The Pecos River Basin alluvial aquifer, hereinafter referred to as the "Pecos aquifer", is located in western Texas and southeastern New Mexico. The aquifer is primarily composed of alluvial sand and gravel deposits mantled by sand and silt. The Pecos aquifer overlies Permian, Triassic, and Cretaceous-age rocks. The saturated thickness of the aquifer ranges from 0 to 1000 feet. The aquifer can provide highly productive wells where transmissivity is high and saturated thickness is adequate (HA730-E). This data release contains the following feature datasets: Georeferenced images: 1. i_12PCSRVR_bot.tif: Scanned figure of altitude contour lines representing the bottom of the Pecos aquifer. The original figure was from the Groundwater Atlas (HA730-E) figure 28. Extent shapefiles: 1. p_12PCSRVR.shp: Polygon shapefile containing the areal extent of the Pecos aquifer (Pecos_AqExtent). The extent file contains no aquifer subunits. Contour line shapefiles: 1. c_12PCSRVR_bot.shp: Contour line dataset containing altitude values, in feet reference to National Geodetic Vertical Datum of 1929 (NGVD29), across the bottom of the Pecos aquifer (HA730-E). These data were used to create the ra_12PCSRVR_bot.tif altitude raster dataset. Altitude raster files: 1. ra_12PCSRVR_top.tif: Altitude raster dataset of the top of the Pecos aquifer. The altitude values are in meters reference to North American Vertical Datum of 1988 (NAVD88). The top of the aquifer is assumed to be land surface (NED, 100-meter) based on available data. 2. ra_12PCSRVR_bot.tif: Altitude raster dataset of the bottom of the Pecos aquifer. The altitude values are in meters reference to NAVD88. Depth raster files: 1. rd_12PCSRVR_top.tif: Depth raster dataset of the top of the Pecos aquifer. The depth values are in meters below land surface (NED, 100-meter). The top of the aquifer is assumed to be at land surface (NED, 100-meter) based on available data. 2. rd_12PCSRVR_bot.tif: Depth raster dataset of the bottom of the Pecos aquifer. The depth values are in meters below land surface (NED, 100-meter).