On the clear and winding Yongding River, there is a "Gyeonggi Pearl", which is the first large-scale reservoir in New China, spanning Yanqing in Beijing and Guanting Reservoir in Huailai, Hebei. Since its completion in 1954, the Guanting Reservoir has impounded eight major floods, nourished the people of Beijing, and has also withdrawn from Beijing's urban water system due to water pollution. On May 13, the reservoir will celebrate its 70th birthday. Looking to the future, it is on the road back to drinking water sources.
Guarding the "Wuding River" to the "Yongding River"
Guanting Reservoir / Photo by reporters
In late spring and early summer, looking at the Guanting Reservoir from afar, surrounded by green mountains, the water and the sky are the same. Nearby, a breeze blows, ripples, and birds fly by from time to time.
"When I retired, the water was yellow, and the surroundings were not so good-looking," Liu Zhengyuan, an 85-year-old veteran of the official hall, has been retired for more than 30 years, walking on the barrage dam, he couldn't help but sigh, "Now the water looks green, the environment is also very good, relatively clean, you can see birds in the water, it is indeed a good place to raise people." ”
Liu Zhengyuan on the dam of the reservoir / photographed by reporters
Before it became the Guanting Reservoir, it was the Guanting Mountain Gorge with high mountains and deep valleys and ravines, and it was also the main source of the Yongding River flood. As the mother river of Beijing, the Yongding River has been flooded continuously in history, and has burst 81 times in more than 800 years, making the people along the river miserable, so it is also known as the "Wuding River".
Jiang Shujun, head of the dispatching and operation section of the Guanting Reservoir Management Office, said that the upstream basin of the Guanting Reservoir is very large, covering more than 40,000 square kilometers, and there is no controlled reservoir project, so floods have often occurred in history, causing major floods in the lower reaches and posing a threat to Beijing and Tianjin. After the founding of the People's Republic of China, the state attached great importance to the flood control work in the Haihe River Basin, so it decided to build a large reservoir in the Yongding River.
Courtesy of Guanting Reservoir / Guanting Reservoir Management Office
In October 1951, under the personal organization and command of Premier Zhou Enlai, the construction of the Guanting Reservoir was started. In May 1954, the Guanting Reservoir was completed, and the dam was built between the two mountains, cutting off the once menacing Yongding River. Since then, it has become an important barrier to prevent the flood of the Yongding River from threatening Beijing, and it is also the first "Dinghe Divine Needle" in the history of water conservancy in New China.
In the 70 years since its construction, the Guanting Reservoir has been dampened by eight major floods of more than 1,000 cubic meters per second. In 1953, when the reservoir was still under construction, the flood peak reached 3,400 cubic meters per second, and through the storage of the reservoir, the flow downstream was only more than 800 cubic meters per second, a reduction of 70%. In several other major floods, all the reservoirs were impounded, and the flood retention rate reached 100%, truly realizing the Yongding River from "uncertain" to "Yongding".
In 1953, thousands of workers participated in the construction of the Guanting Reservoir / Workers' Daily Hou Yinfeng photographed
Forced to withdraw from Beijing's drinking water sources
In addition to quelling the floods of the Yongding River, the Guanting Reservoir has also become a source of drinking water for the citizens of Beijing and supplies agricultural, industrial and domestic water to the Beijing-Tianjin-Hebei region. Liu Zhengyuan, who came to work at the Guanting Reservoir in 1956, remembers that the water quality of the reservoir was good, the water volume was large, and the fish tasted delicious. However, since the 70s of the last century, the upstream rivers have become increasingly polluted, and the reservoir has gradually become a large pond for pollutants.
Jin Guiqin, chief technical engineer at the Beijing Institute of Water Science and Technology, said that the main cause of pollution was that the upstream toxic and harmful industrial wastewater was discharged directly into the river without treatment. In 1976, the water quality of the reservoir was again up to the second class standard for surface water. The Guanting Reservoir water pollution incident has also become a symbol of the beginning of China's water pollution control.
Nowadays, the scenery around the reservoir is beautiful / from the Internet
Unfortunately, the good times were short-lived. The results of pollution control in the Guanting Reservoir only lasted about 10 years, and the water quality deteriorated again, and the water quality dropped to Class 5 or even inferior during the dry season.
In the mid-to-late 80s, with the further rapid economic and social development of the upstream areas, the water consumption for production and domestic life has further increased, and the wastewater is still directly discharged into the river without treatment. At that time, the water body of the Guanting Reservoir often smelled foul. Later, coupled with the continuous drought in the North China Plain, the amount of water coming from the reservoir was further reduced, and the amount of sewage in the incoming water was large and the amount of clean water was relatively small, resulting in the failure of the Guanting Reservoir to "come back to life".
There were a few years in the 1990s when water was so scarce that people could even walk across the water that is now 10 miles wide. In May 1997, the heavily polluted Guanting Reservoir was forced to withdraw from Beijing's drinking water source system and was only used for industrial water and environmental water for urban rivers and lakes.
Courtesy of Guanting Reservoir / Guanting Reservoir Management Office
Protect a pool of clean water
In 2001, the Beijing Municipal Government and the Ministry of Water Resources formulated the Plan for the Sustainable Utilization of Water Resources in the Capital in the Early 21st Century (2001-2005), proposing to "protect Miyun and save the government". Since 2003, a series of engineering measures have been carried out to improve the water quality of the Guanting Reservoir.
Li Xiaohong, director of the Guanting Reservoir Management Office, said that at that time, the construction of the black soil depression wetland, the construction of ecological conservation forests in the reservoir coastal zone, the closure of the reservoir and the ban on fishing, and the implementation of engineering measures such as the prevention and control of blooms and the reuse of reclaimed water, carried out comprehensive treatment of the water environment of the reservoir. At the same time, the upstream and downstream basins of the reservoir have been de-polluted by establishing ecological protection zones and sewage treatment plants.
By 2007, the Guanting Reservoir had been restored to function as a backup source of drinking water for Beijing.
Collecting water samples from the reservoir/Photo by Wang Weiwei of the Workers' Daily
With the implementation of the "Overall Plan for Comprehensive Management and Ecological Restoration of Yongding River", in 2019 and 2021, the No. 8 Bridge Wetland and the Fushui River Wetland upstream of the Guanting Reservoir were completed and put into use successively to further purify the upstream water from the reservoir.
In the No. 8 Bridge Wetland, located in the beach at the mouth of the Yongding River, the upstream Sanggan River and the Yanghe River flow from west to east after converging into the main stream of the Yongding River, and the water of the main river channel slowly flows into the 211-hectare artificial wetland under the action of the barrage. After 72 hours of purification, it flows into the Guanting Reservoir.
The No. 8 Bridge Wetland starts from the Daqin Railway in the west to the No. 8 Bridge Hydrological Station in the east, and uses a river channel with a length of about 3.5 kilometers and a river channel and beach land with a width of about 700 meters to build a large-scale surface flow wetland, with a stream wetland on the left bank and a forest wetland, island wetland, and unit wetland on the right bank.
Bridge No. 8 Wetland/Photo by reporters
Fu Xinlei, director of the Yongding River Reservoir Bank Management Office of the Guanting Reservoir Management Office, said that there are three water retaining weirs on the main river channel of the wetland, and the water level of the upstream river is adjusted through the gate of the weir to introduce water from the main river into the wetland, which slows down the water flow rate and increases the residence time of the water body, thereby improving the effect of aquatic plants and organisms on water purification. After the water of the river enters the wetland, it is purified, and the removal rate of ammonia nitrogen, total phosphorus and total nitrogen can reach 26%~88%, and the effluent water quality can basically reach the level of three types of water.
Since 2003, a total of 1.2 billion cubic meters of upstream water has been treated in the Heituwa Wetland, No. 8 Bridge Wetland and Fushui River Wetland, and the purification effect of the water flowing through the wetland is remarkable, and the removal rate of total nitrogen and ammonia nitrogen is the most obvious, reaching more than 50%. The water quality in the reservoir area has improved significantly, and the main indicators have basically stabilized at the three types of standards.
Courtesy of Bridge No. 8 Wetland/Guanting Reservoir Management Office
Courtesy of the Fushui River Wetland/Guanting Reservoir Management Office
The water storage capacity is at a record high
While the water quality is improving, the problem of water shortage is also being solved step by step. With the centralized water transfer from the upstream Cetian Reservoir and Yanghe Reservoir to the Guanting Reservoir, especially the implementation of the ecological water flow dispatch from the Yellow River to Beijing in 2019, the Yellow River, the "mother river" of the motherland, and the Yongding River, the "mother river" of Beijing, have achieved a historic "hand-in-hand", and the water storage of the Guanting Reservoir has steadily rebounded.
Wu Yuxin, director of the Guanting Reservoir Operation and Maintenance Management Institute, came to work in Guanting in 2006, "When I first went to work, I felt that the water surface was very small, and when I opened the spillway gate, the water could not be released. ”
Through the upstream reservoir, water was gradually dispatched to the Guanting Reservoir, and the water in the Guanting Reservoir rose little by little. "In 2022, the water level reached 47.63 meters, and the water storage reached 692 million cubic meters, a new high in more than 20 years. At present, the scenery and environment of the reservoir area are relatively good, and the water surface is also open. Wu Yuxin said.
Guanting Reservoir replenishes water to the Yongding River downstream/Photo by Pan Zhiwang of Beijing Daily
In November 2017, the Guanting Reservoir started an initial attempt to replenish the ecological water of the Yongding River downstream. In the past few years, the cumulative water supply has reached nearly 2 billion cubic meters, making the Yongding River open to water, and last year was the first time that the whole line has been watered since the interruption of the flow in 1996. Beijing's "Mother River" was reborn, and the Guanting Reservoir was once again full of vitality.
Through monitoring, the biodiversity of the reservoir has increased significantly, and migratory birds have migrated frequently. A total of 115 species of birds have been observed in the reservoir area, including black stork, relict gull, Baer's Pochard and other national first-class protected birds, including black-faced spoonbill, great bustard and other endangered and rare birds have made their home in the reservoir. "In February this year, a large number of swans migrated to the Guanting Reservoir, and 18,000 were monitored in one day. At present, the ecological effect of the wetland has been obvious, and it has played a barrier of ecological security for the good economic and social benefits of the surrounding area. Li Xiaohong said.
Guanting Reservoir "Flying Birds into Clouds"/Photo by Xinhua News Agency Huang Xiaoyong
Swans foraging in the Guanting Reservoir/Beijing News Photo by Li Muyi
The road back to the source of drinking water
The Beijing Urban Master Plan (2016-2035) calls for the restoration of the Guanting Reservoir's function as a drinking water source by 2035. At present, the Guanting Reservoir has been restored to a backup water source in Beijing, and the water quality does not meet the requirements of a standing drinking water source for the time being. Li Xiaohong, director of the Guanting Reservoir Management Office, revealed that there are about 650 million cubic meters of silt in the Guanting Reservoir, and 11 million cubic meters of dredging will be carried out this year, which is expected to bring qualitative changes to the improvement of the water quality of the Guanting Reservoir.
Li Xiaohong said that there are some pollutants in the sediment that will return to deteriorate the water quality, so in order to improve the water quality permanently, the sediment must be dredged or treated. At present, the total sediment volume of the reservoir in the reservoir area is relatively large, if all of them are treated, the construction process is more difficult, and where can such a large amount of silt be absorbed, can it be used as a resource? "We need to do deeper research through the pilot project, and if the pilot is successful, the next step will be to desilt a large area."
Courtesy of Guanting Reservoir / Guanting Reservoir Management Office
On the way to return the Guanting Reservoir to the source of drinking water, the Beijing water affairs department will also carry out ecological construction in the reservoir coastal zone, further improve the water ecological environment in the reservoir area, and realize the fully closed management of 220 kilometers of the reservoir area.
Ecological water replenishment plays an important role in the replacement of water bodies in Guanting Reservoir, and it is necessary to strengthen regional cooperation to allow more and better upstream water to enter the reservoir to improve water quality. "We also need to strengthen operation and scheduling, to continue to strive for the upstream diversion and replenishment of water and centralized water transportation, and in Beijing can strengthen the Baihebao Reservoir continuous transfer and replenishment, to continue to improve the water quality of the reservoir area, but also for the ecological restoration of the Beijing section of the Yongding River and the groundwater storage area in the western suburbs to provide water source and water quality guarantee." Jin Guiqin, chief technical engineer of Beijing Institute of Water Science and Technology, said.
Flocks of birds in the Guanting Reservoir / from the Internet
After 70 years of ups and downs, the Guanting Reservoir has gone through an extraordinary development process. The current water quality monitoring data shows that the main water quality indicators in the Guanting Reservoir area have basically reached the level of three categories, and it is just around the corner to return to the ranks of water sources in 2035. Wang Hongrui, a professor at the Institute of Water Sciences at Beijing Normal University, said that the return of the Guanting Reservoir in the future is of great strategic significance to Beijing, which is short of water resources.
Wang Hongrui said that Beijing is a city with a serious shortage of water, and there are only two basins of water, one is the Miyun Reservoir and the other is the Guanting Reservoir, and the middle route of the South-to-North Water Diversion Project is an important supplement for Beijing's external water transfer. At present, about 1 billion cubic meters of water is transferred from the south to the north every year, but it is far from enough compared to Beijing's total population and industrial and agricultural water. After the Guanting Reservoir is restored to become a source of drinking water in Beijing, it can increase Beijing's strategic water reserves, become an important supplement to improve the spatial balanced allocation and guarantee of water resources for the first time, and provide support for the green and high-quality development of the capital.
Reporter Wang Chenchen, Editor Sun Yuan, Editor-in-Chief Cheng Yan