Groundwater

The Southwest Gravity Program provides high-precision time-lapse gravity (repeat microgravity) data for hydrologic studies in the southwestern US. Recent projects include monitoring recharge underneath ephemeral-stream channels, monitoring aquifer-storage change in unconfined and compressible aquifers, measuring storage change at surface-spreading and injection-well artificial-recharge facilities...

The U.S. Geological Survey Arizona Water Science Center in cooperation with Tucson Water has monitored water-level and aquifer compaction at several wells in Avra Valley and Tucson Basin since about 1980. The purpose of the data collection is to document compaction of the aquifer system in response to stresses induced by water-level change, provide control for satellite-based observations of land...

The USGS seeks to increase understanding of the groundwater system in the vicinity of the Lower Colorado Water Supply Project well field and to estimate future groundwater levels and total dissolved solids concentrations in the wells and the long-term viability of the Lower Colorado Water Supply Project.

Tucson Water’s Santa Cruz River Heritage Project releases up to 3,150 acre-feet a year of reclaimed water into the Santa Cruz River channel near downtown Tucson, AZ, much of which is expected to recharge to the subsurface through the channel bottom. Tracking the movement of recharged water is necessary to limit the dispersal of that water within specific target boundaries, and to enable resource...

In partnership with the Flood Control District of Maricopa County and as part of the Urban Waters Federal Partnership, the US Geological Survey is collecting water-quality and water-level data to help characterize the shallow groundwater and surface water along the Lower Gila River. Water sampling and continuous monitoring of specific conductance, surface water, and shallow groundwater level...

USGS, in cooperation with the Albuquerque Bernalillo County Water Utility Authority, began repeat microgravity measurements in 2015 to monitor aquifer-storage changes in the Albuquerque basin.

The Big Chino Subbasin is a groundwater basin that includes the Verde River headwaters in Yavapai County in north-central Arizona. Groundwater in the Big Chino Valley discharges to wells (by pumping), by evapotranspiration, and to the upper Verde River springs, which form the headwaters of the Verde River. Groundwater also discharges to short perennial reaches of Williamson Valley Wash, Walnut...

Potential changes in groundwater levels in Pipe Spring National Monument are monitored via three observation wells by the U.S. Geological Survey (USGS) in cooperation with the National Park Service (NPS).

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...

The Arizona Water Science Center is monitoring aquifer-storage changes and land subsidence within the Tucson Active Management Area (AMA). Land-surface elevation change is monitored at a network of benchmarks throughout the Tucson AMA by measuring changes in land surface elevation over time (approximately annually) with Interferometric Synthetic Aperture Radar (InSAR). Aquifer-storage change is...

The AzWSC has been collecting groundwater data in Arizona for several decades and maintains a publicly accessible database for water-level data for several thousand sites. With the data it collects and maintains, the AzWSC is able to produce groundwater models that assess future effects of groundwater development in the complex aquifers of Arizona.