The Configuration of the Base of the Principal Aquifer data consists of two separate layers: the contours layer (baseaq, which depicts the elevation of the base of the aquifer, and the polygons layer (absent), which depicts those areas where the principal aquifer is very thin, or absent. The GIS layer was developed by scanning the original, hand-drawn mylar quadrangles, converting the scanned contours into vectors and "tagging" each vector with the appropriate elevation. Similarly, the polygons depicting those areas where the principal aquifer is either very thin or absent were scanned and converted into polygons. Each of the individual quadrangles were then checked against the original maps for accuracy and appended to create a single, statewide layer.

Download Full Image: 10,200 x 6,600 pixels - 5 Mb

A series of contour lines showing the estimated thickness of the saturated sediments that serve as the source aquifer for domestic and irrigation wells. It was digitized from eleven 1980 USGS 1x2 degree quadrangles and has been used as the 'normal' thickness of the aquifer.

Download Full Image: 10,200 x 6,600 pixels - 3.7 Mb

Prepared from CSD Center Pivot Inventory data base. Data are derived from manually interpreted Landsat Thematic Mapper images. Each year pivots are identified and missing/abandoned pivots are noted. Features include: the legal description, years observed since 1972, Natural Resource District, and county. There are about 33,000 records (most recent year is 1988).

Download Full Image: 10,200 x 6,600 pixels - 3.1 Mb

Prepared from CSD Center Pivot Inventory data base. Data are derived from manually interpreted Landsat Thematic Mapper images. Each year pivots are identified and missing/abandoned pivots are noted. Features include: the legal description, years observed since 1972, Natural Resource District, and county. There are about 33,000 records (most recent year is 1988).

Polygons of generalized-depth-water from ground surface. Prepared by creating two surfaces. The elevation from DEM data, and the elevation of the water table from digitized mapping. The two surfaces are subtracted, forming a derived depth-to-water surface.

Download Full Image: 10,200 x 6,600 pixels - 4.7 Mb

Configuration of the Water Table was prepared in 1980 to serve as a predevelopment baseline for future water use information. It represents the elevation of the top of the saturated zone of the principal aquifer. The data was hand-contoured by CSD geologists using water-level measurements, CSD test-hole logs and water well registrations. The contours are interpretive, done to a standard within one-half of the mapped interval. Digitized from eleven 1979 USGS 1x2 degree quadrangles.

Download Full Image: 10,200 x 6,600 pixels - 5.1 Mb

This statewide water-table coverage reflects more recent, accurate and comprehensive water-level data. The data was compiled primarily from spring 1995 water-level data.

Download Full Image: 10,200 x 6,600 pixels - 5.2 Mb