said county traffic officials are coming down on the side of safety. “It is our value set that it is more important to improve safety than worry about noise,” he said.

The value set of county residents never came up in the decision. County officials never held any public meetings to ask residents how they might balance the competing values.

Despite the high number of complaints, Lund said county officials have no intention of amending their striping program.

Are the stripes always beneficial?

While traffic safety officials agree that the rumble stripes reduce the number of ROTR accidents, the value of the stripes does vary. According to the Federal Highway Administration, rumble stripes are most effective when installed on roadways with relatively wide shoulders, that give drivers the chance to recover once the stripes have alerted them to potential danger.

While most of the county roads included in the latest striping program do have relatively wide (6-8 foot) shoulders, not all of them do— and that could limit the usefulness of the stripes. “Rumble strips installed…with no useable recovery area beyond the shoulder are of questionable value,” states the FHA in a 2001 technical advisory on rumble striping.

Lund notes that the federal recommendations are merely guidance, not a requirement. “We’ve made the decision to install with paved shoulders, ranging from 2-to 8 feet,” he said.