Water-level and recoverable water in storage changes, High Plains aquifer, predevelopment to 2017 and 2015–17

The High Plains aquifer underlies 111.8 million acres (about 175,000 square miles) in parts of eight States—Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Water-level declines began in parts of the High Plains aquifer soon after the beginning of substantial groundwater irrigation (about 1950). This report presents water-level changes and change in recoverable water in storage in the High Plains aquifer from predevelopment (about 1950) to 2017 and from 2015 to 2017.

Water-level changes from predevelopment to 2017, by well, ranged from a rise of 84 feet to a decline of 262 feet; the range for 99 percent of the wells was from a rise of 39 feet to a decline of 200 feet. Water-level changes from 2015 to 2017, by well, ranged from a rise of 41 feet to a decline of 21 feet; the range for 99 percent of the wells was from a rise of 14 feet to a decline of 10 feet. The area-weighted, average water-level changes in the aquifer were an overall decline of 16.8 feet from predevelopment to 2017 and a rise of 0.1 foot from 2015 to 2017. Total recoverable water in storage in the aquifer in 2017 was about 2.91 billion acre-feet, which was a decline of about 291.8 million acre-feet since predevelopment and a rise of 0.1 million acre-feet from 2015 to 2017.