RAPID CITY, S.D. (AP) — The South Dakota Department of Transportation is creating more grip so your car won't slip on some of the Black Hill's windiest roads.

The process is called High Friction Surface Treatment, and the state DOT is the first in the nation to use it to reduce road-departure crashes on curvy roads in winter conditions.

Statistics show the new treatment is leading to less crashes, and it has earned the department some national recognition.

Andy Vandel, DOT's highway safety engineer, told the Rapid City Journal that the treatment is created by bonding an aggregate, made of calcined bauxite, to the roadway via an epoxy. Calcined bauxite is an alumina-based mineral that resists "polishing" better than standard road surfaces, according to Vandel. Polishing can cause a loss of traction, making the new material ideal for sharp corners where more traction is needed.

Vandel estimates the cost of each curve treated with this new material at roughly $150,000. He said the DOT has plans to add the material to other locations across the state in the coming years.

Last year, the state applied the treatment to 15 locations in the Black Hills, focusing on some of the highest-crash areas.

The 15 sites where the treatment was added averaged a total of 21 winter road condition crashes, including seven injury or fatal crashes per year for the five years prior to this project. Through one winter season, there was a total of one crash and zero injuries at these sites, according to the DOT's statistics.

"This project was the first demonstration in the country of how the technology of a high-friction surface treatment could be used to reduce road-departure crashes with winter road conditions as a contributing factor," state Secretary of Transportation Darin Bergquist said in a release. "Driver safety is a high priority for the department, and the innovative use of this treatment is already reducing crashes and saving lives."

Some of the areas that have the new highway treatment include tight curves on U.S. Highway 14A in Boulder Canyon and a stretch of Interstate 90 near Tilford. U.S. Highway 16 a mile west of the Keystone Wye Bridge and U.S. Highway 85 between Deadwood and Spearfish also received the new treatment.

The South Dakota Highway Patrol said they have noticed a decrease in crashes where the new treatment has been applied.

"As the South Dakota Highway Patrol continues its mission to reduce overall traffic crashes, I am proud to see the South Dakota Department of Transportation taking such proactive steps toward a similar mission," state Highway Patrol Capt. Jason Ketterling said in a letter support the DOT's application. "Without their research into new roadway materials and their application of them, it is reasonable to believe we would have seen similar crashes from years before."

Aside from reducing crashes, the DOT's new treatment has also been selected as a top-12 finalist in the 2018 America's Transportation Awards competition.

Sponsored by the American Association of State Highway and Transportation Officials, the project is a contender to be named best transportation project in the nation, as well as eligible to win a People's Choice award decided by online voting.

Seventy-nine projects were entered in the competition sponsored by AASHTO, AAA and the U.S. Chamber of Commerce. The Grand Prize (selected by a panel of experts) and People's Choice award winners will each receive $10,000 from AASHTO on behalf of the winning state's Department of Transportation for donation to a nonprofit charity or transportation-related scholarship of its choosing.

Online voting for the People's Choice award will continue through Sept. 22.

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Information from: Rapid City Journal, http://www.rapidcityjournal.com