Geophysics Monitoring

The Arizona Water Science Center is monitoring aquifer-storage changes at an artificial recharge facility operated by Tucson Water in southeast Tucson. Aquifer-storage change is monitored by measuring changes in gravity over time at the same network of benchmarks. As water is added or removed from the aquifer, there is a change in mass and a corresponding measurable change in gravity.

The City of Phoenix has traditionally relied on surface-water supplies from the Salt, Verde, and Colorado River watersheds. To increase water-supply resiliency and flexibility, the City is expanding its Artificial Storage and Recovery (ASR) operations in the north Phoenix area. USGS is measuring small changes in gravity caused by groundwater-storage changes to better understand where and when...