Like the lake above, water flowing into Great Salt Lake comes from two main sources: precipitation and inflow from rivers. River water carries small amounts of dissolved minerals, which have become concentrated over thousands of years, making the lake salty and mineral-rich.
Because this lake, like Great Salt Lake, sits at the bottom of a closed basin, no rivers flow out of it. The only way water can leave is through evaporation. When water evaporates, everything dissolved in it stays behind-including salt, minerals, and pollutants.