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					Waller Creek Sub-basin

         HMS
                  Review
• Original project idea scrapped
  • Difficult to find adequate GIS data
  • No measured flow data to validate model
    results
• Selected new study area
New Area
         Area Characteristics
• Located on UT campus at 24th and San
  Jacinto
• Dr. Barrett has a monitoring point at basin
  outlet
• Very urban and hydrologically restricted
                   Goals
• Create terrain model in Arcview
• Process terrain model with HEC-geoHMS
• Create working hydrologic model in HEC-
  HMS
• Calibrate model and evaluate results with
  measured rainfall and runoff data
                     Data
• TIN developed by Esteban Azagra
• One-meter DEM (courtesy of Becky)
   • Vegetation
   • Vegetation Removed
• Dr. Barrett’s rainfall and runoff data at
  outlet
        Interesting Questions
• Which data source is best suited for this
  application?
• How can we use HEC-geoHMS?
• How can we create a hydrologic model of a
  restricted basin in a meaningful way?
• How will this model interact with other
  models created in the area?
               Story Begins
• It all started with Esteban Azagra’s TIN
  • Converted TIN to a grid
  • Projected grid from State Plane to UTM
  • Overlayed grid onto a DOQQ for position
    verification
        Conversion
• TIN        • GRID (DEM)
             Projected Grid
• Arc-Info
         Projected Grid
• Code
Overlayed Grid onto DOQQ
          Story Progresses
• Fun with HEC-geoHMS
  • Familiar with HEC-geoHMS
  • Processed terrain data
  • Analyzed final result
Familiar with HEC-geoHMS
Familiar with HEC-geoHMS
      HEC-geoHMS In Action!
• Fill Sinks     • Flow Direction
     HEC-geoHMS In Action!
• Flow Accumulation   • Watershed Delineation
     HEC-geoHMS In Action!
• End Result: Streams!
• Cool, but bad!
• Why?
• Streams are not
  behaving
• No way to modify!
Uh – Oh! What now?
          Pre-Pro In Action!
• Drew in sewer system   • Burned into grid
         The Plot Thickens!

• Becky provides one-meter DEM of study
  area (E00 Files)
• E00 files no longer a mystery to me
   • Import 71
• Becky solves vegetation problems
              Enter LIDAR!

• Vegetated         • Vegetation Removed
 Processing Both Grids in Pre-pro
• LIDAR Flow Direction   • TIN Flow Direction
TIN Product
LIDAR Product
Comparison of Watersheds
Comparison of Streams
   Creation of HMS Schematic
• TIN GIS Model   • TIN Schematic
   Creation of HMS Schematic
• LIDAR GIS Model   • LIDAR Schematic
               The Winner Is:
• LIDAR for HMS
     • Too cumbersome to do both (out of time)
     • LIDAR looks better
•   Checked soil types via SSURGO
•   Developed curve numbers
•   Input hydrologic attributes
•   Ran model
            Intro to HMS
• 3 Parts
               Basin Model
•   Chose SCS for loss and transform methods
•   Chose no baseflow
•   Chose lag method for reach routing
•   Parameters by Hand (and Arcview)
  Getting Soiled With SSURGO
• All for this?
                  • Soil type is Ur (urban)
                     • Either C or D
                  • Land use is urban
                  • Curve numbers are
                    either 94 (C) or 95 (D)
                  • I went with 95
       Hydrologic Parameters
• Sub-basin attributes
  • Notice SLOPES!!
  • Those darned buildings!!!
Hydrologic Parameters By Hand
        (and Arcview)
• Reach Attributes
• Chose lag transform
  • Easy
Meteorologic Model and Control
        Specifications
• User Specified
  Hyetograph
• From 0:00 to 23:55
  10/18/99
• 5 minute increments
                    RESULTS!!!

• After all of this hard
  work: I am ready to
  reap what I have
  sowed
Comparison to measured data:
                 Looks good …
• But I’m off by a factor of 10
   • Units problem?
   • Variability in rainfall?
   • Another problem?
• ???
            I Would Like To:
• Calibrate this model (determine problem)
• Try to use HEC-geoHMS in combination with
  Pre-pro (burn sewers, process with geoHMS)
• Figure out how to make Pre-pro transfer
  hydrologic attributes
• Study how this model fits into models already
  completed
Questions?

				
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posted:6/6/2013
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