In California’s southern San Joaquin Valley, a vast expanse of farmland stretches across what was once the largest freshwater lake west of the Mississippi River. This is the former bed of Tulare Lake, a massive body of water that once covered up to 790 square miles during seasonal floods.Tulare Lake was not only immense in size but vital to Indigenous communities, wildlife, and the regional hydrology.
Yet by the early 20th century, this enormous lake had vanished. Tulare Lake was not drained by drought or natural disaster, but by human intervention. In a span of decades, agricultural development, dam building, and water diversions transformed it from a thriving aquatic ecosystem into an engineered landscape of irrigation canals, cotton fields, and livestock feedlots.
The story of Tulare Lake is one of both environmental transformation and consequence. It’s a case study in how humans can reshape geography, alter ecosystems, and set into motion long-term changes still felt today.
A Shifting Inland Sea
Tulare Lake once sat at the lowest point of the Tulare Basin, a closed hydrological system with no natural outlet to the ocean. Water from the Kings, Kaweah, Tule, and Kern rivers flowed into the basin from the nearby Sierra Nevada Mountains. During years of heavy snowmelt or rainfall, the lake would swell dramatically, expanding far beyond its usual bounds and submerging vast portions of what is now Kings and Tulare Counties…