CRWR-FloodMap

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CRWR-FloodMap
CRWR-PrePro
AvRAS
Digital Map Database
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Waller Creek DEM
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Waller Creek HMS Model
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Flood Plain Mapping
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HEC-RAS Background

• River Analysis System model of the U.S. Army
  Corps of Engineers
• Input cross-section geometry and flow rates
• Output flood water elevations

Cross-Section Schematic
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HEC-RAS Cross-Section Description

• Points describe channel and floodway geometry
• Bank station locations
• Water surface elevations and floodplain
  boundaries

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3-Dimensional River Channel
ProfileLine
Each point has (x,y,z) coordinates
CrossSectionLine
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Connecting HMS and RAS
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Discharge at a Particular Cross-Section
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CRWR-FloodMap
CRWR-PrePro
AvRAS
Digital Map Database
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HEC-RAS Output

• Graphical

• Text File

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HEC-RAS Data Translation

• Data translation from HEC-RAS text file to dbase
  table
• Bank and floodplain boundaries measured from
  stream centerline

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Digital Stream Mapping

• Digital orthophotograph and road coverage used as
  a base map
• User digitizes stream with mouse
• Boundary points define the RAS stream

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Floodplain Mapping Plan View
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3D Terrain Modeling Procedure
Outside Channel Raster
Inside Channel Vector
Result TIN
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3D Terrain Modeling Procedure

• DEM raster to vector conversion
• Form a cross-section bounding polygon
• Intersect DEM points with bounding polygon and
  delete selected points

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3D Terrain Modeling
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3D Terrain Modeling
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Floodplain Mapping Plan View
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Floodplain Mapping Plan View
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Animated Flood Map 2-D View
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Floodplain Mapping 3-D View
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3D Terrain Modeling Ultimate Goal
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Real-time flood emergency mapping
Nexrad radar rainfall input
Real time
Precomputed flood map library
Offline
Flood hydrology analysis system