In order to evaluate the feasibility of artificial recharge in the Big Bear Valley, a phased investigation program was developed for multiple potential sites. The program included field reconnaissance, borehole drilling and testing, monitoring well construction, and pilot testing.  Key criteria for evaluating recharge feasibility included:  horizontal and vertical extent of low permeability layers, infiltration rates of applied recharge water, aquifer characteristics which affect the storage and recovery of ground water, changes in the quality of recharge water in the vadose and saturated zones, and seepage rates and stored water residence time.

Pilot testing results show that recharge water introduced during pilot testing reached the ground water within a few days of introduction to the pilot spreading basin.  Soil moisture instrumentation showed that, in some cases, percolating water reached deeper portions of the unsaturated zone first and ponded up into the more shallow sediments before saturating the entire soil column beneath the basin.  A surface infiltration rate of approximately 3 ft per day was maintained throughout the test.    Analysis of artificial recharge scenarios using a calibrated ground water flow model show that the recharged water can be stored in the aquifer system for more than 6 months before extraction, a major regulatory criteria for recycled water.  In summary, the testing showed that artificial recharge is feasible in this mountain area.