Water demand has a continued growth, but not its availability. To achieve a regional balanced development of the activities that demand water as a basic input, it is necessary that water demands are in agreement with water availability. To balance both components is not always an easy task, because of the multiple water uses (agriculture, domestic use, aquaculture, industry, energy generation, etc.), and because frequently the users do not have a registration or official assignment with the correct physical location and the volumes to use; on the other hand, the offer is also frequently only supposed, since measurements are not made, neither controlled due to, among other factors, the lack of inadequacy of the hydrometric network, the lack of economic resources to assist this activity, and the rural and isolated control points, etc.