Effects of irrigated parks on outdoor residential water use in a semi-arid city

Abstract

We investigate whether public park amenities act as a substitute for outdoor water use by single-family residential (SFR) households in semi-arid Tucson, AZ, USA. Specifically we account for the effects of a park's proximity, size, and greenness (measured by NDVI), as well as the presence of a public swimming pool. SFR households with and without home pools are analyzed separately. We control for SFR property attributes, including house size, age, yard size and property NDVI. Results suggest that SFR outdoor water use is influenced by the conditions of all parks within an 8km (5mile) street distance. We also find significant differences between the “with” and “without” home pool groups. Households with pools used more outdoor water per square meter of house, per year of house age and per unit of NDVI. Households without pools appeared to reduce outdoor use in response to nearby small parks and increased park NDVI. “With pool” households had the opposite response: they appeared to increase outdoor water use in response to these variables. However, “with pool” households did reduce their outdoor water use in response to nearby public pools. Medium and large parks were associated with increased outdoor water use for both groups. We conclude that public green space and pools can substitute for private versions of these amenities, and if well designed, can contribute to water demand management and urban sustainability. This may be an avenue for addressing water supply shortages in semi-arid cities and other areas where populations are growing but water supplies are finite.