The proposed Towanda Lake would be formed by the impoundment of the Whitewater River near Towanda, Kansas. Project purposes would include flood control, water supply, and general recreation. The purpose of this study was to investigate possible water quality problems that may affect the realization of project benefits particularly the effects of total dissolved solids (TDS), chloride, and sulfate concentrations on water supply suitability. Because of the high concentrations of these parameters, possible treatment processes were to be evaluated for alleviation of potential water supply problems.