Improvements in the water usage efficiency of the Mexican Valley

Mexico City Metropolitan Area is located at an altitude of 2300 meters above sea level has a surface of 5000 Km² and a population of 19.1 million whose water supply and usage represent a serious problem of sustainability and development. The efficient supply and usage of water resources is crucial for a city characterized by industrial centers, a wide range of economic activities and densely populated urban areas. In a systemic study of water sustainability, in progress at Instituto Politécnico Nacional, there were identified six sets of problem areas: 1) General issues, 2) Sources 3) Uses 4) Distribution, 5) Industry and 6) Management. In this paper it is presented a set of solutions to the second and third partial problems: how to improve the water supply and usage of water under a sustainable development of Mexico City Metropolitan Area. First of all, there are defined several relevant subsystems, relationships and specific problems. Then it is defined a structure to analyze systemically this part of the total problem and finally some solutions are proposed in the short, medium and long term, for example avoiding the unsustainable uses of ground water sources.