NCW Libraries

Soap Lake is located in eastern Washington at the southern end of the Lower Grand Coulee. Carved by the erosive forces of cataclysmic floods, the lake paints a serene portrait across a landscape framed with rugged basalt cliffs and talus slopes. After thousands of years, groundwater leaching through hundreds of feet of basalt created the lake, which has a high concentration of sulfate, carbonate, bicarbonate, sodium, and chloride and a pH at or close...