Evolution Analysis and Prediction of Peak Value for Residential Water Consumption in Beijing

Residential water demand is the rigid guarantee of water supply system, which related to the macroscopic decision for urban water supply management. Based on the historical data, the evolution of Beijing residential water consumption was analyzed in this study, the results indicate that the key factors affecting residential water demand were the facilities level, water use habits and income. Meanwhile, peak value and time point for water demand were predicted, through quantitative analysis and scenario simulation of the key factors. It is assumed that if household's water conservation maintains the current condition, habits and behaviors regarding water use will reach a relatively stable state, when per capita disposable income increases to 15 000 yuan per month. As consequence, residential water demand will increase to peak value, which about 168 liters per person day. However, under the intervention of water conservation policies, residential water consumption will be 123 liters per person day and 156 liters per person day, while the technical and conscious playing the best roles in water saving. In the scenario that most likely development for water conservation condition, residential water consumption in 2050 will be 143 liters per person day, and water-saving efficiency will be 15%. Based on the analysis of water consumption and water-saving potential, some suggestions were put forward to control the rapid growth of residential water demand in Beijing.