Proposal of an index to evaluate the ‘dewaterization’ of the urban water cycle and a practical application

Abstract

Analyses of the relationship between water and energy do not account for the fact that the energy used in the urban water cycle is a consumer of water. To ensure the efficient use of water resources, the operator must know the raw water use associated with the energy input of the urban water infrastructure. The main contribution of this research is the proposal of an index that measures how much raw water is consumed by the energy used to produce 1 cubic m of water. The resulting index is a decision-making tool that enables the sustainable use of water resources. This article first explains the index, which is called the Water Footprint of the Urban Water Cycle. It then provides examples of how to apply the proposed method; among other applications, it can be used to establish a classification of energy sources based on their relative consumption of raw water, according to the electricity generation mix in each service area. The proposed method is useful for operators, policymakers and other stakeholders, enabling them to make decisions that contribute to the 'dewaterization' of the urban water cycle.