Putah Creek pours down the eastern slope of Cobb Mountain, one of the hundreds of foothill streams that support California's unique flora and fauna. Thirty miles from its headwaters, it pools behind Monticello Dam to form Lake Berryessa, the eighth largest reservoir in the state. Past the dam's floodgates, it meanders another thirty miles before emptying into the Yolo Bypass.

In 1989, Lower Putah Creek ran dry.