Urban household water usage in adaptation to climate change: Evidence from China

While it has been concluded that climate change poses a significant threat to worldwide supply of freshwater resources, it is unclear if and how demand for water would also be affected. To fill this knowledge gap, we leverage on ‘big data’ collected using smart water meters from over 40,000 Chinese urban households, spanning nine years and ten provinces to examine the relationship between daily household water usage and climate variability. At the baseline, we find that municipal water is not only a coping mechanism for heat, but its usage is accelerated during heatwave events. Heterogeneity analyses reveal that households from lower-valued properties are more likely to substitute water for electricity to counter heat. Importantly, we find evidence of adaptation behaviors where over time, households are using increasingly more water to cope with high-temperature days. In all, after feeding our results into climate projection models, it is estimated that household water usage will increase by around 7–44% in the long-term (2080–2099) under emissions scenarios of SSP245 and SSP370. Our findings are especially relevant for water-scarce countries such as China as well as developing countries where water is a cheaper and more accessible resource to cope with heat.