Core Reminder: It is often said that Yan'an lacks water. Why does it lack water? What is the current state of water resources? Why do experts say "water shortage has become a bottleneck constraining the continuous and stable development of Yan'an's economy and society"?
Recently, the Yan'an Municipal Party Committee and Municipal Government successively agreed to implement the "Yellow River Water Diversion to Yan'an" project to solve the city's second water source issue. With an investment of 929 million yuan, water will be diverted from the Yellow River to Yan'an through pipelines spanning 136 kilometers. How did this plan come about, and what scientific basis does it have?
Severe Current Situation: Per capita water resources are only 30% of the national average.
Core Data:
- Per capita water resources: 649 cubic meters
- 78% of land area suffers from soil erosion
- 23 sewage outlets fail to meet emission standards
- Estimated water shortage in 2010 will reach 70 million cubic meters
Yan'an is a region with resource-based water scarcity. For many years, the per capita water resources in Yan'an have been only 649 cubic meters, which is just 30% of the national average and 56% of the provincial average. The internationally recognized minimum per capita water requirement is 1000 cubic meters.
Soil erosion in Yan'an is extremely severe, with the current soil erosion area reaching 28,800 square kilometers, accounting for 78% of the total land area. Short but intense rainfall results in high sediment content in surface runoff floods, making it difficult to store and utilize the water effectively.
"Although the city has built more than 44,000 water conservancy projects of various types, there is a lack of control-oriented backbone water source projects, leading to poor storage capacity," said Zhang Qiang, Director of the Yan'an Water Resources Administration. The city currently has 29 reservoirs with a total capacity of 529 million cubic meters, but 48% of the total capacity has already silted up, and the effective capacity continues to decrease annually. In 2005, Yan'an experienced a water shortage of 25 million cubic meters. "It is estimated that by 2010, the city's water shortage will reach 70 million cubic meters."
Water Supply in 2030 Will Only Meet One Third of Demand
Currently, the main water sources for the urban area of Yan'an include the Wangyao Reservoir, Hongzhuang Storage Reservoir, self-provided water sources in the urban area, and supplementary water sources from the Beiguan Water Plant.
Self-provided water sources in the urban area can only be used for residents living above the mountainous areas and temporary use. The Beiguan Water Plant's supplementary water source has low reliability and poor water quality, serving only as an emergency water source. The Hongzhuang Reservoir can only improve the water supply guarantee rate of the Wangyao Reservoir water supply project. The Wangyao Reservoir is currently the only reliable water source for the urban area of Yan'an, with a total capacity of 203 million cubic meters. However, 115 million cubic meters have already silted up, with an annual water supply of 12.27 million cubic meters and a daily water supply capacity of 50,000 cubic meters.
Currently, the urban area of Yan'an mainly relies on the combined scheduling of water supply from the Wangyao Reservoir and the Hongzhuang Reservoir. Considering factors such as reservoir siltation, the water supply volume will gradually decrease, and by 2030, it will only be able to supply 11 million cubic meters. According to investigations and predictions by relevant units in Yan'an, the urban population will reach 500,000 by 2030, with a total water demand reaching 37.4934 million cubic meters.
Random checks on 36 drinking water sources revealed that 23 were polluted.
In recent years, with large-scale development of mineral resources such as oil and coal, as well as the acceleration of urbanization, the discharge of industrial wastewater and domestic sewage in Yan'an has increased year by year. Coupled with low sewage collection and treatment capabilities, rivers have generally suffered varying degrees of pollution. "These pose significant challenges to the current water supply and future development and utilization, making limited water resources even scarcer," said Zhang Yongfeng, Director of the Water Resource Management Department of the Yan'an Water Resources Administration.
In 2005, the Yan'an Water Conservancy Bureau commissioned the Shaanxi Provincial Water Environment Monitoring Center Yan'an Branch to conduct a comprehensive investigation of the city's water quality and produce an evaluation report. The results showed that among the 1390 kilometers of river length evaluated (accounting for 80% of the total river length), there were no Class I water quality river sections within Yan'an's jurisdiction. There were only 15 kilometers of Class II water quality, accounting for 1% of the total length. Among the 36 drinking water sources randomly checked that year, 23 were polluted. Among the 26 groundwater wells checked, none met Class I or Class II water quality standards. All 23 monitored sewage outlets failed to meet emission standards.
"After extensive research by many experts, we believe that the coexistence of resource-based water shortages, engineering-based water shortages, and pollution-based water shortages is a prominent issue in the current development and utilization of Yan'an's water resources. Water shortages have become a bottleneck constraining the continuous and stable development of Yan'an's economy and society," said Zhang Qiang, Director of the Yan'an Water Resources Administration, with concern.
Finding New Water Sources: Four Plans Selected "Yellow River Water Diversion to Yan'an"
Core Data:
- Estimated total investment: 929 million yuan
- Water supply capacity in 2030: 48.6229 million cubic meters
- Yan'an will no longer worry about water for decades
To ensure the sustainable development of Yan'an's economy and society in the future and alleviate the contradiction between water supply and demand, the Yan'an Municipal Party Committee and Municipal Government began actively seeking new water sources several years ago.
"According to the principle of prioritizing the development and utilization of surface water and restricting the development and utilization of groundwater, based on the distribution and reserves of Yan'an's water resources, the main focus for future water supply in Yan'an's urban area should be on the three major tributaries of Yanhe River, Beiluo River, Qingjian River, and the main stream of the Yellow River," said Zhang Qiang. After exploration and argumentation, four plans - Long'an Reservoir, Yindongjiyan, Zhouhechuan groundwater, and Yellow River Water Diversion to Yan'an - successively emerged.
After scientific argumentation, last year in the second half, the municipal government in principle approved the "Yellow River Water Diversion to Yan'an" project plan. On May 22, 2023, reporters learned from the Yan'an Water Conservancy Bureau that the Yan'an Municipal Party Standing Committee had discussed and approved the selection of the "Yellow River Water Diversion to Yan'an" plan as Yan'an's second urban water source. "Preparatory work is proceeding in an orderly manner."
Plan One: Building "Long'an Reservoir" Costs Too Much and Takes Too Long
Yanhe River is Yan'an's second largest river, originating in Gaomao Mountain, Jingbian County, Yulin, and flowing through Ansai, Bao塔 District, and Yanchang counties in Yan'an. "The annual flow of Yanhe River varies greatly, with extremely uneven distribution throughout the year. The flow is usually very small, with a long dry season, and even continuous water cutoffs occur," said Zhang Yongfeng, Director of the Water Resource Management Department of the Yan'an Water Resources Administration. Large-scale oil development in the Yanhe River basin has led to serious water quality pollution.
Xichuan River is a tributary of Yanhe River. Its water inflow basically cannot meet the water needs of Yan'an's urban area. The population density in the basin is high, with many cultural relics and ancient sites (including Yangjialing and Zao Garden). Moreover, Provincial Road 303 passes through the basin, making it unsuitable for building a reservoir. Therefore, it cannot serve as the second water source for the urban area.
Similarly, Nanchuan River, another tributary of Yanhe River, although having better vegetation upstream and lower river turbidity, has limited total water volume. Because railways and highways pass through its valley floodplain, the water quality seriously exceeds standards, and the difficulty of water source protection is exceptionally high. Therefore, it does not have the basic conditions to serve as the second water source for the urban area.
Rejecting Yanhe River means rejecting the "Long'an Reservoir" plan among the four options, as the proposed Long'an Reservoir is located in Long'an Village, Huaziping Township, Ansai County, along the main stream of Yanhe River. The construction of this reservoir was proposed as early as the 1970s.
However, the proposed Long'an Reservoir would require the relocation of 3,113 households, totaling 12,900 people, with the relocation alone costing approximately 650 million yuan. Additionally, a large number of oil wells, gas wells, gathering stations, oil pipelines, power lines, telecommunications lines, broadcasting lines, and local enterprises would need to be submerged, with preliminary estimated compensation funds requiring approximately 1.45 billion yuan. Furthermore, there are 5 kilometers of already-built highways and 20 kilometers of provincial roads within the submerged area, requiring rerouting at an additional cost of 1.1 billion yuan. "All together, it would require over 5.85 billion yuan, making fundraising difficult, with a long construction period and significant implementation challenges. It is not suitable as a medium- to long-term water supply source for the urban area," said Zhang Qiang.
Plan Two: "Yindongjiyan" Requires Pollution Control First
Beiluo River is a secondary tributary of the Yellow River and is Yan'an's largest river, originating in Baiyu Mountain, Dingbian County, Yulin. Its main stream flows through six counties in Yan'an: Wuqi, Zhidan, Ganquan, Fuxian, Luochuan, and Huangling. However, the baseline water quality of the Beiluo River's source is poor, primarily due to excessive chlorides. An engineer from the Yan'an Water Conservancy Bureau stated that before 1996, the water quality monitoring results at the Shimen water intake point were basically up to standard, but by 2004, the monitoring results showed that the water quality had deteriorated to Class V, failing to meet drinking water source standards. Additionally, "with the economic and social development of the Luo River Basin and the construction of petrochemical bases, the contradiction between water supply and demand will become increasingly severe. Therefore, we recommend treating pollution before developing the Luo River Basin, using it as a reserve water source for Yan'an."
Plan Three: Groundwater in Zhouhechuan Area Is More Needed by Surrounding Counties
One of the four initial plans included the groundwater in the Zhouhechuan area. This area has favorable groundwater-rich sections, with the most reasonable groundwater source located in Zhidan County, buried 700 to 800 meters underground.
"Just the exploration alone would cost over 20 million yuan! Since no exploration has been conducted in this area, the groundwater reserves, replenishment range, and replenishment sources are unclear," said Zhang Qiang. Additionally, both Zhidan and Wuqi counties in the Zhouhechuan area lack surface water suitable as a drinking water source, so consideration should be given to reserving this area's groundwater for the development of these two counties.
As Yan'an's third largest river, the Qingjian River originates in Zichang County. Its basin is one of the most severely eroded areas in the middle reaches of the Yellow River. "Reservoirs such as Zhongshan Reservoir and Hansha Stone Reservoir have already been built in the basin, mainly serving as water sources for Zichang County, Yanchuan County, and Yongping Refinery. The available water resources have already reached their limit." Moreover, the severe pollution of water resources caused by the development of oil, coal, and other resources in the basin makes both the quantity and quality of water unsuitable as Yan'an's second urban water source.
Plan Four: "Yellow River Water Diversion to Yan'an" Provides Adequate Water Supply and Benefits a Wide Area
Experts and the Yan'an Municipal Party Committee and Municipal Government have unanimously focused on the "Yellow River Water Diversion to Yan'an" plan. The original "Yellow River Water Diversion to Yan'an" project plan had two options.
The first option is called the "Yanhe Line," which involves taking water from Liangshuiyan near the mouth of the Yanhe River in Yanchang County and conveying it to Dongguan in Yan'an City along the Yanhe River. The estimated total investment is 982 million yuan.
The second option is the "Yanchuan Line," which proposes taking water from Wangjiaqu in Yanshui Pass Town, Yanchuan County. The water pipeline enters Yanchuan County and then splits into two branches. One branch conveys water to Yongping Refinery and reserves a water outlet for Zichang County; the other passes through Wenanyi Town and Yujuzhen Town, reserving a water outlet for Yanchang County in Wenanyi Town, then proceeds through Ganguyi Town, Yaodian Town, and Liqutan Town to enter Yan'an City, while setting up a water outlet for the new industrial district of Yaodian Town. The pipeline is approximately 136 kilometers long, with an estimated total investment of 929 million yuan.
After comparing the Yanhe Line and Yanchuan Line options, the Yan'an Municipal Party Committee and Municipal Government believed that the Yanchuan Line was superior to the Yanhe Line in terms of water diversion height difference, pipeline distance, beneficiary scope, construction investment, and operating costs. Therefore, the Yanchuan Line was ultimately determined to be the final plan for the Yellow River Water Diversion to Yan'an project.
"Choosing this plan not only ensures that Yan'an's urban area has a sufficient second water source, but also benefits counties such as Yanchuan, Yanchang, and Baota District," said Zhang Qiang. Diverting Yellow River water enhances Yan'an's water resource carrying capacity. Besides solving Yan'an's mid- to long-term water supply problems, the current water source for the urban area, Wangyao Reservoir, can adjust its water supply direction to meet the future water needs of Ansai County nearby.
"Solving the production and living water needs of Yongping Refinery changes the current situation of diverting water from Xiuyan Second Channel and Zhongshan Reservoir in Zichang County, indirectly solving Zichang County's future water needs."
According to expert scientific estimates, after the completion of the Yellow River Water Diversion to Yan'an project, it will be able to supply 48.6229 million cubic meters of water to Yan'an's core urban area in 2030, while the estimated total water demand for that year is only 37.4934 million cubic meters. "For decades or even further into the future, Yan'an's urban area will no longer worry about water shortages."
It is understood that the water resources argumentation report for the Yellow River Water Diversion to Yan'an project has been reviewed and approved by the Yellow River Conservancy Commission. The soil and water conservation plan for the project has also been reviewed and approved by the provincial water conservancy department. The flood impact assessment report for the project, after being preliminarily reviewed by the provincial water conservancy department, was reviewed and approved by the Yellow River Upper and Middle Reaches Administration Bureau in December 2006. Its environmental impact assessment report was reviewed and approved by the provincial environmental protection bureau in March this year.
The project is planned to start construction throughout the line next July, and the first phase of the project will be completed and put into trial operation by the end of 2010.