New satellite data shows that groundwater depletion isn’t as severe as previously thought. The drought is what is causing drops in soil moisture. Yes, there has been water loss. However the cause is natural and not due to humans. As an aside, Los Angeles, Las Vegas, Phoenix, and Tucson are using less water than they did twenty years ago even though they’ve had big increases in population. There have been huge advances in water conservation and reuse. Las Vegas recycles all indoor water, pumping it back into Lake Mead to be used again.
Large changes in soil moisture as a result of drought, rather than human groundwater pumping, [is] the explanation for a significant portion of water losses identified by NASA GRACE satellite observations. This is especially true in the Upper Colorado River Basin. In the Lower Basin, the picture is more complex, with some groundwater losses in parts of rural Arizona, balanced by stable or rising aquifers in the state’s heavily populated and heavily farmed central valleys.