Nierji reservoir

Nierji water control project

synonym

Nierji reservoir generally refers to Nierji water control project

Nierji water control project is located on the main stream of Nenjiang River at the junction of Heilongjiang Province and Inner Mongolia Autonomous Region. On the right bank of the dam site is Nierji Town, moridawa Daur Autonomous Banner, Inner Mongolia Autonomous Region, and on the left bank is erkeqian Town, Nehe City, Heilongjiang Province. It is about 189 km away from Qiqihar City, an important industrial town downstream. The total construction period of Nierji water control project is 5 years, and the construction began on June 1, 2001. The first stage is the diversion of the left bank open channel, and the second stage is the diversion of the temporary bottom outlet of the powerhouse erection bay dam section. The first phase of river closure was realized on November 8, 2001, and the second phase was realized on September 15, 2004. On September 11, 2005, the sluice was lowered to store water. On July 16, 2006, the first unit was connected to the grid for power generation. The main project was completed by the end of December 2006.

Nierji water control project is the first phase project recommended in the "comprehensive development and utilization plan of water resources in Songhua River and Liaohe River Basin" approved by the State Council in 1994. It is a key project of the Tenth Five Year Plan and one of the landmark projects of the "western development strategy" implemented by the state. Nierji water control project is not only a disaster reduction project, but also a water source project of three provinces in Northeast China. It is a large-scale control project mainly for flood control, urban living, industrial and agricultural water supply, combined with power generation, improving downstream shipping and water environment, and creating conditions for optimal allocation of water resources in Songliao region.

Nierji water control project has a normal pool level of 216.00 meters, a check flood level of 219.90 meters, a design flood level of 218.15 meters, a flood control high water level of 218.15 meters, a flood season limited water level of 213.37 meters, and a dead water level of 195.00 meters. The total reservoir capacity is 8.61 billion cubic meters, including a flood control capacity of 2.368 billion cubic meters, a profit making capacity of 5.968 billion cubic meters, a total installed capacity of 250000 kilowatts, and an average annual power generation of 638.7 million kilowatts .

geographical position

Nierji water control project is located on the main stream of Nenjiang River at the junction of Heilongjiang Province and Inner Mongolia Autonomous Region. On the right bank of the dam site is Nierji Town, moridawa Daur Autonomous Banner, Inner Mongolia Autonomous Region, and on the left bank is erkeqian Town, Nehe City, Heilongjiang Province. It is about 189 km away from Qiqihar City, an important industrial town downstream. Nenjiang River originates from yilehuli mountain in Daxing'an Mountains, flows through Heilongjiang, Inner Mongolia and Jilin provinces (autonomous regions) from north to south, and flows into Songhua River in Sancha River of Zhaoyuan County, Heilongjiang Province. The total length of Nenjiang River is 1370 km, and the drainage area is 297000 square kilometers. The dam site of Nierji water control project is located in the last gorge of the main stream of Nenjiang River, which chokes the throat of Nenjiang river flowing into the vast Songnen Plain from mountainous and hilly areas. The controlled drainage area above the dam site is 66400 square kilometers, accounting for 22.4% of the total area of Nenjiang River Basin. The average annual runoff is 10.47 billion cubic meters, accounting for 45.7% of Nenjiang River Basin.

Scale benefit

Nierji water control project is a large-scale control project, which mainly focuses on flood control, urban living, industrial and agricultural water supply, combines power generation, improves downstream shipping and water environment, and creates conditions for optimal allocation of water resources in Songliao region.

Nierji water control project has a normal pool level of 216.00 meters, a check flood level of 219.90 meters, a design flood level of 218.15 meters, a flood control high water level of 218.15 meters, a flood season limited water level of 213.37 meters, and a dead water level of 195.00 meters. The total reservoir capacity is 8.61 billion cubic meters, including a flood control capacity of 2.368 billion cubic meters, a profit making capacity of 5.968 billion cubic meters, a total installed capacity of 250000 kilowatts, and an average annual power generation of 638.7 million kilowatts .

(1) Flood control

After the completion of the project, the flood control standard of Qiqihar city will be increased from once in 50 years to once in 100 years, the flood control standard of the section from the junction to Qiqihar will be increased from once in 20 years to once in 50 years, and the flood control standard of the section from below Qiqihar to Dalai will be increased from once in 35 years to once in 50 years.

(2) Industrial and agricultural water supply and wetland protection

In the design level year, the reservoir will supply 1.029 billion cubic meters of water for urban life and industry, 1.646 billion cubic meters of water for agricultural irrigation, which will increase the downstream irrigation area to 4.54 million mu, and 328 million cubic meters of water for wetland to maintain and restore the wetland area and improve the ecological environment.

(3) Power generation

The installed capacity of Nierji hydropower station is 250MW, and it can bear 180MW peak regulation capacity at the maximum load, accounting for 3.5% of the system peak regulation capacity and 9.8% of the hydropower peak regulation capacity. It will play an important role in increasing the peak regulation capacity of Heilongjiang power grid, alleviating the shortage of peak regulation capacity and the serious imbalance of the proportion of hydro thermal power.

(4) Shipping

Songhua River waterway is an important transportation line for transporting coal from east to west, import and export to the Far East of Russia. With the increase of upstream industrial and agricultural water consumption, the inner diameter flow of the river will decrease. After the completion of Nierji water control project, the annual average water supply for shipping is 820 million cubic meters, which can increase the shipping flow of Harbin control section guarantee rate from 201 cubic meters per second to 550 cubic meters per second To create favorable conditions for the development of river shipping.

(5) Water environment protection

Qiqihar section of Nenjiang River and Harbin section of Songhua River are the main polluted areas in Songhua River Basin. The river water is polluted by various pollutants, especially in dry season. It is necessary to maintain a certain flow rate while taking sewage treatment measures to alleviate water pollution. After the completion of Nierji water control project, the design level year can provide 475 million cubic meters of compensation water for the downstream of the reservoir, so that the discharge of Qiqihar river section is not less than 35 cubic meters per second, and that of Harbin river section is not less than 250 cubic meters per second.

Project composition

Nierji water control project is mainly composed of main dam, auxiliary dam, spillway, powerhouse of hydropower station and irrigation tunnel (pipe). The engineering grade is first-class, the main buildings are grade I, and the seismic fortification intensity is grade VII. The total length of the dam is 7265.553m, the maximum dam height is 40.55m, and the crest elevation is 221.00m. The standard of normal operation flood is once in a thousand years (15000 m3 / s), and the standard of abnormal operation flood is the maximum possible flood (24900 m3 / s).

(1) Main dam

The main dam is built in the main river bed, with a total length of 1807.31 meters (including 149 meters of the power plant), a foundation elevation of 180.3-186.5 meters, a crest elevation of 221.00 meters, and a maximum dam height of 40.55 meters. The dam crest is 8m wide, the upstream and downstream dam slopes are grade II slopes, the berm elevation is 205.00m, and the berm width is 3.55m. The upstream dam slope is 1:2.2, and the downstream dam slope is 1:1.9 and 1:2 respectively. The upstream dam face adopts concrete slope protection, the downstream dam face adopts gravel slope protection, and the downstream dam site is provided with slope drainage body. The non open channel section of the main dam is a gravel dam with roller compacted asphalt concrete core; the diversion open channel section is a roller compacted asphalt concrete rockfill dam, and the right end of the main dam is connected with the powerhouse through a concrete wing wall, with a 79.80m long rockfill transition dam section. Below the core wall of the main dam, as the dam foundation is located on the sand gravel layer with medium strong permeability and the sand gravel layer with mud, the 0.8m thick concrete cutoff wall is adopted for the dam foundation.

(2) Left auxiliary dam

The left auxiliary dam is a sand gravel dam with clay core, which is built on the second-order erosion accumulation terrace on the left bank. The length of the dam is 1459.29 meters, the maximum height of the dam is 23.00 meters, the elevation of the dam crest is 221.00 meters, and the width of the dam crest is 8 meters. The first grade slope is adopted for both upstream and downstream, and the slope ratio is 1:2.75. The center line of the clay core wall is located at the upstream of the dam axis, 2m away from the dam axis, 3M wide at the top, and the downstream slope ratio is 1:0.2.

(3) Right auxiliary dam

The right auxiliary dam, built on the platform of Baitushan on the right bank, is a sand gravel dam with clay core. The length of the dam is 3998.953m, the maximum height of the dam is 15.50m, and the width of the dam crest is 8m. The upstream and downstream slopes are all grade I slopes with the slope ratio of 1:2.8. The center line of the clay core wall is located at the upstream of the dam axis, 2 meters away from the dam axis. Horizontal and vertical filters are set downstream of the core wall.

(4) Spillway

The spillway is an open bank slope spillway. The spillway project is located on the platform of Baitushan on the right bank and crosses the right auxiliary dam. The total width of the overflow front edge is 166 meters and the longitudinal length is 875 meters. The overflow weir surface adopts Wes curve. The crest elevation of the weir is 199.8 meters. There are 11 holes in total and the net width of a single hole is 12 meters. Differential underflow energy dissipation is adopted. It mainly includes diversion channel, control section, chute section, stilling basin, apron section and tailrace section. Design discharge: 14227 m3 / s, check discharge: 20300 m3 / s.

(5) Powerhouse of hydropower station

The hydropower station is a river bed type power station. The size of the generator room is 149 × 26.1 × 60.64m. Four zza833-lh-640 hydro generator units are installed with a unit capacity of 62.5mw. Two sfp9-150000 / 220 main transformers with output voltage of 220kV are installed.

(6) Left bank irrigation pipe

The irrigation pipe structure on the left bank consists of water intake section, irrigation pipe section in front of gate, well section of gate and irrigation pipe section behind gate

Chinese PinYin : Ni Er Ji Shui Ku