The Rio Grande/Rio Bravo flow rate from El Paso/Ciudad Juarez to Fort Quitman/Cajoncitos has changed since the 19th century due to agriculture irrigation on both sides of the border. The river has been modified by agricultural infrastructure, as well as water quality degradation along the border due to wastewater discharges. Aquifers underlying the Rio Grande/Rio Bravo are being exhausted in the El Paso/Ciudad Juarez area as well. For these reasons, the ecosystems have been altered drastically. The vegetable and animal life that depend on the river and its riparian areas have been affected. The river water is legally tied to different users of this vital liquid, but ecosystem, as a user, is not included or considered in the water planning and management. Officially, there is no water allocation to maintain the ecosystems water needs downstream Ciudad Juarez-El Paso. The present condition of the Rio Grande/Rio Bravo is considered in the list “of the most threatened rivers” by conservation organizations, however, in México it has not been analyzed sufficiently, from an environmental and ecological point of view. The main purpose of this work is to establish the basis for the ecological restoration of the Rio Grande/Rio Bravo in El Paso/Ciudad Juarez-Fort Quitman/Cajoncitos section. The methodology consists of the revision and analysis of the historic hydrological data and the water quality in this region to define a minimum ecological flow rate to the river, supported on hydrological studies; in addition, an inventory of flora and fauna will be made through an exhaustive bibliographical revision, interviews with officials of the Mexican government, representatives of water users of the Irrigation District 009, and people from the Juarez Valley, and field visits. In order to elaborate the scenarios of water reallocation in the region, the Rules of Water Use of International Rivers from The International Association of Law (Rules of Helsinki) of the Conference of Berlin, 2004, is going to be taken, as well as the Project of Modernization and Technical Improvement of Irrigation Districts of the Conchos River. The economic contexts of development of both cities will be studied. Scenarios for water reallocation in the region based on minimum flow maintenance will be formulated to permit the return or repopulation of native species while maintaining historical beneficial uses.