Dakota Home Report Archive Report Start

Kansas Geological Survey, Open-File Rept. 91-1
Annual Report, FY 90--Page 2 of 9


The Dakota aquifer system is an integral part of the water-resources planning for central and western Kansas. This aquifer system underlies approximately the western half of Kansas, adjacent portions of Colorado and Nebraska, and much of the rest of the midcontinent region of North America (Figure 1). A lack of water due to local depletion of shallower freshwater aquifers in central and western parts of Kansas will create a demand for water supplies from the underlying Dakota aquifer in the future. In addition those areas of the Dakota aquifer currently undergoing development are managed with little or no technical guidance for policy decisions because of a lack of data. In central Kansas oil-brine disposal in shallow zones beneath the Dakota aquifer may impact water quality in the Dakota, overlying aquifers, and surface waters by increasing the potential for upward migration of natural and disposed brines. At present insufficient data on water quality and availability preclude a thorough evaluation of the aquifer's ability to support the long-term development that will occur as shallower sources of water are depleted or to assess the effects of shallow oil-brine disposal practices.

Figure 1. Extent of the Dakota aquifer in Kansas.

In recognition of the need for an integrated program of research, the Kansas Geological Survey has been carrying out and coordinating a long-term multi-agency program to assess the water-resources potential of this aquifer since FY89. Work completed by the end of the program's first year (FY89) included the initial stages of data-base development and regional-scale investigations of the aquifer framework, and its properties, and water quality, and use, and research on the energy used to pump water from large-capacity wells. The results of the FY89 project are discussed in detail in the FY89 annual report. On the basis of the work completed during FY89, several water quantity-quality problems associated with long-term development were identified. These problem areas relate to (1) water availability, (2) sources of recharge and their effects on water quality in the Dakota aquifer, (3) the impact of withdrawals of water from the Ogallala and Dakota aquifer in southwestern Kansas on future water-supply availability, (4) the effect of shallow disposal of produced oil brines in the Permian on the Dakota aquifer in central Kansas, (5) the definition of usable zones in the Dakota aquifer, and (6) the effect of saltwater discharge from the Dakota aquifer on water quality in central Kansas stream-aquifer systems. Additionally, work was directed toward further definition of the long-term research plan directions for the Dakota aquifer program. As a result, the program is concentrating on three sub-areas where the aquifer is presently under development in southwest and central Kansas during FY90-92. Emphasis will then shift to the deeper subsurface of western Kansas (Figure 2) and assessment of water-resources management options in the area of the Dakota aquifer currently under development in FY93.

For FY90-93 the overall objective of the Dakota aquifer program is to characterize subregionally the water resources potential of the Dakota aquifer where it is shallowest and is presently undergoing development (Figure 2). In the areas of more intensive use, the aquifer supplies water for irrigation, public water supply, and industry. Three major subareas of investigation have been defined that coincide with the areas under development. Insufficient up-to-date information is available in the these three main sub-areas of investigation to assess the water-resources potential of the aquifer. In FY90 the KGS and the USGS collected new detailed geologic, hydrologic, and water-quality information that previously has been nonexistent or has been needed to update existing data bases in order to characterize or re-evaluate ground-water flow patterns and water chemistry.

Figure 2. Extent of the Dakota aquifer in Kansas and subareas of investigation.

The following is an annual report of the Dakota aquifer program that summarizes the activities and results of the program during FY90. Details concerning specific areas of research in the program completed during FY90 will be reported as stand-alone chapters. Technical papers from the Dakota aquifer program will continue to be reported in the Kansas Geological Survey's Open-File Report series. Each annual report will be given a number, such as 91-1, and each chapter will be given the same number followed by a letter of the alphabet that corresponds to its position in the sequence of reports for that year, such as 91-1a.

Previous page--Start and Executive Summary || Next page--Regional Setting
Start of this report || Table of Contents

Kansas Geological Survey, Dakota Aquifer Program
Original report available from the Kansas Geological Survey.
Electronic version placed online July 1996
Scientific comments to P. Allen Macfarlane
Web comments to webadmin@kgs.ku.edu