Water Resources NSDI Node

Vulnerability of shallow ground water and drinking-water wells to nitrate in the United States: Model of predicted nitrate concentration in shallow, recently recharged ground water

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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