1 / 20

WATERWAYS AND BRIDGES IN TEXAS

WATERWAYS AND BRIDGES IN TEXAS. CE 394K 11-22-05 Dr. Maidment. “Final” Presentation by: Brandon Klenzendorf. Background. TxDOT to use crash-tested bridge rails May impact FEMA 100-year floodplains Cause for map revisions – time and money!

elton
Download Presentation

WATERWAYS AND BRIDGES IN TEXAS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. WATERWAYS AND BRIDGES IN TEXAS CE 394K 11-22-05 Dr. Maidment “Final” Presentation by: Brandon Klenzendorf

  2. Background • TxDOT to use crash-tested bridge rails • May impact FEMA 100-year floodplains • Cause for map revisions – time and money! • Need to determine how bridge rails affect water surface profiles

  3. TxDOT Design Frequencies TxDOT Hydraulic Design Manual

  4. Project Purpose • In order to solve this problem, we need to predict… • Hydraulic impact of crash-tested bridge rails • 100-year peak flood discharges • Determine peak discharge for 100-year return period flood • Use GIS and NFF programs to gain info on flood discharges

  5. GIS Data Collection • State of Texas HUCs from TNRIS • http://www.tnris.state.tx.us/ • Major highway network from TNRIS • Major stream network from TNRIS • DEMs for selected bridges from USGS • http://seamless.usgs.gov/

  6. 1 3 7 10 4 2 8 11 5 9 6

  7. ArcHydro Tools • DEM processing • Problems with gaps in stream layer • Drainage line creation • Batch point watershed delineation • Longest upstream length • Upstream and downstream elevations

  8. Bridge 1 Problems!

  9. USGS NFF Program • National Flood Frequency Program • Estimates the magnitude and frequency of flood peak discharges and hydrographs • 2, 5, 10, 25, 50, 100, and 500-year frequency floods • Uses Visual Basic and regression equations specific for each state • FREE!!! • http://water.usgs.gov/software/nff.html

  10. NFF Program Parameters • Drainage Area (A) – area (mi2) contributing to flow at the bridge • Shape Factor (SH) – ratio of stream length squared (mi2) to drainage area (mi2) • Represents stream length to average width • Stream Slope (SL) – change in elevation (ft) divided by steam length (mi)

  11. Hydrologic Regions • Determined based on physiography and climatic conditions • Each hydrologic region has range of applicable parameters • Hydrologic Region 1 - Q100=371A0.847SH-0.307

  12. Determined NFF Parameters

  13. NFF Interface

  14. Flood Region Map

  15. NFF Results • 100-year hydrograph for five bridges • Bridge 5 has largest peak, but third largest area • Bridge 3 has second lowest peak, but largest area 5 1 4 3 2

  16. Completed Work • Geodatabase of Texas rivers, highways, and HUCs • ArcHydro tools for all bridges • Batch point watershed delineation for all bridges • Partial completion of longest stream length • Partial completion of NFF analysis

  17. Future Work • Longest stream lengths for remaining Hydrologic Regions • NFF analysis for all bridges • Comparison of results • Analyze errors in DEMs, HUCs, and bridge locations • Write final report

  18. Questions ?

More Related