InTrans / Feb 06, 2026
Soy-based pavement technology replaces, renews 24 miles of rural Iowa roadways
A train of heavy equipment slowly worked its way across 8.6 miles of a northeast Iowa county road last summer.
The corn growing along C14 just south of West Union was dark green and high. Farmhouses and outbuildings were on the horizon. The ditches along the roadway were freshly mowed. It was a good day to fix a rural road built in the 1960s, patched up and covered over ever since, now deteriorated and even crumbling beneath the surface.
The fix was soy pavement technology developed by Iowa State University engineers.
The repairs to C14 were part of a full-scale, 24-mile demonstration of “soy roads”—which used 12,000 to 15,000 bushels of soybeans and eliminated the need for 40,000 barrels of crude oil—in rural areas of Fayette and Clayton counties and the town of Volga.
Four different road projects used soybean-based paving products developed by Iowa State engineers Eric Cochran, the Mary Jane Skogen Hagenson and Randy L. Hagenson Professor in Chemical and Biological Engineering, Christopher Williams, the Gerald and Audrey Olson Professor in Civil Engineering, and their research groups including Williams’ Asphalt Materials and Pavements Program (AMPP). The technology is now produced by their startup company, SoyLei Innovative Products.
The $7 million project was funded in part by federal Community Project Funding but ultimately became a public-private partnership.
“They put their trust in Iowa State to deliver,” Williams said. “And I think we delivered a great product.”
Read more about the project from a recent Iowa State University News Service article, as well as a previous AMPP news story about the research.