Tonto River
The Tonto River is a river of Oaxaca, Mexico that flows from the mountains of Zongolica. It is dammed by the Miguel [Alemán Dam] near the town of Temascal or [Nuevo Soyaltepec], forming the Miguel Alemán Lake.
Below the dam, the river flows southeast past San [Juan Bautista Tuxtepec], where it joins the Santo Domingo River to form the Papaloapan River.