High Plains Aquifer Groundwater Levels Continue to Decline
RESTON, Va., Dec. 17, 2014—The U.S. Geological Survey has released a new report detailing changes of groundwater levels in the High Plains Aquifer. The report presents water-level change data in the aquifer for two separate periods: from 1950 – the time prior to significant groundwater irrigation development – to 2013, and 2011 to 2013.
“The measurements made from 2011 to 2013 represent a large decline,” said Virginia McGuire, USGS scientist and lead author of the study. “This amount of aquifer depletion over a 2-year period is substantial and likely related to increased groundwater pumping.”
In 2011, the total water stored in the aquifer was about 2.92 billion acre-feet, an overall decline of about 267 million acre-feet (or 8 percent) since pre-development. Change in water stored from 2011 to 2013 was an overall decline of 36.0 million acre-feet. The overall average water-level decline in the aquifer was 15.4 feet from pre-development to 2013, and 2.1 feet from 2011 to 2013.
The USGS study used water-level measurements from 3,349 wells for pre-development to 2013 and 7,460 wells for the 2011 to 2013 study period.
The High Plains Aquifer, also known as the Ogallala Aquifer, underlies about 112 million acres (175,000 square miles) in parts of eight states, including: Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. The USGS, at the request of the U.S. Congress, has published reports on water-level changes in the High Plains Aquifer since 1988. Congress requested these reports in response to substantial water-level declines in large areas of the aquifer.
“This multi-state, groundwater-level monitoring activity tracks water-level changes in all eight states through time and has provided data critical to evaluating different options for groundwater management,” said McGuire. “This level of coordinated groundwater-level monitoring is unique among major, multi-state regional aquifers in the country.”