Volume driven analysis for house level water supply assessment in an intermittent water supply system

Abstract

ABSTRACT Intermittent water supply (IWS) system delivers the drinking water for a short duration of a day. Customers’ satisfaction with such a system highly depends on the volume of water delivered at each house service connection rather than the pressure-dependent flow rate. In most of the systems, the supply is made until emptying of the source storage reservoir or tank happens. The advantaged consumers (who belong to the high-pressure zone) receive water quicker than the disadvantaged consumers. As the IWS has trusted with the volume of water delivered, volume-driven analysis (VDA) is required to understand the supply rate at demand nodes and the actual duration of supply to the consumers located across the network. Supply to each house service connection (HSC) depends on the availability of static pressure at the ferrule points in the distribution main. The aggregated volume of water that can be delivered by the node corresponding to the available pressure requires an equivalent arrangement that represents house service connections (HSCs) in the modeling. In the present work, a modified method of volume-driven analysis is presented to simulate the aggregated flow from the HSCs at each node and to evaluate the actual volume of water delivered within the supply duration. The application of the method is illustrated through a hypothetical rural water supply network. The volume of water that can be received by the group of houses and its duration of supply to fulfill the demanded volume can be obtained from the proposed analysis and also it is shown how the uncontrolled withdrawal of water affects the disadvantaged consumers in the water supply system.