Floodplain%20Analysis%20with%20ArcGIS%20Model%20Builder

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Floodplain Analysis with ArcGIS Model Builder

• Donghyun Rim
• University of Texas at Austin

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What is floodplain and why is it important?

• Floodplain - the lowland adjacent to a river,
  lake or ocean.  
• Floodplains are designated by the frequency of
  the flood that is large enough to cover them.
• The National Flood Insurance Program has
  established a minimum standard of protection
  against the 100-year flood.
• Flood damage reduction critical interest

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Work Site
Austin Waller Creek
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Conceptual Process

1. Rainfall input
2. Topologic dataset of the watershed of Waller
   Creek
3. Runoff Simulation by using HEC-HMS
4. Calculation of water surface-elevations along the
   channel with HEC-RAS
5. Transformation of water-surface elevation to a
   unique inundation area known as flood plain

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Marvelous Toolbox-MAP2MAP
Developed by Oscar Robayo
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Rainfall Map to Flood Inundation Map
Transfer Data from NEXRAD Cell to Subbasins
Import into Geodatabase
NEXRAD Rainfall Data
Export Timeseries of Rainfall to HEC-DSS
Streamflow Hydrographs
HEC-HMS
Runoff Data (HEC-DSS) to GIS
Water Surface Elevation File
HEC-RAS
Import to GIS as XML Format
Convert WSE to WS TIN
Polygon as Inundated Area
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Data Collection
1. NEXRAD Rainfall Data
2. Topological Hydrography
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3. HEC-HMS
4. HEC-RAS
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5.DEM
6. Orthographic Photo
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Creation of Compatible Data
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Result for Rosillo Creek
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Future Work

• Use of 10 m cell DEM for delineation of
  Watershed.
• Perform Map2Map run for Waller Creek.
• Use of rainfall for another time period

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Special thanks to

• Dr. Maidment
• Oscar Robayo
• Laton Carr