|Mouth||Río Grande de Matagalpa|
|Length||180 kilometres (110 mi)|
The river, a left tributary of the Río Grande de Matagalpa, is located in the Jinotega and Matagalpa Departments, Región Autónoma del Atlántico Norte, and Región Autónoma del Atlántico Sur. The source of the Tuma River is located in Jinotega Department, about 250 kilometers northeast of the capital, Managua. The river flows in the eastern direction, crosses into Matagalpa Department, in the lower course forms the border between Matagalpa Department and Región Autónoma del Atlántico Norte, and between Región Autónoma del Atlántico Norte and Región Autónoma del Atlántico Sur where it joins Río Grande de Matagalpa.
In 1964, President Luis Somoza Debayle decided to dam the river to form Nicaragua's first man-made lake, Apanás Lake, which provides power for the 50-megawatt Centroamérica hydroelectric plant in the country's Central Highlands. It is also an important recreational area, as the river and lake provide a good deal of tourism for Jinotega department.
- "Libra de la Defensa Nacional de Nicaragua" (in Spanish). Government of Nicaragua. p. 30. Retrieved 25 May 2012.
- Hugh Chisholm (1911). The encyclopædia britannica: a dictionary of arts, sciences, literature and general information. At the University press. pp. 643–. Retrieved 23 February 2011.
- About the Area. Selva Negra. Retrieved on 2011-02-23.
- Guide to Apanás Lake at Worldsaurus.com