Major aquifers, well yields, estimated water in storage, number of index wells and date of last water-level sweep are shown in Table 7.7-3. Figure 7.7-5 shows aquifer flow direction and water-level change between 1990-1991 and 2003-2004. Figure 7.7-6 contains hydrographs for selected wells shown on Figure 7.7-5. Figure 7.7-7 shows well yields in five yield categories. A description of aquifer data sources and methods as well as well data sources and methods, including water-level changes and well yields are found in Volume 1, Appendix A.
Major Aquifers
- Refer to Table 7.7-3 and Figure 7.7-5.
- The major aquifer is basin fill.
- Groundwater flow is generally from south to north, with a cone of depression caused by irrigation pumping west of Hope.
Well Yields
- Refer to Table 7.7-3 and Figure 7.7-7.
- As shown on Figure 7.7-7, well yields in this basin are generally greater than 1,000 gallons per minute (gpm).
- One source of well yield information, based on 68 reported wells, indicates that the median well yield is 1,150 gpm.
Natural Recharge
- Refer to Table 7.7-3.
- Natural recharge estimates range from less than 1,000 acre-feet per year (AFA) to between 4,550 acre-feet and 6,050 AFA.
- The largest source of natural recharge is infiltration of runoff from the Bouse Wash and its tributaries (ADWR 1994b).
Water in Storage
- Refer to Table 7.7-3.
- Storage estimates for this basin range from 9.0 million acre-feet (maf) to 27 maf to a depth of 1,200 feet.
Water Level
- Refer to Figure 7.7-5. Water levels are shown for wells measured in 2003-2004.
- The Department annually measures 19 index wells in this basin. Hydrographs for six index wells are shown on Figure 7.7-6.
- The deepest water level shown on the map is 363 feet south of Vicksburg and the shallowest is 75 feet at Bouse.
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Table 7.7-3 Groundwater Conditions for the Ranegras Plain Basin

Figure 7.7-5 Ranegras Plain Basin Groundwater Conditions

Figure 7.7-6 Ranegras Plain Basin Hydrographs Showing Depth to Water in Selected Wells

Figure 7.7-7 Ranegras Plain Basin Well Yields |