Mountrail getting ready to rumble
Rumble stripes will be added to highways in Mountrail CountyBy ELOISE OGDEN Regional Editor eogden@minotdailynews.com
Fact Box
More to know about rumble stripes
BISMARCK Rumble stripes are grooved into the surface of the roadway so they are actually below the surface, said Billie Jo Lorius, communication specialist for the North Dakota Department of Transportation in Bismarck.
"Center line rumble stripes are similar to rumble strips used on the right side of the road, with an added feature in which a reflective material is painted on top of the center line stripes," she said.
She said each groove measures 7-inches long (parallel to running length of road) and 1-foot wide (perpendicular to running length of road. The depth will be one-eighth inch to one-half inch.
"Center line rumble stripes are being implemented to improve safety on our two-lane highways," Lorius said. "They have been used in other states and found to be effective in reducing head-on crashes and opposite direction sideswipe crashes."
Rumbling sound
She said the stripes provide a rumbling sound and a physical vibration to alert drivers that they are leaving the driving lane. In addition to the sound and vibration benefits offered by the center line rumble stripes, research has found that they are easier to see in rainy weather because there is greater reflectivity on the vertical side of the groove.
Other states have used rumble stripes and they have proved to be an effective safety feature, Lorius said.
She said in 2003, the Insurance Institute for Highway Safety conducted a study that analyzed 210 miles of treated roads in seven states before and after the installation of center line rumble stripes.
"The results indicated a 15 percent reduction for all injury crashes, as well as a 25 percent reduction in head-on and opposing-direction sideswipe injury crashes," Lorius said.
Rather new in N.D.
She said in North Dakota, rumble stripes are relatively new. She said the first ones were implemented last summer on N.D. Highway 1806 beginning at Fort Lincoln State Park south of Mandan, continuing south to the junctions of N.D. Highways 24 and 6 near Cannon Ball.
She said the rumble stripes have been effective in reducing the number of "run off the road" accidents.
STANLEY Drivers will get a wake-up call if they hit rumble stripes that will be installed this year on a section of N.D. Highway 23 from New Town to Plaza and also from the intersection of N.D. Highways 23 and 8 to U.S. Highway 2 at Stanley.
Scott Zainhofsky, planning and programming engineer for the North Dakota Department of Transportation in Bismarck, said the work was bid in July. The work should be implemented this construction season.
The rumble stripes will notify drivers when they are leaving their lane. "They go right on the center line and sides," Zainhofsky said.
Adding rumble stripes to the center line and edge of the highways was one of the suggestions the Transportation Department officials made to Mountrail County commissioners to make the roads safer in these areas.
Last August, the council commissioners asked the Transportation Department to reduce the speed from 65 mph to 55 mph on Highway 23 from Parshall to New Town, and from the junction of Highway 23 and N.D. Highway 8 to Stanley, as well as other safety measures because of the heavy truck traffic and recent fatalities. These areas are in the heavy oil-traffic areas.
Transportation Department studied the areas last year and recommended, in a letter sent to commissioners early this year, several changes to be made, which would be programmed and constructed as soon as practical.
Zainhofsky said the study showed that speed changes were not recommended. "I understand the desire to lower speed limits," Zainhofsky said. But he said the traveling public doesn't obey lowered speed limits.
In the letter to Mountrail commissioners, Francis Ziegler, Transportation Department director, explained to commissioners these are areas where the national and state standard call for speed limits to be set according to prevailing traffic speeds.
In the specific areas noted by commissioners, the prevailing speed was found in the Transportation Department study to be slightly greater than the existing 65 mph speed limit, Ziegler said in the letter.
Zainhofsky said the rumble stripes are done to alleviate lane departures in both directions.
He said the work to install rumble stripes doesn't take long once the contract is awarded. He said he fully anticipates the work will be done this year.
Zainhofsky said the study also recommended right-turn lanes at Highways 23 and 8 and N.D. 23 and N.D. 37. The Highways 23 and 37 intersection is just north of Parshall and N.D. 23 and 8 intersection is several miles east of New Town.
"That won't happen until next year," he said.
The Transportation Department also recommended increasing the radius of the northeast quadrant of the Plaza intersection N.D. 23 and 64th Avenue Northwest intersection) to improve the turning conditions for large trucks.
The intersection projects are scheduled to be bid in May 2010, Transportation Department officials said.
As for four-laning these roads, Zainhofsky said, "The traffic there does not justify four laning."
"They were really looking for widening shoulders and lowering the speed limit," Zainhofsky said. Commissioners asked to have the shoulders widened on Highway 8.
But in reference to widening the shoulders on Highway 8, Zainhofsky said widening the shoulders doesn't help with head-on crashes and it's very expensive to do.
"The rumble stripes on the edge line and center line help both head-on and run-off road crashes and (we) can install them for a fraction of the cost," Zainhofsky said.
