Major aquifers, well yields, estimated natural recharge, estimated water in storage, number of index wells and date of last water-level sweep are shown in Table 3.11-3.  Figure 3.11-6 shows aquifer flow direction and water-level change between 1990-1991 and 2003-2004.  Figure 3.11-7 contains hydrographs for selected wells shown on Figure 3.11-6.  Figure 3.11-8 shows well yields in three 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.  For more information on groundwater in the basin see San Bernardino Valley Basin Hydrology.

Major Aquifers

• Refer to Table 3.11-3 and Figure 3.11-6.
• The major aquifers in the basin are recent stream alluvium and volcanic rock.
• Artesian wells and springs support wetlands in this basin near the border with Mexico.
• Flow direction is generally from the north to the south.

Well Yields

• Refer to Table 3.11-3 and Figure 3.11-8.
• As shown on Figure 3.11-8 well yields in this basin range from less than 100 gallons per minute (gpm) to 1,000 gpm.
• One source of well yield information, based on three reported wells, indicates that the median well yield in this basin is 450 gpm, however the range is quite large, 22-600 gpm.

Natural Recharge

• Refer to Table 3.11-3.

• The natural recharge estimate for this basin is 9,000 acre-feet per year (AFA).

Water in Storage

• Refer to Table 3.11-3.

• Storage estimates for this basin range from 1.6 million acre-feet (maf) to 2.0 maf to a depth of 1,200 feet. 

   

Water Level

• Refer to Figure 3.11-6.  Water levels are shown for wells measured in 2003-2004.
• The Department annually measures four index wells in this basin.  Hydrographs for two of these wells are shown in Figure 3.11-7. More recent hydrographs of the index wells may be available through the Department's GWSI webpage
• Depth to water was measured for three wells in this basin in 2003-2004 and varies from 612 feet in the north central portion of the basin to 30 feet along the border with Mexico.

Click to view Table 3.11-3 Groundwater Data for the San Bernardino Valley Basin

Click to view Figure 3.11-6 San Bernardino Valley Basin Groundwater Conditions

Click to view Figure 3.11-7 San Bernardino Valley Basin Hydrographs Showing Depth to Water in Selected Wells

Click to view Figure 3.11-8 San Bernardino Valley Basin Well Yields

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