Document Type


Date of Degree

Fall 2011

Degree Name

MS (Master of Science)

Degree In

Civil and Environmental Engineering

First Advisor

Weber, Larry J.

Second Advisor

Young, Nathan C.

First Committee Member

Bradley, Allen A.

Second Committee Member

Krajewski, Witold F.


Currently the Iowa Flood Center (IFC) of the University of Iowa is working in conjunction with the Iowa Department of Natural Resources (IDNR) to create statewide floodplain maps. The IFC has set up a four year plan to construct flood inundation maps for 85 of the 99 counties within the state of Iowa, with the final goal of creating maps acceptable by FEMA. High resolution statewide LiDAR information provides a base dataset from which floodplain maps are produced. Stream centerline data is extracted from a DEM produced by the LiDAR dataset. The centerline information is used in both this project and as a replacement for the USGS NHD streamline for the state. Stream flow estimation for a range of annual exceedance discharges are produced through a USGS recommended combination of regional regression analysis weighted by gage influence. Water surface elevations are produced for each of the annual exceedance discharges through the use of a HEC-RAS one dimensional steady flow model. Flood boundaries are the final product created by HEC-GeoRAS though a comparison of a TIN produced from the water surface elevations and the ground surface DEM. Final FEMA acceptable DFIRM's are produce by the IDNR and submitted to FEMA for adoption into the NFIP.


Flood, HEC-RAS, LiDAR, Mapping, Regression


xi, 144 pages


Includes bibliographical references (pages 142-144).


Copyright 2011 Nicholas Wayne Thomas