How to “drink”, “store” and “replenish” the river water coming from the south through the South-to-North Water Diversion Project?

2024 marks the 10th anniversary of the completion of the middle route of the South-to-North Water Diversion Project. The reporter learned from the China South-to-North Water Diversion Group that as of 15:20 on the 12th, the first phase of the South-to-North Water Diversion Project had delivered 10 billion cubic meters of water to Beijing, directly benefiting more than 16 million people.

The latest data showed that on the afternoon of the 12th, the first phase of the South-to-North Water Diversion Project has transferred a total of 10 billion cubic meters of water to Beijing since it was fully put into operation in December 2014. The water supply safety factor of the central urban area has been increased from 1.0 to 1.3, and the water quality has always been stable at Class II and above of the surface water environmental quality standard.

Wei Yaoguo, deputy general manager of China South-to-North Water Diversion Group Middle Route Co., Ltd.: More than 70% of Beijing's urban water supply is water from the South-to-North Water Diversion Project. The annual per capita water resources in Beijing have increased from 100 cubic meters to about 150 cubic meters, which has greatly alleviated the capital's water shortage and effectively improved the city's water supply security. It also provides water source support for key areas such as the city's sub-center and Daxing International Airport.

At present, Beijing has gradually built a water resource guarantee system that is compatible with its position as a capital. Recently, the Changping New Town Surface Water Plant, the first water plant in Changping District, Beijing that uses the South-to-North Water Diversion Project as its water source, completed commissioning and operation. After the water is officially turned on, the coverage area will reach 600,000 people. So far, Beijing has 15 water plants that receive water from the south.

Li Shuying, a resident of the Beijing Fengtai Hexi No. 3 Water Plant, said: "We used to boil water in a kettle and then let it settle for more than ten minutes before filling the thermos. However, there was a lot of limescale in the kettle. Now, the water quality is much better than before due to the South-to-North Water Diversion Project, and the limescale has been greatly reduced."

At present, Beijing's maximum water supply capacity is basically stable at about 1.3 times the average water demand, and the daily processing capacity of water from the south has reached 4.7 million cubic meters. Based on the sufficient guarantee of water from the south, Beijing has made great efforts in water production and distribution, so that more citizens can drink safe and high-quality municipal tap water.

In addition, the southern water has also injected "lifeblood" into urban development. Beijing's groundwater level has risen significantly for many consecutive years, and many rivers have regained vitality.

Zhao Hongyan, Chief of the Groundwater Monitoring and Evaluation Section of Beijing Hydrological Station: From 1999 to 2007, Beijing experienced a nine-year drought. During this period, the groundwater level in Beijing showed a downward trend year by year. After the South-to-North Water Diversion Project was introduced into Beijing, we increased the pressure on groundwater extraction and carried out ecological water replenishment in a timely manner, which greatly conserved groundwater. Especially since 2015, the groundwater depth has risen from 25.75 meters to 14.74 meters in 2023.

The arrival of "water from the south" has also helped improve Beijing's water ecology. Through multi-source cross-basin ecological water replenishment, Beijing's five major rivers have all become "flowing rivers" again after 26 years, and have flowed into the sea for three consecutive years. The length of rivers with water has increased by 464 kilometers compared to ten years ago.

Li Shu, Chief of the Dispatching Management Section of Beijing Water Resources Dispatching Management Center: We follow the principle of using the best water for the best use and using it according to its quality, and the principle of using it in the order of saving, drinking, storing and replenishing, giving priority to making full use of the water from the South-to-North Water Diversion Project. The ecological water that originally occupied the river has been returned to the river channel, and the ecological environment and biodiversity of rivers and lakes have also been greatly enriched and improved.

A clear river flows for 3,000 miles, nourishing the people along the coast. The South-to-North Water Diversion Project is a national strategic project, divided into three routes: east, middle, and west. Among them, the starting point of the middle route project is located at the Danjiangkou Reservoir in the middle and upper reaches of the Han River. Let's learn about this water transfer lifeline together↓↓↓

The middle route of the South-to-North Water Diversion Project diverts water from the Danjiangkou Reservoir, which spans Hubei and Henan provinces, in the middle and upper reaches of the Han River, the largest tributary of the Yangtze River. The total length of the water transmission line is 1,432 kilometers. Since the gates at the head of the canal were opened to release water on December 12, 2014, the Danjiang River water has been flowing northward and poured into Beijing's Tuancheng Lake 15 days later, delivering nearly 65 billion cubic meters of water to 26 cities along the Beijing-Tianjin-Hebei-Henan route, equivalent to more than 4,400 West Lakes, and directly benefiting more than 100 million people.

The water from the Yangtze River flows out of the Danjiangkou Reservoir and flows northward. The Yellow River becomes a natural barrier that prevents water from flowing northward. In order to solve this problem, the "Chuanhuang Project" was born. "Chuanhuang" means "crossing the Yellow River". The complex geological conditions under the Yellow River bed have destined the Chuanhuang Tunnel to be different from ordinary traffic tunnels, and also created an unusual structure for the tunnel.

The builders of the South-to-North Water Diversion Project dug two tunnels 40 meters deep at the bottom of the Yellow River bed west of Huayuankou, Zhengzhou. The Yellow River Tunnel is a double-line pressurized water tunnel with a single hole length of 4,250 meters and an inner diameter of 7 meters, which is enough for cars to run in the tunnel. With the "Yellow River Crossing Project", the Yangtze River water heading north meets the Yellow River in a three-dimensional intersection through the two Yellow River Crossing Tunnels. Normally, the Yellow River water flows on top, and the Yangtze River water of the South-to-North Water Diversion Project flows through the riverbed tunnel. The two pass up and down, like a giant dragon hiding under the Yellow River.

The South-to-North Water Diversion Program has greatly alleviated the shortage of water resources in Beijing. Currently, water from the south accounts for more than 70% of Beijing's urban water supply.

In terms of storing water from the south, Beijing has used the Miyun Reservoir Regulation and Storage Project, a supporting project of the South-to-North Water Diversion Project, to transfer water in reverse, with a total storage volume of about 800 million cubic meters to Miyun Reservoir, Huairou Reservoir, Daning Regulation and Storage Reservoir, Mingling Reservoir, etc. On the other hand, Beijing has also carried out experimental water replenishment for groundwater sources with conditions, and the water level has risen significantly.