Recharge can be estimated using numerical methods, using such codes as HELP, UNSAT-H, SHAW, WEAP, and MIKE SHE.
However, several local environmentalist groups including the Save Our Springs Alliance (SOS) were strongly opposed to the development due to the subdivision's planned location over the recharge zone of the Edwards Aquifer.
The dam provides flood control, groundwater recharge flows and hydroelectricity for the heavily populated San Gabriel Valley in the Greater Los Angeles metropolitan area.