According to the principle of "relying on the old city, developing along the Chuanjiang River and harnessing the whole basin", Yan 'an New District has determined three major districts of the new district, with a planned control area of 78.5 square kilometers and a planned population of about 400,000. In terms of construction sequence, it is determined to implement the first phase of the North District, with a land scale of 10.5 square kilometers and a construction period of 4 years. The total earthwork volume of the project is 363 million cubic meters, including 200 million cubic meters of excavation and 65.438+63 million cubic meters of filling.

On the morning of April 12, the first phase of Yan 'an New Area (North Area) was officially started, which is one of the largest geotechnical projects in collapsible loess area in China. The first phase of the North District Project is located in Qiaogou Town, Baota District, with a construction area of 10.5 square kilometers, with an estimated total investment of 5.3 billion yuan and a construction period of 4 years. It is reported that Yan 'an's population is expanding rapidly, and it is urgent to broaden the urban framework and seek new development space. Yan 'an is implementing the development strategy of "expanding from China to the outside and building a city by mountains", which is not only conducive to alleviating the shortage of urban land reserve resources, but also conducive to protecting revolutionary sites in the old city, promoting the development of tourism, stimulating healthy and sustained economic growth and improving the living environment.

New area north zone

Located in the north of the north-south central axis of Liang Qing, Yan 'an, it is backed by the main vein, surrounded by mountains from east to west, facing the Yanhe River and overlooking the pagoda. The North District is planned as a municipal administrative center, focusing on the development of modern commerce, financial services, education and training, reflecting the modern ecological new city style. The planned control area is 38 square kilometers, and the carrying population is 1.5-0.2 million. The spatial structure is "one heart, two axes, five zones and six corridors". Focus on the municipal administrative office area; The two axes are the north-south landscape axis and the east-west commercial axis respectively; These five districts are administrative district, commercial district, three educational districts and two residential districts. Six corridors are six ecological green corridors. Form the overall layout of group growth with green corridors, main roads in series and multi-level support.

New area east zone

Located in the southeast of Baota shan, on the south bank of Yanhe River, facing the North District New Town across the river. It is planned to be a district-level administrative center, focusing on the development of sports, tourism services, leisure vacations and high-end residential groups that reflect the regional characteristics of the loess, making it a modern ecological new city with distinctive regional characteristics. The planned control area is 32.3 square kilometers, and the carrying population is 1.5-0.2 million. The planning structure is "one corridor, two wings and six districts". A corridor is along the original mountains and ditches, forming a green landscape corridor in the middle; The two wings refer to the functional areas on both sides of the green landscape corridor; The six districts are district-level administrative center, living and residential area, urban industrial area, leisure and entertainment area, physical education area and tourism service area.

New area west area

Located on the west side of Fenghuang Mountain, adjacent to the old city. Take red culture as the core, develop cultural tourism industry and create a new "window" to display the historical memory of Yan' an, the holy land. The planned control area is 8.2 square kilometers, carrying a population of 20,000-30,000 people. Taking the restoration of important historical buildings in the holy land as the main line, we will explore and expand the red culture and feel the years of the holy land.

The planning of Yan 'an New District is divided into three areas, with a control area of 78.5 square kilometers and a carrying population of more than 400,000. It is divided into North District, East District and West District.

According to the development strategy of "expanding from the middle to the outside and building a city by the mountains", Yan 'an will "cut mountains and fill ditches and build land to build a city", and it will take 10 years to finally sort out the construction area of the new district of 78.5 square kilometers, and build a new city twice as large as the old city in the gully area around the city. Yan 'an "cutting mountains to build cities" project is the largest geotechnical engineering in collapsible loess area in the world, and it is also the first case in the history of building cities in the world. Like many urbanization processes that rely on debt financing, the grand plan of Yan 'an new city construction may hide uncertain risks. The surrounding environment of Yan 'an city 168 revolutionary sites is constantly being invaded and eroded, and it is difficult and stressful to protect revolutionary sites and historical and cultural cities. "This situation is extremely disproportionate to the status of the revolutionary holy land and there is a big gap with the requirements for developing red tourism." Expanding new urban development space and gradually improving urban functions have become the top priority of Yan 'an's urban development. However, a "land" is hard to find!

At the fourth Party Congress of Yan 'an City, Yan 'an City decided to implement the new urban development strategy of "expanding from China to the outside" and "building on the mountain". A new district with a total area of 78.5 square kilometers will be built in the hilly area around the city. It is declared that "on the occasion of the centenary of the founding of the Party in 20021,a new Yan 'an, which embodies history and modernity, has a complete urban structure and advanced management, will be presented to the whole party and the people of the whole country".

The construction of Yan 'an New District is undoubtedly a "big plan" and a "big plan", which is equivalent to rebuilding the area of two old Yan 'an cities on the mountain. Yan 'an "cutting mountains to build a city" project is the largest geotechnical engineering in collapsible loess area in Asia and even the world, and it is also the first case in the history of building a city in the world. 17th western conference, Yan' an new district signed four projects with a total investment of115.36 million yuan. There are 19 projects with intention to agree, involving the comprehensive development of new areas, municipal infrastructure, energy and other major industries.

It is reported that Yan 'an New District of the Western Conference brought 40 projects in six categories: urban infrastructure, public services, municipal facilities, cultural tourism, high-tech, financial services, new energy and engineering services, among which the municipal administrative center and affiliated projects signed a contract with China Construction Group with a contracted capital of 65.438+77 billion yuan; Yan 'an New District (North District) connecting road construction project (walnut tree tower connecting road, small ditch connecting road, Yang Jialing connecting road, bridge and ditch connecting road) signed a contract with the Fifth Engineering Group Company of China Railway 18th Bureau with a total investment of 656 million yuan; The cooperation project of concrete mixing station signed a contract with Shaanxi Floriculture Construction Engineering Co., Ltd., with a total investment of 654.38 billion yuan; The cooperation project of concrete precast component factory signed a contract with Shaanxi Hongyi Industry and Trade Co., Ltd.; The contracted amount is 50 million yuan.

At the current Western Conference, Yan 'an New District also held a special promotion activity of "Yan 'an New District Key Project Promotion Conference and Signing Meeting" in the special activity of Yan 'an of the 4th Global Qin Merchants Conference. That area will become a new municipal center in the future, and a big ravine below will be filled up. "Liu Gongyi pointed to a row of engineering mobile homes halfway across the mountain, depicting the future of Yan 'an New District.

"Building a new district is a helpless choice." This scholar is a member of the Party Working Committee of the Management Committee of Yan 'an New Area and deputy director of the Management Committee.

Yan 'an is surrounded by Liang Qingshan, Phoenix Mountain and Baota shan, and divided by Yanhe River and Nanchuan River. Located between three mountains and two rivers, the urban development space is squeezed, so we can only find a way out between mountains and rivers.

Yan' an city extends along three Sichuan roads, and the whole city is stretched and leveled, while buildings compete with mountains for land, but there is a danger of collapse. How does Yan 'an develop in the crevice of three mountains and two rivers?

The bold idea of "expanding from the middle to the outside and building a city on the mountain" jumped out of the previous framework of Yan' an urban development, cut mountains and fill ditches, and opened up a new city on the top of the mountain. This is the construction idea of Yan 'an New District.

1. The urban skeleton is getting longer and longer.

The construction of Yan 'an New District once again attracted people's attention to Liang Qing. Ground is being broken here to build the north area of Yan 'an New District, and the headquarters of Yan 'an New District Construction is also built on this top of the mountain.

According to the plan, Yan 'an New District is divided into three areas. First, the North District, with an area of 38 square kilometers, is mainly the municipal administrative center, business center, business center and residential area. One is the 32-square-kilometer southern district, which is mainly a district-level administrative center and built into an experience area of red culture; There is also a 3. 1 square kilometer Phoenix community, which is dominated by tourism.

The river runs through the city surrounded by three mountains. The roads in Yan 'an, like urban space, develop along the river on Sichuan Road. There are two main roads on both sides of the river, and many roads are one-way.

Of course, there is a more realistic demand for building a new city. There are 65438+ ten thousand people living in the mountains in Yan 'an city, and they can't supply water, gas or heat. Deng, director of the Political Research Office of Yan 'an Municipal Committee, told the reporter that after the completion of the new city, the residents on the mountain will move. They still live in caves, and their living conditions are similar to those of farmers. It is planned to descend 654.38 million people, mainly to the new district.

Building a city on the mountain jumped out of the development mode of Yan' an along the narrow Sichuan Road. Due to the rapid development of the city, the skeleton of the city has been stretched for a long time in several Sichuan roads. In the east of the city, the city goes all the way to the airport.

What follows is not only the traffic problem, but also the cost increase of power supply, water supply, heating and gas supply pipeline laying.

The population of Yan 'an has reached 500,000, which makes people deeply feel the limitation of urban development space. According to the World Bank's forecast, the population of Yan 'an will reach 700,000 in 2030. If we don't expand the urban development space, the resettlement of new population will become a major problem in Yan 'an's urbanization development and urban-rural overall planning.

2. Is it feasible to cut mountains and build cities?

What is the impact of large-scale mountain opening and ditch filling in Yan 'an on natural ecology? Is there no other choice for this change? In the face of reporters' repeated questioning, a planning official in Yan 'an New District retorted: "Do you want Yan 'an to be urbanized or developed? Yan' an city can't be as narrow as a few hundred kilometers, so the traffic can't be solved! "

"We have organized more than 30 experts, and after seven discussions, it is the first time in China and may not be available internationally because of such a large-scale cutting of mountains and filling ditches." Liu Gongyi told reporters that this project is feasible after many arguments by experts.

In the northern part of the new area where construction has started, the gap between the new area and the old area is about 100 m after completion, and both foundation, water supply, drainage and soil and water conservation will face new challenges.

Yan 'an New District has also demonstrated the problem of changing geological form by cutting mountains and filling ditches. For those with poor geological conditions, the instability was eliminated by tamping many times, but the experiment in the old airport showed that the experimental settlement was only 4 cm.

Liu Gongyi pointed to the model in the northern part of the new area and told reporters that considering the stability of the foundation, the future buildings will be built on the original mountains, and the area created by filling ditches will mainly be used as green areas, and will not be built for the time being. Experts have different opinions on when the geology of the new urban area formed by land reclamation will stabilize. Loess experts believe that it will be stable for 3-5 years, and some experts think it will take 10 years.

"There used to be a dam near the new municipal center. If not handled, there may be a danger of tilting in urban construction. Not afraid of settlement, but afraid of tilt. When you are embarrassed, the building will fall down. " Liu Gongyi told reporters that the construction of the new district is very cautious about the treatment of the foundation.

Although the new town in the North District was built on the mountain, it was not built on the top of the mountain, but razed most of the mountainside of Liang Qingshan. The whole city is still surrounded by mountains and is in a position similar to a basin. However, this has also put pressure on the water supply in the new district. The drop of 100 meters requires a pumping station to transport water, and the cost of water supply is bound to increase.

Considering the bearing capacity of the foundation, the building height of the new area will be controlled, generally 50 to 60 meters. In the new town administrative center, the floor will not be very high, while the floor in the business district will be higher, but the maximum will not exceed 100 meters. Liu Gongyi told reporters: "This has two advantages. The first is to reflect the form of modern cities. The administrative center is a regional architectural landmark, and the business district is a modern landmark. The old city can see the new city; The other is standing in the business district overlooking the old city and Chengnan District. "

In the future, it can accommodate 200,000 people, the building density is much smaller than that of the old city, and the roads are much wider. By then, there will be six or seven roads connecting the north area and the old city. Due to the high building density in the old city, there is basically no green space except parks, while the vegetation coverage rate in the new city should reach more than 40%.

After cutting hills and filling ditches, the original natural drainage channels were artificially changed. If groundwater cannot be effectively discharged, will it cause geological collapse or settlement? Therefore, in the construction of Yan 'an New District, permanent blind ditch drainage was adopted to avoid the overall settlement caused by groundwater erosion.

But the cost of land can't be controlled by cutting mountains and filling ditches on such a large scale. It is roughly estimated that the cost of an acre of land is about 6.5438+0.6 million yuan. Liu Gongyi repeatedly stressed to reporters that the North District is not a simple development, but mainly to relieve the people in the old city. The construction of the new district is to solve the problems of living environment and road traffic, and improve the ecological environment of Yan 'an as a whole.

The logic of Yan 'an water control: not only for development, but also for safety.

How to realize urbanization and industrialization in such a water-deficient and ecologically fragile area?

1. Dilemma of water supply and flood control

Along the upper reaches of Yanhe River, 65 kilometers northwest of Yan 'an City is Yao Yao Reservoir, which is the only water source in Yan 'an and undertakes the important task of supplying water to Yan 'an City.

Yao Yao Reservoir is located on the Xing Zi River, a tributary of Yanhe River in Ansai County. It supplies 50,000 cubic meters of water to Yan 'an City every day, which solves the water problem of 500,000 people in Yan 'an City. However, the upstream inflow is getting less and less, while the population of Yan 'an is increasing, and the balance between supply and demand is gradually broken.

Nan, deputy director of Yao Yao Reservoir Management Office, pointed to a large area of water surface of the reservoir and told reporters: "The storage capacity of the reservoir is 203 million cubic meters, and there are still more than 5 million cubic meters of water. From here, we can see the siltation table, and the siltation has reached 654.38+26 million cubic meters, accounting for 62% of the storage capacity. After Yao Yao Reservoir 1997, it mainly supplies water to Yan 'an, with an annual water supply of150,000 cubic meters. "

Yanhe River flows through the hilly and gully region of the Loess Plateau, with serious soil erosion and large sediment concentration in the water, which is easy to cause reservoir siltation. In the upper reaches of the reservoir, due to the large-scale exploitation of oil, man-made destruction of vegetation has aggravated soil erosion.

Yao Yao Reservoir was built in 1970s. At the beginning, it was mainly used for flood control, irrigation and power generation, and there was no sand drain hole at the bottom of the reservoir. After several times of reinforcement and reconstruction, the problem of sediment discharge has not been effectively solved, so the empty reservoir can only be used to discharge sediment and reduce siltation.

After the reconstruction in 2004, according to the relevant regulations of Shaanxi Province, Yao Yao Reservoir must be operated once every two years, and flood discharge will be carried out in July and August to ensure that the mesa will not be silted.

For Yao Yao Reservoir, which still undertakes the flood control task, if the siltation is too large, the effective storage capacity of the reservoir will be reduced, so it will be unable to bear greater flood control pressure when the flood comes, and in the long run, the service life of the reservoir will be shortened.

Yan' an city has a flood control once every 30 years, and its flood control ability is insufficient. Zhao Qian 'an, director of Yan 'an Water Saving Office, told the reporter that the flood of 1977 flooded the urban area of Yan 'an, and many houses in Yan 'an North Street were washed away by the flood and later rebuilt.

"Now Yanan water supply is tight, and the reservoir has been unavailable for four years. I dare not open the reservoir, or there will be no water to eat in Yan' an city. " South Qi Xing says it is difficult to store 5 million cubic meters of water. If the reservoir is empty, all this water will be released in vain.

The emptying time of the reservoir happens to be the peak period of water use in summer. After Yao Yao Reservoir released water, Hongzhuang Reservoir, another downstream reservoir, stored more than 3 million cubic meters of water, which was only enough for Yan 'an to use for two months. After August, if there are few water games, it will be difficult to eat in Yan 'an in winter. In recent years, the overall rainfall is less, and the usual water inflow is very small. Yao Yao Reservoir mainly relies on floods in July and August to store water.

2. There are still hidden dangers in water supply.

Along the upper reaches of the river, drilling sites and engineering teams can be seen everywhere, and even "kowtowing machines" that are producing oil can be seen. There are more than 100 oil wells in Yao Yao reservoir area, and oil leakage has become a hidden danger threatening the water supply in Yan 'an.

At the end of August, 2007, a rainstorm triggered a landslide, which led to the fracture of an oil pipeline in Changqing Oilfield, which is located in the upper reaches of Yao Yao Reservoir. The leaked crude oil spread downstream along the Xing Zi River, causing some rivers in Jingbian County of Yulin and Zhidan County of Yan 'an to be polluted. The polluted rivers in Jingbian County are 8 kilometers long.

Although the crude oil was intercepted at a distance of 0/5 km from Yao Yao Reservoir/KLOC-0, the accident also caused the water surface at the tail of Yao Yao Reservoir to be polluted, and the water supply in Yan 'an City was interrupted for three months. Yan' an city had to start the emergency plan for urban water supply and take water from Hongzhuang Reservoir, Xichuan River and Shenjing.

In fact, since Yao Yao Reservoir became the key water source in Yan 'an, as early as 2002, the Yan 'an municipal government approved the plan for the delineation of drinking water source protection areas. In this plan, the first-class water source protection area is 40 square kilometers, and the second-class protection area is 149 square kilometers. 102 all the oil wells stopped production in the first-class protection zone, but in the second-class protection zone, the requirements for oil well leakage prevention measures are more stringent.

However, crude oil pollution is still a big threat to the water quality of Yao Yao Reservoir. Strict protection measures have been taken in the regular oilfield, and the Yan 'an Joint Law Enforcement Environmental Monitoring Brigade has been stationed in the upstream. However, these measures can not effectively stop the activities of stealing and selling crude oil, and the hidden danger of crude oil pollution in the reservoir still exists.

In order to ensure the quality of water supply in Yan 'an city, after the crude oil accident in 2007, Yao Yao Reservoir no longer directly supplied water to the city, but supplied water to Hongzhuang Reservoir downstream near Yan 'an city through water pipelines, and then this reservoir supplied water to Yan 'an city.

Once the reservoir area of Yao Yao Reservoir is polluted, the water transmission line will be cut off to prevent sewage from directly entering the municipal water supply network. At the same time, Hongzhuang Reservoir can play an emergency substitution role when Yao Yao Reservoir is polluted, and maintain water supply to the urban area so that Yao Yao Reservoir can be cleaned up.

"The water level reached an all-time high this year, and now the reservoir area stores about 3.9 million cubic meters of water." Kang Jianbing, deputy director of Hongzhuang Reservoir Management Office, told the reporter that the main operation mode of Hongzhuang Reservoir is regulation and storage, so as to prevent the water supply in Yan 'an from being guaranteed after there is no water or water pollution in Yao Yao.

However, although Hongzhuang Reservoir has a total storage capacity of more than 90 million cubic meters, there are only a few small rivers in its upper reaches, which basically can't serve as water storage, and it can only rely on water from Yao Yao Reservoir. This 3.9 million cubic meters of water can only support Yan 'an for two or three months.

3. Introduce Huang Jiyan.

In the case that the water supply from Yao Yao Reservoir to Yan 'an City is increasingly tight and the water quality is easily polluted by crude oil, Yan 'an City has turned its attention to the Yellow River water.

Zhao Qian 'an, director of Yan 'an Water Saving Office, told reporters that the rivers in Yan 'an have less annual precipitation and large evaporation. It is not enough to meet the future urban development only by relying on the water system in the region, and water needs to be transferred from the Yellow River.

Yan 'an has a population of nearly 500,000. According to the forecast of the World Bank, it will reach 700,000 cubic meters by 2030, and the corresponding water consumption will also increase to10.3 million cubic meters per day. The water supply capacity of Yan 'an City is close to the limit. If water is not diverted from the Yellow River, urban water use cannot be guaranteed.

At first, the water transfer plan formulated by Yan 'an City was to take water from the Yellow River10.799 billion cubic meters every year, and this plan has been approved by the Yellow River Committee. However, with the proposal of Yan 'an's strategy of "developing industry by diverting water", the Yellow River diversion should not only solve the domestic water consumption in Yan 'an and some northern counties, but also meet the industrial water consumption of Yanzi (Yanchang, Yanchuan and Zichang) energy and chemical clusters.

Based on this consideration, the later water intake index was set at 9 1.8 million cubic meters, which not only solved the domestic water consumption of more than 65,438+million people in Yan 'an urban area, Yanchuan, Zichang, Yanchang and Qingjian, but also provided water security for Yan 'an Economic and Technological Development Zone, Yongping Refinery and Zichang, Yanchuan and Yanchang industrial parks.

After the allocation of the new water consumption index, nearly 30 million cubic meters of water will be provided to Yan 'an urban area every year, which means that 80,000 cubic meters of water will be transferred from the Yellow River to Yan 'an every day. Because Yan 'an wants to cut mountains and build cities to build Yan 'an New District, the urban area of Yan 'an will be greatly increased in the future, and this new water supply is also to meet the needs of urban expansion.

In addition, the development of Yan 'an Economic and Technological Development Zone is also facing the constraints of water resources, and its subordinate Yaodian Industrial Park, Ansai Industrial Park and Ganquan Industrial Park are all short of water. Shi Yu, deputy director of Yan 'an Economic and Technological Development Zone, told reporters that the development of economic development zones still faces the difficulty of water shortage. Although there is no large-scale water consumption industry, the average daily water consumption is also considerable.

In Yaodian Industrial Park, on the one hand, supporting enterprises related to energy and chemical industry are introduced, on the other hand, light industrial enterprises are introduced as tourist souvenirs. There are 15 enterprises in the park, and Yan' an cigarette factory consumes the most water. According to Guo Limin, deputy director of the power workshop, the workshop consumes more than 300 yuan of water every day, mainly using steam for tobacco production.

In Yan 'an Economic and Technological Development Zone, because there are no large-scale energy-based enterprises, the water consumption is much less than that of Yan Yanzi in the north of Yan 'an and Fuluohuang in the south. Of course, under the restriction of water resources, this economic development zone is also adjusting its industrial structure and developing low-water consumption industries.

4. Looking forward to industrial restructuring

The fourth Party Congress of Yan 'an City put forward the development strategy of "culture leading and tourism driving", and made great efforts to build tourism while developing the pillar industries of energy and chemical industry, with a view to driving the development of the tertiary industry. In the planning of revitalizing the old revolutionary base areas in Shaanxi, Gansu and Ningxia, the development of tourism in northern Shaanxi is also advocated.

Yan 'an, as a revolutionary holy land, is rich in red tourism resources, but the local tourism industry has not been able to expand. Yan 'an's economy is too dependent on energy. Yao Yinliang, secretary of Yan 'an Municipal Party Committee, said, "The industrial structure is single, and the oil economy is ups and downs". "The carrier function and livability of serving the development of tourism are low, and there is still a big gap with Yan 'an as imagined by the people of the whole country. "

Under the situation that energy and chemical industry are dominant, Yan 'an economy urgently needs to find a new way out and realize walking on two legs. In addition to characteristic agriculture such as Luochuan Apple and Yanchuan Jujube, low-water consumption tourism has become the best path for Yan 'an's industrial transformation.

However, Yan 'an lacks other tourist attractions except red tourist attractions, and the tourism product structure is too single. Yan 'an, located in the hilly and gully region of the Loess Plateau, is one of the areas with the most serious soil erosion in the middle reaches of the Yellow River, accounting for 78% of the total land area, and there are thousands of valleys everywhere.

In recent years, under the policy of returning farmland to forests, the hills in Yan 'an have turned green again and the scenery has become beautiful. However, due to loose soil and sparse vegetation, the problem of soil erosion is still serious. In addition, because some enterprises resist the compensation fee for water and soil conservation with kerosene gas, the funding gap for water and soil conservation cannot be made up.

In Yan 'an, which is short of water, red tourist attractions have also suffered from water shortage. During the revolutionary period, the scene of "Gunyan River" is gone, and the waters at the intersection of Xiayan River and Nanchuan River in Baota shan are also blocked by rubber dams. Due to the high sediment concentration in the river caused by soil erosion, the Yanhe River looks muddy.

Relatively speaking, Hongzhuang Reservoir, which is not far from the urban area, has become a good place for people to travel, and a large area of farmhouse music has also developed nearby. However, this is not a good thing for reservoir managers. Kang Jianbing, deputy director of Hongzhuang Reservoir Management Office, told reporters that the increase of tourists threatened the safety of drinking water sources in Yan 'an.

Some local observers said that there were few places with mountains and water like Baota shan in Yan 'an, and the lack of water greatly reduced the landscape. Yan 'an also beautified and afforested the urban section of Yanhe River by speeding up the construction of Yanhe landscape project, and created urban waterscape.

In addition, Yan 'an plans to relocate administrative institutions, transform street landscapes and restore the historical features of the city through the "Old City Reconstruction" project. By then, some places along the Yanhe River will be demolished, the gatehouse will be rebuilt, and the face of Yan 'an ancient city will be restored.