Model Bathymetry Lake Travis: A Sinuous Reservoir

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Model BathymetryLake Travis A Sinuous Reservoir

• Bridget Wadzuk
• March 29, 2001

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Introduction

• Reservoir Characteristics
• Models
• CE-QUAL-W2 (COE)
• 2-D
• Segmented bathymetry
• ELCOM (Hodges/UWA)
• 3-D
• Cartesian grid bathymetry

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Taken from CE-QUAL-W2 V3 Users Manual
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Problem

• Bathymetry from ArcView Cartesian grid (plan
  view)
• Need to get into a format that is accepted by
  CE-QUAL-W2 (profile view)
• STRAIGHTENED
• BATHYMETRY

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Theory

• Relation of physical and radial space
• 11 correspondence
• Radial lines
• Arc lengths

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Easier Said

• Choosing a grid
• Resolution over scale of Lake Travis
• Approach using Matlab
• Select points for centerline
• Spline points to a smooth curve
• Compute normal radial lines
• Check for crossing of radial lines
• Repeat process until no crossings
• Use intervals for bathymetry

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Bathymetry (original)
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Centerline Points
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Radial Lines (1)
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Radial Lines (2)

• Radius of Curvature, Ro
• Channel Width, ?
• Normally, ?/ Ro lt 1
• Ignore curvilinear term in sinuous systems
• Unacceptable, ?/ Ro gt 1
• Thalweg must be adjusted

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Radial Lines (3)
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Straightened Bathymetry
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Yet To Come

• Change approach to a GIS method
• Use a smaller, more concise area
• Lake LBJ
• Less computationally intensive