Cooling effects of pavement-watering applied to two innovative pavements: Case study from the LIFE “Cool and low noise Asphalt” project

Abstract

In the context of its adaptation to climate change, the city of Paris has been experimenting pavement-watering since 2013. More recently, in the context of the LIFE “Cool & Low Noise Asphalt” project, innovative pavements were studied in combination with pavement-watering from summer 2019 to 2021. In this paper, the analysis focuses on the performance of pavement-watering conducted on two innovative and one standard pavements deployed rues Frémicourt and Lecourbe. Microclimatic conditions were monitored using fixed weather stations at each location measuring air temperature and humidity, wind speed and black globe temperature, used together to calculate mean radiant temperature. Pavement-watering impacts on Urban Heat Island (UHI) intensity and pedestrian heat stress were determined using air temperature and the Universal Thermal Climate Index (UTCI), respectively. For each pavement, statistically significant effects were observed. Results show maximum reductions between −0.7 to −0.9 °C of air temperature and between −1.5 and −2.2 °C UTCI-equivalent temperature with effects lasting from 3.2 to 7.1 h during the day. No statistically significant effects are observed on UHI intensity at either site. Additional experiments will allow the study of dry pavement performance and the optimization of watering.