1. CEE 795 Water Resources Modeling and GIS Learning Objectives: Utilize advanced features in HEC Geo-RAS Handouts: Assignments: Exercise #7 Lecture 8: Advanced Features in HEC-GeoRAS March 6, 2006

2. Advanced Features in HEC-GeoRAS 1.Bridges/Culverts 2.Ineffective Flow Areas 3.Blocked obstructions 4.Levees 5.Inline Structures 6.Lateral Structure 7.Storage Areas 1 2 3 4 6 7 5

3. Advanced Features in HEC-GeoRAS BRIDGES/CULVERTS (1) Similar to a cross-section Identifies stationing of bridge Elevation of deck is based on TIN Will need to add data in HEC-RAS

4. Advanced Features in HEC-GeoRAS INEFFECTIVE FLOW AREAS (2) Portions of floodplain that do not convey flow “Dead” zones near bridges

5. Advanced Features in HEC-GeoRAS BLOCKED OBSTRUCTIONS (3) Parts of floodplains permanently remove from flow area Encroachments entered as polygons similar to landuse Example includes development along a river

6. Advanced Features in HEC-GeoRAS LEVEE ALIGNMENT (4) Linear feature that contains the flow Levees are represented but also could be a road One levee per bank Once overtopped, the flow will go laterally 4

7. Advanced Features in HEC-GeoRAS INLINE STRUCTURES (5) Weirs and dams Similar to a bridge May need to adjust elevations depending on accuracy of TIN 5 6

8. Advanced Features in HEC-GeoRAS LATERAL STRUCTURES (6) Similar to weirs Spillover flow from main channel Parallel to river 5 6

9. Advanced Features in HEC-GeoRAS STORAGE AREAS (7) Receives flow from lateral structures Floodplain detention storage Connected with main channel using a lateral structure 5 6