Summary

Description

This data set represents the estimated percentage of the 1-km grid cell that is covered by or subject to the agricultural conservation practice (CP447), Irrigation System by Tailwater Recovery (ISTR) on agricultural land by county. Irrigation System by Tailwater Recovery is described as "a planned irrigation system in which all facilities utilized for the collection, storage, and transportation of irrigation tailwater for reuse have been installed." (U.S. Department of Agriculture, 1995) Tailwater is the area immediately below a dam where the river water is cooler than normal and rich in nutrients. This data set was created with geographic information systems (GIS) and database management tools. The acres on which ISTR's are applied were totaled at the county level in the tabular NRI database and then apportioned to a raster coverage of agricultural land within the county based on the Enhanced National Land Cover Dataset (NLCDe) 1-kilometer resolution land cover grids (Nakagaki, 2003). Federal land is not considered in this analysis because NRI does not record information on those lands.