Water balance modelling in Glasgow and Beijing

Abstract

This paper compares the overall water balance of two contrasting cities. Glasgow and Beijing have different soil and climate characteristics and also different water resource policies. Glasgow uses remote rural surface water catchments while Beijing relies more on groundwater. Both cities are introducing sustainable water management policies in various forms. In the case of Glasgow the policies are more directed to flood alleviation while in Beijing one of the drivers is groundwater recharge. The overall water balance of the two cities is modelled using an integrated three-stage numerical tank model. This model represents the processes of infiltration, evaporation, runoff and storage for both paved and unpaved surfaces and indicates the overall water balance over a typical year. The results of the modelling highlight the importance of evaporation in the overall urban water balance and the potential for using stormwater runoff to reduce water demand or to recharge groundwater.