In the development of this document was identified water consumption Bogota, Sao Paulo and Mexico City, where they find the sectors with higher water consumption of each of these cities, the same way they show what measures, projects or laws that have been willing to take to be a rational use of this resource. On the other hand, we show that using these cities give their wastewater after being treated. Subsequently perform two comparisons one in Bogota and Sao Paulo, and the other between Bogota and Mexico City, where they observe the measures that each of these cities has taken to reduce water consumption per capita.