The Usumacinta watershed, the 6th largest river and second tropical rainforest in Latin America, as well as the cradle of the Mayan civilization. Thanks to the building of five large dams, the important project of Tenosique-Boca del Cerro aims to develop the hydroelectric potential of the mesoamerican region, an area of numerous and contradictory stakes, and high potential of conflict: economically (oil, forest and water ressources), environmentally (patrimony and conservation), as well as a strong political and territorial conflict (out of control border, zapatist guerilla, tense diplomatic relations). As a territorial pivot, this project implies some essential questions, such as the governance of this process in a context of relative democratization, as well as the difficulty of the implementation of Sustainable Development principles. This article gives a geographical approach of these issues, by analysing the territorial logics and strategies witch have been used for 50 years about these potential dams: in 2008, for the fifth time, the mexican government anounced a revival of the project.