The Seta River (also redundantly Setagawa River Japanese: 瀬田川 Seta-gawa) is the principal river in the Osaka Prefecture of Honshu island, Japan. The source of the river is Lake Biwa in the Shiga Prefecture to the north. The Yodo river properly begins at the confluence of the Katsura , Uji and Kizu rivers. At the city of Osaka, the Yodo drains into Osaka Bay.