In the Salt Lake basin of Turkey, chemical composition of inflow surface waters defines a continuous trend from Ca-HCO3-rich spring waters to Na-SO4-Cl-rich brines. Considerable compositional variation exists among the surface waters. Water-rock interaction governs compositional variations in springs, streams and rivers, and is enhanced by evaporation and precipitation of calcite and protodolomite. Solute concentrations of the streams and the rivers are partially controlled by the mineralogy of the playa deposits. The concentration increase from inflow surface waters to a Na-Cl-type lake surface brine is not accessible to direct observation. The principal cause of the evolution from SO4-rich brine to Cl-rich brine in the lake is interpreted as the recycling of solutes through the differential dissolution of efflorescent crusts.