Dakota Home Report Archive Report Start

Kansas Geological Survey, Open-File Rept. 96-1a
Proposed Management Areas--Page 14 of 16

Management Area V

In Management Area V the thickness of the Upper Cretaceous aquitard is generally greater than 400 ft along its south and east boundaries, and along its northern boundary with Management Area VI the aquitard thickness ranges from approximately 600 ft in southeastern Rooks County to 2,000 ft along the Kansas-Colorado border in Wallace County. The boundary between Management Area VA and Management Area VB is the approximate location of the 1,500 mg/l total dissolved solids isocon n the upper Dakota aquifer (Figure 4). Depths to the top of the Dakota are generally less than 1,000 ft in area VA. Belitz and Bredehoeft (1988) and Macfarlane (1993) estimated the hydraulic conductivity of the aquitard in this management area to be approximately 10-7 ft/day. Consequently, recharge from overlying sources is negligible. Regional recharge areas in southeastern Colorado and discharge areas in central Kansas are sufficiently far away that pumping will not induce additional recharge or reduce discharge during the 20 yr planning horizon.

The density of development in this region is currently very low. At present the spacing between pumping centers (wellfields) that withdraw water at higher rates is greater than 20 mi. Well spacing should be the greatest in this management area to minimize the likelihood of water-rights impairment. Modeling studies reported in Smith (1995) suggest that a well spacing of 20 mi and coupled with restrictions on rates of withdrawal are appropriate to minimize the possibility of impairment. In area VA, the water quality is acceptable for most uses. In area VB ground water in the Dakota is marginally usable but would require some level of advanced treatment to remove dissolved solids. In general, the farther to the north and east in these areas, the greater the increase in salinity with depth.

Previous page--Management Area IV || Next page--Management Area VI
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