Saline water discharges from the alluvial aquifer into the Smoky Hill and Solomon Rivers between New Cambria and Sand Springs, Kansas. During relatively stable base flow in 1976-77, the discharge was about 32 cubic feet per second. Chloride concentrations at base flow increased about 800 milligrams per liter in the Smoky Hill River and 550 milligrams per liter in the Solomon River.
The source of the saline water is the underlying Wellington aquifer, a zone of dissolution, subsidence, and collapse along the eastern margin of the Wellington Formation. Locally, brine from the aquifer moves upward through collapse structures in the confining layer at the base of the alluvium. The brine discharge ranges from 0.3 to 0.8 cubic foot per second, and the chloride load ranges from 150 to 370 tons per day.
Results from a mathematical model of the fl ow system indicated that recharge from periodic flooding, as in 1973, was sufficient to reverse the normal (197677) hydraulic gradient between aquifers. Although brine discharge was temporarily reduced, saline-water discharge to the rivers increased.
The discharge of brine could be intercepted by pumping wells completed in the Wellington aquifer to lower the potentiometric head and reduce upward flow. The intercepted brine could be discharged into formations underlying the area at depth or piped to a storage reservoir from which the brine would be evaporated or released to the rivers during peak flows. Also, the freshwater in upstream base flow could be diverted by canal, and the saline-water discharge could be retained by low-head dams in the river channel for release during peak flows.
