CRWR-FloodMap

ArcViewDigital

ElevationModel

HEC-HMSFlood

discharge

HEC-RASWatersurfaceprofiles

ArcViewFlood

plain maps

CRWR-PrePro AvRAS

Digital Map Database

Waller Creek DEM

Waller Creek HMS Model

Flood Plain Mapping

HEC-RAS: BackgroundRiver Analysis System model of the U.S. Army Corps of

Engineers Input = cross-section geometry and flow ratesOutput = flood water elevations

Floodway Floodway

Left Bank Station

Flood Water Surface

Right Bank Station

Normal Water Surface

Main Channel

Cross-Section Schematic

Points describe channel and floodway geometry

Bank station locations

Water surface elevations and floodplain boundaries

HEC-RAS: Cross-Section Description

3-Dimensional River Channel

CrossSectionLine

ProfileLine

Each point has (x,y,z)coordinates

Connecting HMS and RAS

Discharge at a Particular Cross-Section

CRWR-FloodMap

ArcViewDigital

ElevationModel

HEC-HMSFlood

discharge

HEC-RASWatersurfaceprofiles

ArcViewFlood

plain maps

CRWR-PrePro AvRAS

Digital Map Database

HEC-RAS: OutputText FileGraphical

Data translation from HEC-RAS text file to dbase table

Bank and floodplain boundaries measured from stream centerline

HEC-RAS: Data Translation

Digital orthophotograph and road coverage used as a base map

User digitizes stream with mouse

Boundary points define the RAS stream

Digital Stream Mapping

Floodplain Mapping: Plan View

3D Terrain Modeling: Procedure

Inside Channel: Vector Outside Channel: Raster

Result: TIN

DEM raster to vector conversionForm a cross-section bounding

polygonIntersect DEM

points with bounding polygon and delete

selected points

3D Terrain Modeling: Procedure

3D Terrain Modeling

3D Terrain Modeling

Floodplain Mapping: Plan View

Floodplain Mapping: Plan View

Animated Flood Map 2-D View

Floodplain Mapping: 3-D View

3D Terrain Modeling: Ultimate Goal

Real-time flood emergency mapping

Flood hydrologyanalysis system

Nexrad radarrainfall input

Precomputedflood map

library

Real time

Offline