La demande d'eau potable à La Réunion : Estimation à partir de données d'enquête

In this paper, we estimate a residential water demand function for the Reunion island, a French overseas territory which experiences, despite its tropical climate, a lot of stress on this resource. We develop specifications of linear and non linear expenditure systems, taking into account the increasing block rate schedule current in the island. This modelling allows differentiating within the total residential water consumption a component independent of prices and household income, called committed consumption, and a variable part which can be influenced by a relevant water pricing policy. Using survey data collected on a sample of households, our empirical results reveal the importance of committed consumption and of outdoor uses of water. The expected drops in water consumption generated by socially acceptable rate changes appear therefore limited and it is advisable to complement pricing policies with other measures, such as information campaigns focusing the outdoor uses of water