The impact of turf removal on residential water use in a Mediterranean-climate metropolis: is lawn replacement decoupling water use from historical trends?

Abstract

Urban water supply reliability is a pressing challenge facing cities worldwide, and understanding the effectiveness of water conservation measures has become crucial. In this study, the impact of turf removal on residential water use in a Mediterranean-climate metropolis facing water scarcity was quantified, based on a data-driven empirical approach. A method using Sentinel-2 imagery was implemented to assess turf cover evolution from 2019 to 2023. Combined with household water use data, the impact of turf removal was analyzed at local and city scales. Residential water use savings at an average rate of 6.5 mm/day are demonstrated. The savings have been pivotal in decoupling water use from historical trends. The findings suggest that turf removal may account for 60% of the decoupling, equivalent to the entire city-demand stagnation. The results are of interest for sustainable urban water use public policy design and the economic evaluation of water conservation measures.