Tulare Lake has re-formed across more than 100,000 acres in California's Central Valley in 2023, reoccupying a basin that had remained dry for over 130 years after being drained for agriculture. Once the largest freshwater lake west of the Mississippi River, the lake's return was triggered by record snowpack in the Sierra Nevada and the overflow of the Kings, Kaweah, Tule, and White rivers, overwhelming existing flood control infrastructure.

The California Department of Water Resources confirmed that the Tulare Lake basin, though long considered hydrologically extinct due to water diversions and land reclamation, is a natural terminal sink that reactivated when atmospheric rivers delivered more than 12 major storms through winter and spring. The resulting snowpack reached nearly 300% of average in parts of the southern Sierra, and its rapid melt exceeded canal and reservoir capacities, redirecting floodwaters into the historic lakebed.

The refilling has caused extensive damage to farmland and rural infrastructure in the region, with state and federal agencies coordinating emergency flood response and evacuations. At the same time, the lake has rapidly restored wetland ecosystems, attracting tens of thousands of migratory birds, including American Avocets and Black-necked Stilts, to newly inundated areas along the Pacific Flyway.

For the Tachi Yokut Tribe, the lake's return revives Pa'ashi, a site central to cultural and subsistence practices for generations before its diversion. Tribal members have resumed traditional ceremonies on the water for the first time in over a century, describing the event as a reaffirmation of ancestral connection to the land.

State water officials are assessing long-term flood risks and ecological impacts, as residual water is expected to persist into 2024. The Central Valley Flood Protection Board will review levee performance and basin management strategies at its next quarterly meeting in September.