Flood Mitigation

Flood Protection in Coralville

Since 2008, the City of Coralville has made significant improvements and investments to protect low-lying areas from floodwaters on Biscuit Creek, Clear Creek, and the Iowa River. 

Flood Levels

All flood protection improvements built since 2008 were designed to protect to one foot above the 2008 water levels.


Funding for these projects included City funds, a $27.1 million I-JOBS I grant, $13 million in Community Development Block Grants, $9.7 million in state sales tax increment funding, $7.2 million in U.S. Economic Development Administration funds, $1.8 million in HUD National Disaster Resilience Funding, $450,000 in Federal Emergency Management Agency alternate project funds, and a $3.6 million I-JOBS II grant.
Permanent & removable floodwalls along the Iowa River

Flood Mitigation Projects

Residential and commercial areas that flooded in 2008 have subsequently been protected through the following work:
  • Reconstructed and raised the 1st Avenue Bridge over Clear Creek to allow water at the 100 year flood level to pass underneath.
  • Improved the storm sewer system on 1st Avenue from Clear Creek to 6th Street.
  • Constructed four storm water pump stations along the Iowa River from Clear Creek to Interstate 80. These pump stations provide gates that are closed to stop Clear Creek from backing up into the City’s gravity storm water collection system when Clear Creek water levels are high; they also pump out local rainfalls when the gates are closed.
  • Constructed earthen berms for flood protection along the former Edgewater Drive.
  • Installed duckbills and sluice gates in 10 locations in the existing storm water system to prevent back-up of high water levels in the Iowa River and Clear Creek from flooding surrounding neighborhoods.
  • Constructed earthen berms, permanent and removable flood walls along the north side of Clear Creek from Highway 6 to 1st Avenue and along Biscuit Creek from Clear Creek to 5th Street, and retention ponds along Biscuit Creek.
  • Constructed two new storm water pump stations on Clear Creek west of 1st Avenue, upgraded two existing storm water pump stations, and flood-proofed the 3rd Avenue sanitary sewer lift station.
  • Constructed flood protection improvements along the Iowa River from west of Rocky Shore Drive to the north end of the Iowa River Power Company Restaurant parking lot. This project raised the CRANDIC railroad embankment, raised and lengthened the CRANDIC railroad Clear Creek Bridge, and constructed earthen berms and permanent and removable flood walls.
  • Constructed a floodwall on the south side of Clear Creek between 1st Avenue and the CRANDIC Railroad.
  • Reconstructed and elevated 5th Street from 3rd Avenue to 4th Avenue as it crosses Biscuit Creek.
  • A combination of permanent and temporary flood protection on the south side of Clear Creek from 1st Avenue to Highway 6 is planned for construction in  2016 and 2017.
  • Two existing storm water pump stations south of Highway 6 at Clear Creek will be improved during 2017 and 2018.