A study led by University of Arizona researchers shows that decades of groundwater pumping by humans has depleted Tucson-area aquifers far more than natural climate variation. Published in the journal Water Resources Research, the study provides the first multi-millennial reconstruction for the region that places human impacts on groundwater into long-term context.
“This is the first time we’ve been able to get a record of the water table through time,” said Jennifer McIntosh, senior author and the Thomas Meixner Endowed Chair of Hydrology and Atmospheric Sciences in the College of Science.
Since the climactic period known as the Last Glacial Maximum—about 20,000 years ago—precipitation has continuously recharged the aquifer under Tucson, the study concluded. During dry climate periods, less precipitation seeped back into the aquifer, and the water table dropped by as much as 105 feet (32 meters), compared with the levels in wetter periods…