The Nishitakase-gawa River takes the water from the Katsura-gawa River in Saga Tenryu-ji Suminokura-cho, Ukyo Ward, Kyoto City (several hundred meters to the east of Togetsu-kyo Bridge) and flows to the Kamo-gawa River (of the Yodo-gawa River system) in Kamimukaijima-cho, Shimotoba, Fushimi Ward, Kyoto City.
京都市右京区嵯峨天竜寺角倉町(渡月橋の東、数百メートル)の桂川から取水し、京都市伏見区下鳥羽上向島町で鴨川(淀川水系)に注ぐ。