CTRE is an Iowa State University center, administered by the Institute for Transportation.

Address: 2711 S. Loop Drive, Suite 4700, Ames, IA 50010-8664

Phone: 515-294-8103
FAX: 515-294-0467

Website: www.ctre.iastate.edu/

Iowa State University--Becoming the Best

Western Iowa Missouri River Flooding - Geo-Infrastructure Damage Assessment, Repair, and Mitigation Strategies

Pavement damage near I-680 and I-80 intersection

Eroded backfill beneath pavement on I-680

Pothole formed on gravel road due to eroded backfill under culvert

Complete breach of roadway embankment

Backfill erosion in bridge abutment approach


Principal investigators:

Co-principal investigators:

Project status


Start date: 10/11/11
End date: 09/27/13


Report: Western Iowa Missouri River Flooding: Geo-Infrastructure Damage Assessment, Repair, and Mitigation Strategies (17.91 mb pdf) September 2013

Tech transfer summary: Geo-Infrastructure Post-Flood Damage Assessment, Repair and Mitigation Strategies (3.32 mb pdf) Sep 2013



About the research


The 2011 Missouri River flooding caused significant damage to many geo-infrastructure systems including levees, bridge abutments/foundations, paved and unpaved roadways, culverts, and embankment slopes in western Iowa. The flooding resulted in closures of several interchanges along Interstate 29 and of more than 100 miles of secondary roads in western Iowa, causing severe inconvenience to residents and losses to local businesses. The main goals of this research project were to assist county and city engineers by deploying and using advanced technologies to rapidly assess the damage to geo-infrastructure and develop effective repair and mitigation strategies and solutions for use during future flood events in Iowa.

The research team visited selected sites in western Iowa to conduct field reconnaissance, in situ testing on bridge abutment backfills that were affected by floods, flooded and non-flooded secondary roadways, and culverts. In situ testing was conducted shortly after the flood waters receded, and several months after flooding to evaluate recovery and performance. Tests included falling weight deflectometer, dynamic cone penetrometer, three-dimensional (3D) laser scanning, ground penetrating radar, and hand auger soil sampling.

Field results indicated significant differences in roadway support characteristics between flooded and non-flooded areas. Support characteristics in some flooded areas recovered over time, while others did not. Voids were detected in culvert and bridge abutment backfill materials shortly after flooding and several months after flooding. A catalog of field assessment techniques and 20 potential repair/mitigation solutions are provided in this report. A flow chart relating the damages observed, assessment techniques, and potential repair/mitigation solutions is provided. These options are discussed for paved/unpaved roads, culverts, and bridge abutments, and are applicable for both primary and secondary roadways.