Danjiangkou Reservoir is the water source of the middle route of the South-to-North Water Diversion Project. (PHOTO: XINHUA)

By LU Zijian

    The imbalance of water resources, more plentiful in the south than that in the north, has been a worrying issue for China for decades. In order to rectify the situation, the South-to-North Water Diversion Project was launched after many year's construction.

    On December 12, 2014, the middle route of the project began operation, supplying water for Beijing, Tianjin and other cities on the North China Plain.

    By January 7, water transferred by the project had reached 50 billion cubic meters, benefiting 140 million people.

    Mega project

    The southern region of China enjoys abundant water resources, which can even cause floods or heavy rains. But the northern region, conversely, is faced with a severe water shortage.

    The South-to-North Water Diversion Project was proposed to solve this problem. The overall plan of the project was approved in 2002 after decades of research. The construction work began at the end of that year.

    According to the overall plan, there are three routes of water diversion.

    The middle route starts from the Danjiangkou Reservoir in central China's Hubei province and flows across Henan and Hebei before reaching Beijing and Tianjin.

    The eastern route transfers water from Jiangsu province to areas including Shandong province and Hebei province.

    The western route is still under planning.

    As the middle route supplies water for Beijing, it has drawn more attention than the other two.

    Pipelines are used to transfer water in urban areas of Beijing and Tianjin along the middle route, which reduces the waste of water and prevents its pollution.

   Miyun Reservoir in Beijing. （PHOTO: XINHUA）

    Overcoming water imbalance

    Thanks to the project, people living in the northern region of the country have been relived from water shortage.

    More than 70 percent of the water supply in the urban areas of Beijing comes from the south, and almost all water used by residents in the main urban area of Tianjin is provided by the project.

    The quality of drinking water has also been improved. The hardness  of tap water in Beijing dropped from 380 mg per liter to 120 mg per liter. More than five million people, who live along the basin area of Heilonggang River in Hebei, no longer have to drink bitter, salty water.

    By the end of 2020, the groundwater level in the plains area of Beijing had risen 2.37 meters higher than that of 2014, increasing for six consecutive years. Miyun Reservoir, the biggest reservoir in Beijing, broke its historical volume record on August 23, 2021, reaching 3.358 billion cubic meters.

    The middle route has also provided more than seven billion cubic meters of water to more than 50 rivers in the north, and helped the Yongding river see its 865-km riverway, which was dry in most part,  filled with water for the first time since 1996.

    Added benefits

    The project is not only relieving the water scarcity in the north but also bringing more benefits for different regions.

    The environment in the Danjiangkou area has been greatly improved thanks to the flow of clean and safe drinking water flowing through central China. Plans are in place for the prevention and control of water pollution in the upstream of Danjiangkou Reservoir.

    Since then, the capability of sewage treatment of designated cities and counties has increased to 1.74 million tons per day, and the ability of disposing garbage to 8,950 tons per day.

    More than 500 enterprises which generated heavy pollution were shut down. The harsh policies on polluting enterprises have also seen them transform to a greener and more circulating business model.

    Ecological industry systems have been primarily established in certain districts, ensuring that development does not increase pollution. The condition of agricultural production has also been greatly improved with adequate water supply.

    The South-to-North Water Diversion Project has learned from other water systems, and it offers a Chinese solution to resolve the imbalance of water resources.