ABSTRACT
The availability of enough and suitable resources to satisfy the different kinds of water demands in the urban context represents the main basis of supply services. The maintenance of the balance between availability and demand is subject to threats of different nature, and when this balance is broken it has a major impact on and generates costs to citizens, entities and even those responsible for the supply. The break-up of this balance represents one of the main risks which the urban water service must cope with. The problem has not yet been set or solved in a homogeneous way internationally, not even in contexts involving situations of hydric stress. The solutions posited in this paper focus on methodological and operational aspects. From the methodological point of view, a clear difference of setting has been established, with a clear separation between those related to the failure or normal situation and indicators and corresponding conventions to be used in planning, operating and solving contingencies. As for the operational aspects, a division into stages or phases is set with their corresponding effect and cost distribution among the different parties involved. In both approaches, considering risk as a main factor in analysis and decision making is the main pillar for the efficient management of resources and commitments with society and the environment.
