Aerial photo taken on May 22, 2021 shows the Shahe aqueduct, key project of the middle route of China's South-to-North Water Diversion Project. As of 8 a.m. Monday, the middle route of China's South-to-North Water Diversion Project has transferred more than 40 billion cubic meters of water to the country's arid north, official data showed. (Xinhua/Liu Shiping)
