Changes in Ground-Water Levels and Storage in the Wichita Well Field Area, South-Central Kansas, 1940-98

Abstract

The Wichita well field was developed in the Equus Beds aquifer northwest of Wichita, Kansas, to supply water to the city. On September 1, 1940, pumping began from 25 wells in the well field. City pumpage increased from then until the early 1950's and between the late 1970's and early 1990's. Since then, city withdrawals from the well field have decreased as withdrawals increased from Cheney Reservoir, the other major water-supply source for the city. Nearby agricultural withdrawals increased substantially in the 1970's and 1980's and, in the 1990's, was similar in magnitude to city withdrawals in the study area although more seasonal and variable in response to changing climatic conditions.

Ground-water withdrawals in the vicinity of the well field caused a large area of water-level declines to develop in the Equus Beds aquifer. Water levels declined from 1940 through the 1950's drought, stabilized in the 1960's and 1970's, continued to decline between the late 1970's and the 1988-92 drought, and reached their maximum to date of as much as 40 feet or more during 1991-93. Loss of ground water in storage since August 1940 followed a pattern similar to water-level declines, with a maximum loss of storage of 255,000 acre-feet reached in January 1993. Water-level declines encompassed an area of about 190 square miles at their maximum in January 1993 and extended from the Arkansas River to the Little Arkansas River in the vicinity of Halstead and Sedgwick. Ground-water levels have since recovered more than 10 feet in some areas and aquifer storage replenished by 79,000 11acre-feet between 1993 and 1998 primarily as a result of decreased city withdrawals.

Additional information on the Equus Beds Project can be found at: http://ks.water.usgs.gov/studies/equus/

To request a paper copy of this publication, email: GS-W-KS_info@usgs.gov