How much does water consumption drop when each household takes charge of its own consumption? the case of the city of Seville

Abstract

Making individuals take charge of their own domestic water consumption is one of the measures used to reduce the growing demand for this resource and to achieve sustainable consumption compatible with the goal of equity. The use of individual meters instead of communal meters and fixing tariffs by inhabitant rather than by household are two measures aimed at achieving these objectives. This article assesses the measures put in place in the Seville metropolitan area during the last 20 years with an unobserved component model set up in a statespace framework estimated using maximum likelihood. Water consumption elasticity to individual meters has changed from –0.307 to –1.317 with the introduction of per inhabitant tariffs, which demonstrates that there are watersaving synergies when the two measures are implemented together. The reductions in water consumption achieved with these measures are also longer lasting than the changes in consumption habits during the frequent droughts in Seville.