China’s water resources are spatially and temporally unevenly distributed, with most water available during the summer and in the southern regions. Currently, about 20% of China’s national coal power capacity faces risks of water shortages at times of low river flows, defined as potentially insufficient river levels at times of low flow to meet coal power plants’ water withdrawal demands, from November to June, peaking at 30% in April. Because of the seasonal variation in flow, the exposed capacity is much lower from July to October, at only 10% on average. Spatially, such water shortage risks are concentrated in the north China grid. Over 60% of coal power generation units, whose aggregated capacity is more than 100 GW, are facing water shortage risks in the north in April. Increasing the deployment of air-cooling technology and utilization of alternative water sources (e.g. reclaimed water) are effective options to mitigate such risks. Wetter conditions brought by future climate change may partially alleviate low-flow risks for coal power plants in China, except in the Inland River Basin located in northwest China. However, if the utilization rates of coal power plants are increased, for instance, due to the elevated electricity demands, additional coal power capacity will be exposed to water shortage risks throughout China. Demand management and energy transition in the electric power sector are therefore important countermeasures to be taken.