Household vulnerability to intermittent water supply systems

Intermittent supply in water distribution systems occurs when the water service is available for a limited period of time, producing adverse effects on the water supply network and users of the system, in particular domestic users, whose demand is not flexible and the adaptive capacity is limited. This paper proposed a simplified set of indicators to identify different levels of vulnerability to water shortages to which an urban population is subject, in a situation of intermittent water supply. The indicators can be obtained from census data, topological, topographic, and hydraulic information from the supply system and from cadastral surveys or remote sensing of the locality, and can be processed in geographic information systems (GIS). This article presented the formulation of the indicators and their application to the Campina Grande system, Paraiba, Brazil, based on available surveys on users in intermittent supply situations. The results allow the identification of areas whose users may be potentially most affected by intermittent supply and the recommendation of mitigating measures to reduce their vulnerability.