For another bias economic science classifies the necessities of diverse forms and categories. One of the forms to classify is for the primary and consequently vital priority. For GALVEZ (2004, P. 48) ' ' primary necessities are the ones that say respect to the satisfaction of the vital minimum that assures the maintenance of the life humana' '. The water is primary, vital, collective and until then, irreplaceable necessity for the maintenance of the life. However, this affirmation alone is valid for a consumption that is restricted to the basic necessities, wants to say: water to drink, to cook, asseio and activities of this sort. In such a way, the subjective necessity or &#039 can also exist; ' created artificialmente' ' for the economic system, where the consumption reaches high levels of wastefulness and not with priority applications to the maintenance of the life.

TUNDISI (2003, P. 248) affirms that ' ' the growth and economic development, allies to the diversification of the society, had resulted in uses multiple and varied of the resources hdricos' '. Thus, to understand this process of scarcity it has that to analyze itself as the population growth, the urbanization and the income unchain the activity human being and as this affects the availability of the water. Quality water and degradation of and amount of the hdricos resources to last the current trends of growth of the demand of, such resources will become scarcer. ' ' The still available water in the planet is converted into the blue gold of century XXI because, in the current model of consumption, this element already is not enough. She is necessary to treat it as merchandise, regulating its uso' ' (URBAN 2004, p.107). This dialectic goes beyond a simple joint of scales; it has its origin in the proper concretude of the historical process. Therefore exactly in periods of orders, integration, generalization and joint, mainly through the State in history most recent, identify moments of disintegration, spalling and clutter that are part of the same historical process.