The Tuolumne River (/tuːˈɒləmiː/; Yokutsan: Tawalimnu) is a California river that flows for 149 miles (240 km) from the central Sierra Nevada to the San Joaquin River in the Central Valley. The river is formed by the confluence of the Lyell and Dana Forks in Yosemite National Park; from there it flows generally westward through the foothills of the Sierra Nevada where it is dammed by the New Don Pedro Dam, through farmland in the Central Valley, to its mouth near Modesto.