Assessing the effect of Land use on the Edward

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Assessing the effect of Land use on the Edwards
aquifer water quality

• Julien Villard
• University of Texas CE 394k

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• Facts about the Edwards aquifer
• 22 to 55 million acre-feet
• Head drop gt 1 foot/day
• Increased environmental concerns
• Urban sprawl
• Overdrafting

Municipal wells in San Antonio, 1895
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Contamination sources
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• Agricultural areas
• Fertilizers, farming, animal dejections
• Urban areas
• Domestic sewage, storm water runoff
• Industrial areas
• Organic industrial wastes

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Well location shapefile
Selection by location
Selection by attribute
Water_QualY
My new shapefile
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Water quality data
Sulfate, Chloride, Fluoride, Nitrate, TDS
Travis, Hays, Comal, Bexar, Medina, Uvalde, Kinney
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(No Transcript)
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Sulfate 2003
Nitrate 2003
Fluoride 2003
Chloride 2003
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USGS Land use data

• Land cover classification system
• Urban
• Low residential
• High residential
• Industrial
• Commercial Industrial
• Agricultural
• Pasture
• Row crops
• Small grains
• Fallow

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Density rasters
Urban density
Agricultural density
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Results

• Urban areas

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Results

• Agricultural areas

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Crop density
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Results

• Crop areas

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Results
Selection of points at less than /- 5 off the
straight line
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Conclusion

• No apparent correlation between land use and
  fluoride, sulfate.
• Small trend between nitrate concentration and
  land use in the recharge area.
• Recharge area more sensitive to land use?

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Any Questions?
My brother was having fun while I was preparing
my slides