An agent-based model for the evaluation of the expected impact of water demand management policies

In this paper we describe an agent-based model that simulates the water consumption behaviour of households exposed to different stimuli and incentives promoting water efficiency and a more sustainable consumption of water. The model includes two main types of agents. The first type represents the water utility, while the second represents the households of the considered urban region. The model of the water utility receives from every household model their daily level of water consumption which is computed on the basis of the household features and the water price, but it also considers how the interaction among the households affects water use, under the assumption that users are stimulated to save more water if similar households in their network of social relationship have a lower average consumption. In the model two processes are modelled: first the diffusion of an app that allows users to be informed about their hourly/daily water consumption and relate their consumption level to the one of similar users, and secondly the process of behavioral change experienced by households exposed to the information provided by the app. The model thus allows to explore how different adoption levels of the app and different sensitivities to the social norm can impact collective behaviour. This is achieved by introducing two information diffusion sub-models that describe the interaction among users and a mechanism to capture also the effect of price incentives. The agent-based model has been implemented using the AnyLogic simulation platform. The model has been applied to data collected in a real world case of 250 households in the Locarno district in Southern Switzerland and validation results are discussed.