The management of the water is equivalent to the management of conflicts between human beings and between these ones and the environment. A system of management of the water is created to avoid these conflicts, to prevent them and to solve them. The human being must learn to live with these conflicts and to face them adequately, knowing besides the fact that the relative scarcity of water will increase constantly with the time, product of the economic growth, social demands and climatic changes. The competition between users will be more and more drastic and merciless for what it is needed to have laws and institutions to manage adequately the system.