Index Well Program

Purpose

The index well program is designed for developing improved approaches for measuring and interpreting hydrologic responses at the local (section to township) scale in the High Plains aquifer (HPA) in western and south-central Kansas. Index well data is used to calibrate annual manual water level measurements for improved assessment of the High Plains aquifer. This program is administered and monitored by the Kansas Geological Survey.

A major focus of the program has been the development of criteria or methods to evaluate the effectiveness of management strategies at the local scale. Changes in water level—or the rate at which the water level is changing—are considered the most direct and unequivocal measures of the impact of management strategies.

History

The project which began in 2007, utilizes continuous monitoring of water levels in dedicated wells referred to as “index wells” to aid in the evaluation of annual water level measurements and groundwater management strategies at the local scale. The program wells are in strategic locations that help with both short term and long term management decisions. The initial three index wells, installed in 2007, were placed in the southwest, west central and northwest Kansas Groundwater Management District (GMD), each in a distinct water use and hydro-geologic environment. Each well was equipped with a transducer for continuous water level monitoring and connected to a publicly accessible website. The first Local Enhanced Management Area (LEMA), Sheridan County 6 (SD-6) - a seven township area, is supported with four monitoring wells to track the aquifer response to the 20 percent reduction in groundwater pumping, and allow updating the projected useable life of the aquifer locally. Index wells are also in use when possible at water technology farms. In 2016, a total of 24 wells were involved in the network.

Timeline

2007: The initial three index wells were installed and equipped. Data collection and analysis continued for about seven years at these wells. In more recent years the network was expanded
2012: Wells in four monitoring nests (one well from each nest) along the Kansas-Oklahoma state line in GMD3 were added to the network (border wells); additional wells were added from two of these nests (one well per nest)
August 2013: In cooperation with the USGS, telemetry equipment was installed in four of these wells in late 2013
2014: Equipment for real-time monitoring of water levels was installed in an observation well at the KSU research farm in Colby and in a well just north of Belpre in GMD5. In addition, the SD-6 LEMA monitoring wells were incorporated into the network
2016: Three new index wells were installed in GMD1. Telemetry equipment was installed in these wells in June 2016. At the end of the 2016 fiscal year, monitoring data (hourly frequency) from eight full recovery and pumping seasons and one ongoing or completed, depending on location, recovery season had been obtained at the original three index wells; additional water-level data had been acquired from wells (expansion wells)in the vicinity of the three original index wells.
2017: Annual report for the High Plains Aquifer Index Well Program includes the monitoring data (hourly frequency) from nine full recovery and pumping seasons and one ongoing or completed, depending on location, recovery season had been obtained at the original three index wells; additional water-level data had been acquired from wells (expansion wells) in the vicinity of the three original index wells.

Current Updates

Major findings indicate water-level data and interpretation can help in the assessment of the continued viability of the HPA as a source of water for large-scale irrigation and enables important insights concerning the origin of the pumped water and the long-term viability of the aquifer in the vicinity of the index wells. The use of index wells also indicates that the annual water-level measurement network data, in conjunction with reliable water-use data, can be used to evaluate the impact of management decisions on the sub-unit and larger.

Funding

Annual funding varies per year depending on the number of wells being analyzed, well installation and equipment needs. The total over 11 years has been $400,595.00 for an average of $36,418 per year.

Project Manager

Diane Knowles