SILOAM SPRINGS, Ark. (KNWA/KFTA) — The U.S. Army Corps of Engineers is revealing why there’s been an increase in flooding along the Illinois River over the past couple decades.

The USACE Illinois River Flood Study took four years to complete.

One of the project managers is Jaysson Funkhouser. He said their calculations show rainfall totals have been about five to 20 inches above average each year, which has been creating higher water levels for more than 15 years and is the main reason for the flooding.

Another reason for the increase in flooding is Northwest Arkansas’ growth. Funkhouser said when a forest along the river is turned into a neighborhood, there’s often more flooding in that specific area, but has little effect on the rest of the river.

Along with flooding, Funkhouser said people are also losing land as it erodes into the Illinois River, and the sediment has the potential to change the quality of the water.

In the study, USACE tested possible ways to reduce flooding.

One solution is to add around 30 ponds to local farmland. Another is to add plants and trees to the banks of the river.

“Something that can hold the soil in place,” said Funkhouser. “The roots hold the soil in place, and it also slows the water down. The trees that create more friction for the water to flow through.”

Funkhouser said it’s outside the USACE to make these changes and will be up to those who own the land around the river instead.

Funkhouser encourages those impacted by the Illinois River flooding to look at how they can implement solutions found in the USACE study, or by attending a USACEC public meeting at the First Baptist Church in Siloam Springs on Tuesday, April 11 from 5:30 to 7:30 p.m.