Iowa’s new road signs use lasers to detect icy roads, suggest on-the-fly speed limits

Lasers pointed at the pavement can detect the road’s condition. The data is then passed along to a sign that suggests an appropriate speed.Lasers pointed at the pavement can detect the road’s condition. The data is then passed along to a sign that suggests an appropriate speed.

The Iowa Department of Transportation believes it has found a new way to help save lives during days when weather conditions aren’t ideal for driving.

The new signs will display an “advised speed limit” based on special sensors that use lasers to monitor winter pavement conditions, according to KCCI News.

“We’re detecting the amount of ice or snow and slush on the road, kind of doing some math in the background and coming up with a number and a condition,” Iowa DOT engineer Willy Sorenson told KCCI.

Sorenson and company are installing special software that calculates a safer speed. The software will then send information to four digital speed limit signs along Interstate 35, where the technology will first be tested.

Instead of the posted 65 mph speed limit, the new suggested limit may be 55 mph during icy days.

“This is really the first in the nation where a DOT is recommending a speed and a reason why you should be going that speed,” Sorenson told KCCI News.

The $200,000 project is currently in a testing phase. Iowa DOT hopes to have it ready to go next winter.