Tulare Lake, intermittent lake, in the Central Valley, central Calif. The Kings, Kaweah, and Kern rivers at one time flowed into the lake, but their waters have been diverted for irrigation. The land in the lake's basin has a high salt content. In dry seasons, Tulare Lake is almost without water. Visited by the Spanish in 1772, the lake then was c.50 mi (80 km) long and c.35 mi (60 km) wide.