Projected Changes in Flood Peak Discharge Across Iowa: A Flood Frequency Perspective

Numerous modeling studies point to an intensification of the hydrological cycle under projected climate warming, with increasing frequency of extreme events, including heavy rainfall and flooding. Recently, the occurrence of extreme flooding has becoming the norm rather than the exception, with the 2008 Eastern Iowa flood representing the “poster child” for this catastrophic situation: during this event, for instance, the eastern half of our state experienced the closure of a number of roads, including Interstate 80. So, what would projected changes in flooding mean for the Iowa Department of Transportation (IDOT) and the bridges and structures that constitute Iowa’s highway system? How resilient are these highway structures to different climate warming scenarios? Addressing these questions requires flood frequency analysis. The current methodology relies on the guidelines by Bulletin 17C. However, issues related to regionalization of at-site estimates as well as accounting for the projected changes in the climate system have received little attention despite the potentially large impacts, including to the IDOT’s infrastructure. The proposed approach builds on methodologies and datasets with which the research team have extensive experience. Specifically, the proposed work focuses on the examination of the projected changes in flooding across Iowa using two complementary approaches: one based on the hydrologic model developed by the Iowa Flood Center (IFC), and one based on the statistical relationship between flooding and climate drivers. The focus will be on high-resolution and downscaled outputs from CMIP5 (Fifth Coupled Model Intercomparison Project) and CMIP6 (Sixth Coupled Model Intercomparison Project), and different scenarios.


    • English


    • Status: Active
    • Funding: $313,923.00
    • Contract Numbers:


    • Sponsor Organizations:

      University of Iowa

      Department of Civil and Environmental Engineering
      4105 Seamans Center for the Engineering Arts and Sciences
      Iowa City, IA  United States  52242
    • Managing Organizations:

      Iowa Department of Transportation

      800 Lincoln Way
      Ames, IA  United States  50010
    • Project Managers:

      Clute, Khyle

    • Performing Organizations:

      University of Iowa, Iowa City

      IIHR- Hydroscience & Engineering
      307 C. Maxwell Stanley Hydraulics Lab
      Iowa City, Iowa  United States  52242
    • Principal Investigators:

      Villarini, Gabriele

      Krajewski, Witold

    • Start Date: 20200301
    • Expected Completion Date: 20230228
    • Actual Completion Date: 0

    Subject/Index Terms

    Filing Info

    • Accession Number: 01735898
    • Record Type: Research project
    • Source Agency: Iowa Department of Transportation
    • Contract Numbers: 20-SPR2-002
    • Files: RIP, STATEDOT
    • Created Date: Apr 7 2020 2:00PM