Economic development of the Rhone River

The Longhe River passes through fertile plains and important areas of the Alps, and the Longhe River basin is one of the huge economic regions in Switzerland and France. Agriculture in the Longhe River Basin is mostly located in low-lying areas, plains and islands. In Valais, Switzerland, the long river has been dammed, the river channel has narrowed, and the surrounding plains have been drained and reclaimed. The French have done a lot of work on the Rhone River, especially in the tributaries of the Essele River (in [combine de savoie] and [〔gresivoudan〕] and the upper reaches of the Dilans River). River water is widely used for irrigation. Feed crops and livestock farming coexist with vineyards, orchards and vegetable cultivation; Kamal is famous for growing rice.

Large and small industries have spread all over the basin. The obvious industrial concentration is: aluminum factories and chemical plants in the valley, oil refineries in Lyon, and oil refineries and steel mills in Foces. The whole Longhe River, especially the downstream, has obvious hydropower production. There are a series of dam projects downstream, and more than half of the potential hydropower capacity of the whole river has been developed and utilized. Several nuclear power plants in France use river water for cooling.

The Dragon River has always attracted tourists. Since the mid-20th century, tourism has played an increasingly important role in regional economy. Recreational activities provided by various places-such as skiing and mountaineering in the Alps, visiting the historic city of Provence and riding horses in Camag-have played a very important role in people's love for the Dragon River.

Shipping, especially between Lyon and the Mediterranean, has been going on. Traditionally, the Longhe River has been a traffic corridor between the north and the south of France. Valle Valle de Valle has always played a similar role in Switzerland. With the construction of many railway and highway tunnels under mountain obstacles, the role of valleys as transportation routes is particularly obvious. The largest reconstruction of the Longhe River itself is in the reach between Lyon and the Mediterranean Sea: the shoals have been flooded by reservoirs caused by dams or bypassed by canals, and the original steep river surface has been transformed into a series of gentle reaches and shiplocks.

192 1 year, the French parliament passed a bill, approved various public organizations to comprehensively regulate the Rhone River, and established the Rhone River Company on May 27th. 1933. The company accepted the right to manage and develop the Rhone River in 1934, and made a comprehensive plan for the Rhone River basin from 1945.

According to the plan, there are 7 cascade hydropower stations in the upper reaches of the Rhone River and 12 cascade hydropower stations in the lower reaches of the Rhone River. The lower reaches of the Rhone River are divided into upper, middle and lower sections, with four, five and three steps respectively. These cascade hydropower stations have all been completed, with a total installed capacity of 3.08 million kilowatts and an annual power generation of 654.38+067 billion kWh. * * * Construction of 25 dams, of which 22 are movable dams; There are 0/93 sluices/kloc-0, with a width of 15 ~ 45 m and a height of 7 ~ 15 m; There are 20 power stations, of which 19 is a low-head power station. These power stations are equipped with 83 hydrogenerators, including 6 Francis hydrogenerators, 33 vertical paddle hydrogenerators and 44 bulb hydrogenerators.

All five steps in the middle lower reaches of the Rhone River were completed at 1968. In the 1970 s, it was transferred to the upper and lower stages. The remaining six steps in the upper reaches of the Rhone River were also completed in the 1980s.

Twenty-two hydropower stations with more than 65,438+10,000 kilowatts have been built on the tributaries, including 5 in Switzerland and 0/7 in France/KLOC, most of which were built in the 1950s and 1970s. There are 15 hydropower stations with water heads above 1000 m, of which 4 have water heads above1000 m. The total installed capacity of tributary hydropower station is 6.233 million kilowatts, and the power generation reaches 65.438+04.283 billion kWh. The tributary hydropower station bears the peak load in the power grid, and the mainstream hydropower station bears the base load.

The dams built on the tributaries of the Rhone River are all high dams, two of which are more than 200 meters high. The Great Dixon Gravity Dam with a dam height of 285 meters and the Mowazan hyperbolic arch dam with a dam height of 237 meters are both world-famous high dams. These reservoirs are all built in deep mountain valleys upstream of tributaries, and their storage capacity is not large. There are only three reservoirs with a storage capacity of more than 300 million cubic meters, the largest of which is the Xiebangsen Reservoir on Durance River, with 65.438+0.27 billion cubic meters, which is a famous earth dam in France. See the hydropower station map of the main stream and tributaries of the Rhone River.

Special development management mode

In the development of the main stream of the Rhone River, the French Rhone Company adopted special development methods in combination with the specific conditions of the river and achieved success.

Its main experience is:

(1) adopts low dam multi-stage development mode, which not only avoids excessive inundation loss, but also meets the requirements of power generation, shipping and irrigation. The Rhone Company plans the Rhone River by dividing it into several small steps. Establish barrage every 1 step. The dam is equipped with movable gates. The length of the reservoir formed by the dam is not large, so dikes are built on both sides of the reservoir to reduce floods. An aqueduct is built from the upstream of the dam and extends far to the downstream of the dam, and a hydropower station is arranged in the lower section of the aqueduct. A tailrace channel is excavated downstream of the hydropower station to connect with the downstream reservoir. Hydropower stations can make use of the natural drop of the river reach and the water level raised by the dam. The lock is arranged next to the hydropower station, so the diversion channel and tailrace channel are navigation channels. Arrange the irrigation diversion structure at a suitable position. Dikes are generally designed according to the once-in-a-thousand-year flood. The drainage ditch is arranged near the embankment to maintain the groundwater level suitable for crop growth. Set up flood diversion in suitable river reach, and at the same time use the original river capacity to detain flood and reduce flood peak. This arrangement can avoid the interference of sediment on shipping.

During the planning of the Rhone River, it was considered to build a reservoir with a capacity of several billion cubic meters in the upper reaches to reduce the flood peak and maintain the low water level of the river. However, this plan will occupy a lot of land. It is planned to build a high dam in Pieschedale Canyon, which is only 200 meters wide and 45 meters high. The backwater of the reservoir can directly reach the Genesia Reservoir, 45km upstream, with a water storage area of 1 .80km2 and annual power generation of1100 million kWh. Another dam is planned to be built in Vivie in the upper reaches of Dunzel Canyon, with a reservoir area of 860 square kilometers. We had to give up because of the huge losses caused by the flood. The high dam scheme can't control the flood of downstream tributaries. The maximum discharge of the Rhone estuary is 65,438+04,000m3/s, while the maximum discharge of the Dilans River, a tributary of the left bank, reaches 65,438+00,000m3/s ... The two banks of the Rhone River are densely populated, with about 2 million people, which is very rich. Therefore, the high dam and large reservoir scheme is abandoned in the planning, and the multi-stage low dam scheme is adopted to save cultivated land and reduce the loss of resettlement and inundation. It is planned to build only one large Ranesia reservoir on the main stream (dam height 104m, total storage capacity of 53 million cubic meters, effective storage capacity12 million cubic meters), and all the other steps will be built into low-head runoff power stations.

By adopting this development method, the land acquisition area has been greatly reduced, with the upper reaches of the Rhone River occupying 180 square kilometers and the lower reaches of the Rhone River reduced from 860 square kilometers to 77 square kilometers.

(2) The hydropower station chooses the bulb unit with the best performance. Among the more than 80 turbines installed in the hydropower station on the main stream of the Rhone River, 47 have adopted cross-axis bulb tubular units. The maximum unit capacity of light bulb unit is 46,000 kW, and the water head17m. The unit has been improved in many aspects, simplifying the structure, improving efficiency and shortening the installation time. Compared with the vertical shaft propeller unit, this unit can improve the efficiency 1% ~ 3%, and the energy recovery rate can reach 0.9 due to the adoption of linear expansion draft tube, while the elbow draft tube is within 0.75. Using horizontal axis bulb unit can save 20% of civil engineering investment and 15% of equipment investment. This radial hydropower station has a fast construction speed, and a cascade can be built in an average of more than two years. These hydropower stations have all been managed by computers, and control centers have been set up in Genosia Cascade in the upper reaches of the Rhone River and Shattonaf in the lower reaches of the Rhone River. The control center can receive the water level, flow and operation data of each station, and send instructions to each power station in time, which improves the operation safety and the utilization efficiency of water energy. It can generate more than 4% electricity during peak hours. Due to the automatic control of the lower reaches of the Rhone River, the staff of the power station is greatly reduced. In the past, each hydropower station needed 60 people, but now the total number of hydropower stations on the Lower Rhone River needs 150 people.

(3) Management mode of Rhone River. The Rhone Company was founded with a capital of 24 million francs. At the beginning, we sold electricity and rented port facilities, and the income was used for river regulation projects. Later, it developed into hydropower, renting out self-built ports, docks and land on both sides of the river, collecting water charges and freight charges, and operating sand and gravel resources in the river bed. For decades, it has managed and developed while basically balancing revenue and expenditure, so that the whole management and development of rivers can continue.

Rhone River Company has 800 employees, including more than 500 engineers and technicians. Mainly responsible for the comprehensive development of power generation, irrigation and shipping in the main stream of Rhone River. Now the mainstream development has been basically completed and entered the management stage. The French government has granted the management right to the company, but important matters still need government approval. The government has strict restrictions on the authorization of companies. The company has no jurisdiction over tributaries, water rights and water quality control. This restriction is not conducive to environmental protection, nor to the protection of water conservancy facilities and river banks. Now, the company has signed an agreement with the French Ministry of Environment, according to which the company will strengthen the environmental management of the Rhone River basin.

Comprehensive benefit of downstream development of Rhone River

(1) power generation. The main stream of France has built 1g cascade hydropower stations with a total installed capacity of 3.075 million kilowatts and an average annual power generation of1670 million kwh. It is equivalent to 5% of France's total power generation and 1/4 of hydropower generation.

(2) shipping. The 3 10 km long waterway in the lower reaches of the Rhone River has been channelized. The water surface of the reservoir area is more than 200 meters wide, and the water surface of the waterway is 100 meters wide. In dry season, the water depth generally exceeds 5 meters. At the junction of the reservoir tail and the canal head, proper dredging is carried out locally, which can meet the navigation requirements. Each step is equipped with a lock. The lock chamber is 12m wide and 195m long, and can pass1500t European tugboat and 3000-5000t pusher fleet. Ships can sail directly from the Mediterranean to Lyon, and the cargo volume of 1979 reached 5.5 million tons.

The waterway connecting the Mediterranean Sea and the North Sea through the Rhone River is also being gradually implemented. One route is to connect the Thorne River, a tributary of the Rhone River, with the Marne River, a tributary of the Seine River, so that the fleet can reach the English Channel from the Mediterranean via Lyon and Paris, and the other route is to communicate with the Rhine River through the Thorne River. The original old canal can only pass 300-ton barges, and there are 1 12 old locks on the 230-kilometer waterway. Now it is planned to replace it with a new 24-class lock, so that the water depth of the channel can reach 3 meters and it can pass through a 3,000-ton pusher fleet.

(3) irrigation. After the transformation, the town not only eliminated the large-scale flood disaster, but also diverted water from the Rhone River for irrigation, and the economic benefits were also very remarkable. For example, taking water from the upper reaches of the Bouquet River 100 m3/s will expand the irrigation area to 200,000 hectares (1977, the irrigation area was only 50,000 hectares). The largest water conservancy project is the languedoc project in the lower reaches of the Rhone River. The main canal of this project is from fulk in the upper reaches of Gar River to Bezier area, with a total length of1.75km.. Each branch canal introduces 75 cubic meters of water per second, which irrigates a large area of farmland in the basin. The planned irrigation area of Rhone River is 6.5438+0.3 million hectares, which has reached 400,000 hectares at present.

(4) flood control. 40,000 hectares of land are protected by floods, of which 28,000 hectares are fully protected, and floods occur once every 65,438+0,986,5438+0 years.

(5) environment. After nearly 20 years of observation, the development of the Rhone River has not caused serious adverse environmental impact, water temperature and chemical stratification, and the water temperature in the lower reaches of the river has risen very little. Benthic organisms decreased in a short time, especially in some river sections with reduced flow. Fish species have not changed much. Because of the existence of large areas of water, almost all of them are waterfowl. At present, fish ladders are being set up to overcome the difficulty of herring swimming back. In short, compared with the benefits brought by the development, the negative impact of the development of the Rhone River on the environment can be ignored.