DES MOINES, Iowa — The Iowa Department of Transportation is taking steps to lower fatal car crashes in the state by making changes to roadways, and recent data is showing improvements.

State Safety Planner, Larry Grant, listed four key initiatives officials are taking to curb severe crashes.

Rumble Strips

The first is adding center line and edge line rumble strips to every two-lane rural highway. These alert drivers if they veer away from their lane.

Grant said the DOT started adding shoulder and center line rumble strips on resurfacing projects for the past 15 years, but a special focus started in 2024. 1,900 miles of center line rumble strips were constructed through five special projects since then.

Now, roughly 90 percent of the DOT rural two-lane highway miles have rumble strips, compared to about 56 percent in summer 2024.

Studies have proven that using rumble strips in rural highways reduced all crashes by up to 20 percent.

Widening Pavement Markings

The DOT is also widening paint strips on roads from four inches to six inches. This makes the lines more visible for drivers and adds more space between lanes. It also helps cars with new technology detect lane separations more easily.

Grant said this project started on the interstate in November 2019 and should be completed by 2026.

Widening pavement markings on all primary roads beyond the interstate started in 2022.

Grant said wider edge line markings on rural roadways can reduce crashes by around 10 percent, and some sources indicate it can reduce fatal and injury crashes by almost 40 percent.

Installing Roundabouts

Roundabouts lower vehicle speed, thus making crashes less likely to be severe.

Grant said there are 170 roundabouts statewide with roughly 10 to 15 added per year. There are currently 21 roundabouts on the DOT’s primary highway system, and 16 more are in construction or design.

Cable Median Barriers

Cable median barrier installations started in 2002, but were emphasized in 2010. Grant said there are now over 330 miles of it on divided roadways with high volumes of traffic and narrow grass medians.

Grant referenced a study from Iowa State University that found interstate cable median barriers save eight lives per year in Iowa.

“The last factor is the driver,” said Grant. “And if the driver is not willing to pay attention to what they’re doing driving that 3,000-pound vehicle or more, that is a recipe for disaster.”

According to the Iowa Department of Transportation, there have been 186 fatal car crashes statewide in 2025 as of September 5th. This statistic is lower than this time in previous years. Since 2020, there has been a steady decline in fatal accidents.