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Land Use and Urban Recharge in the Brushy Creek Watershed

Jonathan Snatic

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Urban Recharge

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Urban Recharge

Leaking water mains and sewers

Infiltration of excess irrigation

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Brushy Creek Basin

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Land Use 1992

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Land Use 2001

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Contributing Zone

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LCRA- municipal supply

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Llano Uplift

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Llano Uplift

Llano RiverPedernales River

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(87Sr/86Sr)MIX = (87Sr/86Sr)A ( fA) (SrA/ SrM) + (87Sr/86Sr)B (1-fA) (SrB/SrA)

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Brushy Creek Basin

Lake Creek Mason Creek

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• Can determine the urban recharge component to base flow in the Brushy Creek Basin.– Sampling– 2 component mixing model

• Is there a correlation between urban recharge and land use in the sampled watersheds?– Delineate sampled watersheds – Compare land use in watersheds

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30m DEM

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NHD Flowlines

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Flow Accumulation

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World Map

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Sample Locations- Point Delineation

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Watersheds

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Land Use

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Urban vs. Rural Land Use

Urban

• 100- Single Family Res.

• 300- Commercial

• 400- Office

• 530- Misc. Industrial

Rural

• 900- Undeveloped

• 160- Large Lot Single Family

• 910- Agricultural

• 710- Parks

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30 40 50 60 70 80 90 1000

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R² = 0.984303734542969

Correlation

% Urban Recharge in Base Flow

% U

rban

Land

Use

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Questions?