In the next two years, Freeborn County’s roads will have another safety measure put in place.

The Freeborn County commissioners this week approved adding transverse rumble strips to all county state-aid highways and county roads that are blacktop or concrete and that have a posted speed of 55 mph. The strips will be put in place where vehicles approach stop signs.

Rumble strips are textured portions of road surface that create noise when a car passes over them, alerting drivers. Depending on placement, sometimes rumbles alert an approaching stop and sometimes they alert the edge of the roadway.

Freeborn County Engineer Sue Miller said there are about 128 different approaches — part of the roadways leading up to stop signs — that would apply in the county, and she hopes at least 70 of those could be completed this summer.

The cost of the total project is estimated at about $64,000.

Miller said the county is being divided in half with the roads south of Freeborn County Road 46 to be completed this summer, and the other half to be completed in 2013.

The action comes as people continue to debate the effectiveness of the strips. Studies, including ones in Minnesota and Iowa, have shown transverse rumbles don’t work for making motorists stop, though ones on the shoulders have been effective for keeping drivers from wandering off the pavement. For stopping, greater signage has proven more effective.

In 2005, the commissioners voted to phase out the rumble strips.

Commissioner Mike Lee, who has been pushing for the rumble strips since he ran for office in 2008, said he was pleased the measure was approved.

“I feel it’s another tool to help save lives on our rural roads,” Lee said. “I’ve lived out in the country, and they’ve worked for me. If we can save a life, that’s what I’m for.”

County board Chairman Dan Belshan said as a former milk truck driver he opposed the removal of the rumble strips back in 2005 because he was aware of them being a sensory safety device, especially on foggy and snowy mornings. He said he has wanted rumble strips put back as a safety measure for years.