Abstract: The watersheds of the Tacaná volcano, which stands at an altitude of 4,093 m, cover a transboundary area of 3,170 km² right in the middle of the border area of the Department of San Marcos, Guatemala and the State of Chiapas, Mexico. This area comprises the Coatán, Suchiate, Cosalapa and Cahoacán rivers. The Coatán and Suchiate watersheds are shared by Guatemala and Mexico. These watersheds are of great strategic importance for both countries as they supply water to a large number of residents in the cities downstream, and are the main source of irrigation for agriculture. In the lower reaches, fishing is an important source of income.

Authors: Stefano Barchiesi, Rocío Córdoba