Floodplain Mapping using TINs Triangulated Irregular Networks (TINs) Representation of stream channels using TINs Floodplain delineation using HEC-HMS, HEC-RAS and ArcView
TIN with Surface Features Classroom Waller Creek UT Football Stadium
A Portion of the TIN
Input Data for this Portion Mass Points Soft Breaklines Hard Breaklines
TIN Vertices and Triangles
TIN Surface Model Waller Creek Street and Bridge
3-D Scene
3-D Scene with Buildings
Floodplain Mapping using TINs Triangulated Irregular Networks (TINs) Representation of stream channels using TINs Floodplain delineation using HEC-HMS, HEC-RAS and ArcView
River Modeling River hydraulic modeling provides a tool to study and gain understanding of hydraulic flow phenomena Topographic data describe the geometry of the simulated river system and permit the establishment of model topology HEC-RAS, MIKE 11 all hydraulic models require channel information for model development
River Morphology
Flood Inundation
Floodplain Delineation
Channel and Cross-Section Direction of Flow Cross-Section Channel
ProfileLines Types 1- Thalweg 2- LeftBank 3- RightBank 4- LeftFloodLine 5- RightFloodLine ProfileLines and CrossSections are linked through Channel_ID
TIN as a source of cross-sections
CrossSections
Elements of a Cross-Section Geometry Identifier Georeference Property Supplementary
Floodplain Mapping using TINs Triangulated Irregular Networks (TINs) Representation of stream channels using TINs Floodplain delineation using HEC-HMS, HEC-RAS and ArcView
Floodplain Mapping Approach CRWR-PrePro HEC-GeoRas Water surface profiles ArcView Geometric data Parameters Schematic Flow discharge HEC-HMSHEC-RAS
Purpose Integrate/Validate existing tools for floodplain determination and visualization. –Reduce the dependence on field data. –Improve the floodplain analyses capabilities (lower costs and more accuracy).
Digital Spatial Data ArcView HEC-RASHEC-HMS Digital elevation model (DEM). Stream definition.
CRWR-PrePro ArcView HEC-RASHEC-HMS Watershed delineation. Reach/Watershed parameters determination.
HEC-HMS: Flow Determination ArcView HEC-RASHEC-HMS
HMS-RAS Connection HMS JunctionsRAS Cross-sections ArcView HEC-RASHEC-HMS
HMS-RAS Connection ArcView HEC-RASHEC-HMS (0500, ) HMS Hydrograph RAS Flow Data
Digital Terrain Model: TIN ArcView HEC-RASHEC-HMS Observed points and breaklines for constructing a triangular irregular network (TIN).
Digital Terrain Model: TIN ArcView HEC-RASHEC-HMS Embedding Buildings into the TIN.
GIS-RAS Connection Stream centerline. Banks. Flow paths. Cross sections. ArcView HEC-RASHEC-HMS
GIS-RAS Connection Location of cross sections. ArcView HEC-RASHEC-HMS
Hydraulic Modeling with HEC-RAS RAS stream geometry. Cross-section extracted from the TIN. ArcView HEC-RASHEC-HMS
Hydraulic Modeling with HEC-RAS Resulting water elevations. ArcView HEC-RASHEC-HMS
Floodplain Mapping ArcView HEC-RASHEC-HMS Floodplain for 500 cfs.
Floodplain Mapping 2-D floodplain animation (500 – 5,000 cfs).
Floodplain Mapping 3-D floodplain animation.
Limitations Bridges/culverts: - depend on field data. - data input by hand.
Limitations The accuracy obtained from our TIN is not good enough.
Solutions New technologies (i.e. LADAR) are improving the quality of the digital terrain representations. Source: digital representation of NYC generated by ASI and published by ESRI. New technologies (i.e. LADAR) are improving the quality of the digital terrain representations.