Groundwater levels fall across western, south-central Kansas

LAWRENCE — Preliminary groundwater level measurements compiled by the Kansas Geological Survey show an overall decline of almost a foot across the High Plains aquifer region in western Kansas in 2024. All areas in western and south-central Kansas experienced declines in water levels.

"For the most part, we've been on the dry side the last five years, and this year especially so in northwest Kansas. Water levels reflect that,” said Brownie Wilson, KGS water-data manager. “Having said that, we did get some great rains across the state in November. In contrast to the Ogallala aquifer, in some areas like south-central Kansas where sandy soils are common and the aquifer is close to the land surface, the aquifer can respond to precipitation events. Talking with groundwater management district managers in south-central Kansas, November rains helped raise the water levels several feet in a matter of months.”

Most parts of the state saw well below average precipitation in March and April of 2024 as the growing season got underway. Pockets of moisture fell in May and June (notably in portions of southwest Kansas), and drier than average conditions returned in the summer and early fall before the substantial rains of November.

The KGS, based at the University of Kansas, and the Division of Water Resources (DWR) of the Kansas Department of Agriculture measure water levels in about 1,400 wells every year to monitor the health of the High Plains aquifer and other aquifers in western and south-central Kansas.

Those measurements showed an overall decline of 0.91 feet across the region, marking the fifth straight year of overall declines. Groundwater levels across the region fell 0.17 feet in 2023, 1.9 feet in 2022, about a foot in 2021 and 0.85 feet in 2020. Annual change in groundwater levels across the region averaged -0.42 feet from 1996 to 2024.

The High Plains aquifer is a network of water-bearing rock that extends into eight states. In Kansas, the aquifer comprises three components — the Ogallala aquifer, the Great Bend Prairie aquifer and the Equus Beds. Of these, the Ogallala underlies most of western Kansas and consists mainly of the Ogallala Formation, a geologic unit that formed from sediment eroded off the uplifting Rocky Mountains.

Most of the wells in the network monitored by the KGS and DWR are within the boundaries of the state’s five groundwater management districts, which are organized and governed by area landowners and local water users to address water-resources issues.

“On a regional scale, most areas of the aquifer were down more than their long-term averages. The exception to that was in southwest Kansas,” Wilson said.

Although southwest Kansas GMD 3 experienced the greatest average drop in water levels in 2024, at 1.36 feet, it was the only district to see declines less than its long-term average. The average annual decline in the district’s water level from 1996 to 2024 was 1.67 feet. It saw average declines of 0.19 feet in 2023 and 2.83 feet in 2022.

GMD 3 includes all or part of Finney, Ford, Grant, Gray, Hamilton, Haskell, Kearny, Meade, Morton, Seward, Stanton and Stevens counties. Most of the wells monitored in the district are drilled into the Ogallala aquifer, except in a few areas where they can also draw from the deeper Dakota aquifer.

Northwest Kansas GMD 4 experienced a decline of 1.16 feet in 2024, after an increase of 0.35 feet in 2023, a year in which the district saw well-above-average precipitation. GMD 4 water levels declined by 1.32 feet in 2022. Average annual declines in the district from 1996 to 2024 were 0.47 feet.

GMD 4 covers Sheridan, Sherman, Thomas and parts of Cheyenne, Decatur, Gove, Graham, Logan, Rawlins and Wallace counties. Groundwater there is pumped from the Ogallala aquifer and shallow alluvial sources associated with streams.

Western Kansas GMD 1, where the majority of wells are drilled into the Ogallala aquifer, saw a decline of 0.62 feet in 2024, after an increase of 0.27 feet in 2023 and a decline of 1.13 feet in 2022. From 1996 to 2024, water levels fell an average 0.53 feet per year.

GMD 1 includes portions of Greeley, Lane, Scott, Wallace and Wichita counties. Water levels in the district, one of the first areas of the state to have large-capacity wells drilled in the 1940s-1950s, have fallen to a point that yields for irrigation have greatly diminished.

Water levels in south-central Kansas saw a fifth straight year of larger than normal decline rates amid continuing drought conditions. This area typically sees more precipitation than the western part of the state, but total rainfall throughout the region fell short of average in 2024.

Equus Beds GMD 2, a significant source of water for Wichita, Hutchinson and surrounding towns, saw a decline of 0.41 feet in 2024. Levels in the district fell 1.62 feet in 2023 and 2.11 feet in 2022. GMD 2 covers portions of Harvey, McPherson, Reno and Sedgwick counties.

Water levels in Big Bend GMD 5, centered on the Great Bend Prairie aquifer, fell 0.51 feet in 2024 after declines of 1.12 feet in 2023 and 2.32 feet in 2022. GMD 5 includes Pratt and Stafford counties and parts of Barton, Edwards, Kiowa, Pawnee, Reno and Rice counties.

Since 1996, when the state began administrating the water-level monitoring program, water levels in south-central Kansas, including GMDs 2 and 5, have remained relatively stable. The aquifer there is relatively close to the land surface and sandy soils are abundant, allowing precipitation during average or above average years to make its way into the aquifer. Average annual water level declines from 1996 to 2024 were 0.03 feet in GMD 2 and 0.19 feet in GMD 5.

The KGS visited 576 well sites in western Kansas, and DWR staff from field offices in Stockton, Garden City and Stafford measured 218, 262, and 343 wells, respectively, in western and south-central Kansas. Most of the wells, spread over 49 counties, are used for irrigation and have been measured for decades with landowners’ permission.

Measurements are taken primarily in January, when water levels are least likely to fluctuate due to seasonal irrigation. The measurement results, available on the KGS Water Well Levels web page, are provisional and subject to revision based on additional analysis.

The KGS is a nonregulatory research and service division of KU. KGS researchers study and provide information about the state’s geologic resources and hazards, including groundwater, oil and natural gas, critical materials and earthquakes.

For more information, contact Brownie Wilson, bwilson1@ku.edu.