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Vulnerability of shallow ground water and drinking-water wells to nitrate in the United States: Model of predicted nitrate concentration in U.S. ground water used for drinking (simulation depth 50 meters)

This index contains metadata and spatial data sets for GWAVA-S and GWAVA-DW.

Nolan and Hitt (2006) developed these two national models to predict contamination of ground water by nonpoint sources of nitrate. The nonlinear approach to national-scale Ground-WAter Vulnerability Assessment (GWAVA) uses components representing nitrogen (N) sources, transport, and attenuation. Users should consult the individual metadata file for each data set for details.

GWAVA-S
The GWAVA-S model predicts nitrate contamination of shallow (typically less than 5 meters deep), recently recharged ground water, which may or may not be used for drinking.

Browse graphic for GWAVA-S

INPUT Data Sets for GWAVA-S

Data layer

Metadata

ARCTAR file

WINZIP file

GRIDASCII file

Nitrogen source factors

Farm fertilizer

gwava-s_ffer

gwava-s_ffer.tgz

gwava-s_ffer.zip

gwava-s_ffer.txt.gz

Confined manure

gwava-s_conf

gwava-s_conf.tgz

gwava-s_conf.zip

gwava-s_conf.txt.gz

Orchards/vineyards

gwava-s_orvi

gwava-s_orvi.tgz

gwava-s_orvi.zip

gwava-s_orvi.txt.gz

Population density

gwava-s_popd

gwava-s_popd.tgz

gwava-s_popd.zip

gwava-s_popd.txt.gz

Cropland/pasture/fallow

gwava-s_crpa

gwava-s_crpa.tgz

gwava-s_crpa.zip

gwava-s_crpa.txt.gz

Nitrogen transport factors

Water input

gwava-s_wtin

gwava-s_wtin.tgz

gwava-s_wtin.zip

gwava-s_wtin.txt.gz

Carbonate rocks

gwava-s_crox

gwava-s_crox.tgz

gwava-s_crox.zip

gwava-s_crox.txt.gz

Basalt and volcanic rocks

gwava-s_vrox

gwava-s_vrox.tgz

gwava-s_vrox.zip

gwava-s_vrox.txt.gz

Drainage ditch

gwava-s_ddit

gwava-s_ddit.tgz

gwava-s_ddit.zip

gwava-s_ddit.txt.gz

Slope

gwava-s_slop

gwava-s_slop.tgz

gwava-s_slop.zip

gwava-s_slop.txt.gz

Glacial till

gwava-s_gtil

gwava-s_gtil.tgz

gwava-s_gtil.zip

gwava-s_gtil.txt.gz

Clay sediment

gwava-s_clay

gwava-s_clay.tgz

gwava-s_clay.zip

gwava-s_clay.txt.gz

Attenuation factors

Fresh surface water withdrawal

gwava-s_swus

gwava-s_swus.tgz

gwava-s_swus.zip

gwava-s_swus.txt.gz

Irrigation tailwater recovery

gwava-s_twre

gwava-s_twre.tgz

gwava-s_twre.zip

gwava-s_twre.txt.gz

Histosol soil type

gwava-s_hist

gwava-s_hist.tgz

gwava-s_hist.zip

gwava-s_hist.txt.gz

Wetlands

gwava-s_wetl

gwava-s_wetl.tgz

gwava-s_wetl.zip

gwava-s_wetl.txt.gz

OUTPUT Data Set for GWAVA-S

Model output

gwava-s_out

gwava-s_out.tgz

gwava-s_out.zip

gwava-s_out.txt.gz

GWAVA-DW
The GWAVA-DW model predicts ambient nitrate concentration in deeper ground water supplies used for drinking (simulation depth for data sets here is 50 meters).

Browse graphic for GWAVA-DW

INPUT Data Sets for GWAVA-DW

Data layer

Metadata

ARCTAR file

GRIDASCII file

Nitrogen source factors

Farm fertilizer

gwava-dw_ffer

gwava-dw_ffer.tgz

gwava-dw_ffer.txt.gz

Confined manure

gwava-dw_conf

gwava-dw_conf.tgz

gwava-dw_conf.txt.gz

Orchards/vineyards

gwava-dw_orvi

gwava-dw_orvi.tgz

gwava-dw_orvi.txt.gz

Population density

gwava-dw_popd

gwava-dw_popd.tgz

gwava-dw_popd.txt.gz

Nitrogen transport factors

Water input

gwava-dw_wtin

gwava-dw_wtin.tgz

gwava-dw_wtin.txt.gz

Glacial till

gwava-dw_gtil

gwava-dw_gtil.tgz

gwava-dw_gtil.txt.gz

Semiconsolidated sand aquifers

gwava-dw_semc

gwava-dw_semc.tgz

gwava-dw_semc.txt.gz

Sandstone and carbonate rocks

gwava-dw_sscb

gwava-dw_sscb.tgz

gwava-dw_sscb.txt.gz

Drainage ditch

gwava-dw_ddit

gwava-dw_ddit.tgz

gwava-dw_ddit.txt.gz

Hortonian overland flow

gwava-dw_hor

gwava-dw_hor.tgz

gwava-dw_hor.txt.gz

Attenuation factors

Fresh surface water withdrawal

gwava-dw_swus

gwava-dw_swus.tgz

gwava-dw_swus.txt.gz

Irrigation tailwater recovery

gwava-dw_twre

gwava-dw_twre.tgz

gwava-dw_twre.txt.gz

Dunne overland flow

gwava-dw_dun

gwava-dw_dun.tgz

gwava-dw_dun.txt.gz

OUTPUT Data Set for GWAVA-DW

Model output

gwava-dw_out

gwava-dw_out.tgz

gwava-dw_out.txt.gz

Reference cited
Nolan, B.T. and Hitt, K.J., 2006, Vulnerability of shallow ground water and drinking-water wells to nitrate in the United States: Environmental Science and Technology, vol. 40, no. 24, pages 7834-7840.
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