The San Joaquin Valley of California, despite supplying a significant percentage of the country’s food, is nevertheless a dry, arid place. Fresno, at the heart of the valley, receives just over 10 inches of rain a year on average, according to the National Weather Service, and sometimes as little as 3. And yet, until the late 19th century, the San Joaquin Valley held a lake more than 100 miles long and over 30 miles wide. Tulare Lake “was the largest body of fresh water west of the Mississippi River. It’s really difficult to imagine that now,” says Vivian Underhill, formerly a postdoctoral research fellow at Northeastern University with the Social Science and Environmental Health Research Institute. In research conducted while at Northeastern, Underhill describes the lake’s recent, surprising return as a result of 2023’s atmospheric rivers over California, and the effects the lake’s return has had on indigenous communities, wildlife and agricultural workers in the San Joaquin Valley.