Ganhe

Ganhe river is a tributary of Nenjiang River. It originates from the foot of Woqi mountain in the east of Daxinganling Mountains, with an altitude of 1197 meters. It flows from northwest to Southeast, passes through molidawadaor Autonomous Banner and Olunchun Autonomous Banner of Hulunbuir City, Inner Mongolia Autonomous Region, and converges into Nenjiang River near Nenjiang Town, Heilongjiang Province. The main tributaries are Keyi River, Jiwen River, gaxianbei nameless River, Ali River, quelle River, etc. The river is about 446 km long, with a drainage area of nearly 20000 square kilometers. Among the tributaries, Ali River originates from the south side of yilehuli mountain, with a length of 124 km and a drainage area of 2183 km2. Most of the Ganhe river basin is located in mountainous areas, with dense primeval forests and lush vegetation. Hulunbeier in Daxinganling is rich in specialty products and good water conservation conditions. The shape of Ganhe river basin is like a long belt with uniform width. The Ganhe river reaches above the mouth of Ali River, with high mountains, deep valleys and narrow valleys. The width of the valley is between 1000m and 1500m. In the section from the mouth of Ali River to Dayangshu, the height of the valley is slightly reduced, and the valley is widened, ranging from 3000m to 4000m. In the section from Dayangshu to Gegen, the valley is gentle, and the depth is reduced, ranging from 4000m to 5000m. In the section from Gegen River to liujiatun, the valley becomes very narrow, with a width of about 1000 meters. From the lower liujiatun reach, the River entered the alluvial plain, the river gradually widened, the flow rate of the river slowed down, and finally converged into Nenjiang River.

Ganhe

Ganhe river is a tributary of Nenjiang River. It originates from the foot of Woqi mountain in the east of Daxinganling Mountains, with an altitude of 1197 meters. It flows from northwest to Southeast, passes through Oroqen Autonomous Banner and molidawaddaur Autonomous Banner of Hulunbuir City, Inner Mongolia Autonomous Region, and converges into Nenjiang River near the junction of Heilongjiang and Inner Mongolia. The main tributaries are Keyi River, Jiwen River, gaxianbei nameless River, Ali River, quelle River, etc.

Main stream situation

Ganhe River, also known as Hanhe River, belongs to Nenjiang river system and is the main tributary of Nenjiang River. It originated in the west of Dabai mountain, the main peak of yilehuli mountain in Oroqen banner, Inner Mongolia Autonomous Banner. It flows through Oroqen Autonomous Banner, Jiagedaqi district and Molidawa Daur Autonomous Banner. The Nenjiang River is poured into the southeast of eerhe township of Molidawa Daur Autonomous Banner 7 kilometers away. The river is 490 kilometers long, 50-200 meters wide, 1-3 meters deep, with a drainage area of 19700 square kilometers and an average annual flow of 130 cubic meters per second. The main tributaries are Keyi River, Ali River, Jiwen River, quelle River, etc.

The slope of Ganhe Valley ranges from 20 ° to 40 ° and the valley bottom is 3-4 km wide. It is a trapezoidal or shallow trough valley. Along the right bank of the river, there are more Shilazi, the flow is faster, and the river is zigzag, S-shaped or Ω - shaped. It can be seen from time to time that there are many streams flowing into Ganhe River from both sides of the old river course and Niuhe lake. Water bubbles are scattered all over the river. There are many sand beaches and sand mouths, generally about 0.4 to 1.0 square kilometers. The biggest one is near Laodaokou, which is 2.5 kilometers long and about 500 meters wide. It is sandy pebbles. The concave bank of the river is eroded and collapsed to form soil bank, while the convex bank is silted by sand and pebble beach.

hydrographic features

The Ganhe river opened in the middle and late April and closed in the first and middle November. The ice age lasted for 5 to 6 months. The annual precipitation is about 500mm, mostly from June to August. According to the records of the hydrological station, the average annual water level is 98.24m, the highest flood level is 102.01m (measured on August 9, 1988), and the lowest water level is 97.56m (measured on April 4, 1988). The annual average discharge is 66.7 m3 / s, the maximum discharge is 3200 m2 / S (measured on August 9, 1988), and the minimum discharge is 0.43 m3 / S (measured on February 12, 1985). The average extreme value of salinity in water is 209 mg equivalent / L, and the maximum value is 260 mg equivalent / L (measured on July 20, 1983). From 1975 to 1984, the average value of total hardness of river water was 0.7 mg equivalent / L, and the maximum value was 1.03 mg equivalent / L (measured on February 16, 1976). The extreme value of pH is 7.0 and the maximum is 8.1 (measured on July 11, 1976).

natural disaster

In 1988, due to the appearance of El Nino phenomenon, the climate in most parts of the world was abnormal. Under the influence of El Nino, the Ganhe River Basin in Daxing'an Mountains rained heavily in early August. On August 7, the maximum rainfall was 61mm at Jiwen station, 121mm at Ali River Station and 83mm at Jiagedaqi station in the upper reaches of the Gan River, resulting in a sharp rise in the water level of the Gan River. At 4:00 p.m. on August 9, the largest flood peak arrived at Jiagedaqi station, with a maximum flow of 3200 cubic meters per second. The highest water level was 102.01 meters, exceeding the warning water level by 2.58 meters. Although the original design standard was 20-year flood, the Ganhe levee withstood the test of 50 year flood in 1986, it was vulnerable to the 100 year flood. The water level exceeded the dam height, and more than 100 meters of the dam was destroyed. Five square kilometers of residential areas in Shuguang street and Guangming Street were flooded, and about 40 square kilometers of fields in Baihua Township were soaked in water. 2487 households and 11636 people were affected, 5.4 kilometers of dams and 1.8 kilometers of roads were destroyed. The total yield of farmland was 1000 mu, 264 houses collapsed and 1538 houses were destroyed. The total economic loss was 23.4 million yuan.

From June 26 to 30, 1989, due to the concentrated precipitation, the Ganhe river flowed out of the channel and part of Henan Province was flooded. On July 21, the Ganhe river flowed out of the trough again, the highway in Henan Province was interrupted for seven days, and the farmland on both sides of the Ganhe river was almost out of production, second only to 1988.

Main tributaries

Keyi River, the main tributary of Gan River, originates from Beigou, kubuchun forest farm, yituli River Forestry Bureau, in Oroqen Autonomous Banner, east foot of Daxing'an Mountains. Its geographical coordinates are 122 ° 08'18 "E, 50 ° 35'28" n, altitude is 1030 M. the river is 79.2 km long, 0.65 m deep and 15.5 m wide, with a drainage area of 1358 square km, flow rate of 0.85 M / s and flow rate of 9.89 m3 / s The average runoff is 312 million cubic meters, the average River gradient is 1.9 ‰, and the annual icing period is about 5-6 months. From west to East, it flows through kubuchun forest farm, Yina forest farm, Keyihe Town, huoduqi forest farm, molenge forest farm, sotuhan forest farm and Ganhe Town, and flows into Ganhe River in the north of Ganxi village of Ganhe town. The main tributaries are huoduqi River and sotuhan river.

Ali River, the main tributary of Gan River, originates from the southwest foot of yilehuli in the northeast of Oroqen Autonomous Banner, with an altitude of 1162 meters. From north to south, it flows into Ganhe River 1 km southeast of Alihe Town, Oroqen Autonomous Banner. The length of the river is 106 km (124 km), the drainage area is 2150 km2 (2183 km2), and the average annual flow is 16.1 m3 / s. The natural fall is 415 meters. The theoretical reserves of hydropower are 17500 kilowatts. The main tributaries are zuoali River, Kaila River, devo River, douke River, kangka River, Hongqigou River, etc.

Kuiler River, the main tributary of Gan River, originates from the eastern foot of Daxinganling in the middle of Lunchun Autonomous Banner, with an altitude of 1142 meters. The river is 189 km long, with a drainage area of 4723 square kilometers. The average annual discharge is 28.1 m3 / s. The natural fall is 415 meters. Along the northern foot of zakeqi mountain, it flows southward and eastward, and flows into Ganhe River 13 kilometers southeast of kuilehe Town, Molidawa Daur Autonomous Banner.

Gagdaqi River, a northern tributary of Gan River, originates in the northern mountains. It flows through Changhong street in gagdaqi district and flows into Ganhe river at Shuguang street, with a total length of 195 km. The lower reaches of the river are relatively curved, and the water level rises sharply in case of rainstorm due to the influence of flood jacking of Ganhe river near the estuary. In order to prevent flooding and ensure the safety of people's lives and property, the people's Government of Jiagedaqi district has gradually strengthened and improved the flood control dam projects on both sides of Jiagedaqi river.

Ergeqi river is also one of the northern tributaries of Gan River. Originating in the northern mountains, the river is 54 km long and flows through Jiabei township. Ergeqi river flows into toudao River, Erdao River, Wuchagou River, kertie River, Wuchagou first spring and Wuchagou second spring respectively. After passing through Baoshan Village, Donggou village, Baihua livestock farm and ergeqi railway bridge in Baihua Township, it flows into Ganhe river. It is the second largest river running through the north and south of gagdaqi district.

Taletu River, which originates from the Northwest Mountain range, flows through Baihua Township and flows into Gan River after confluence with xiaomorke River, which originates from the western mountain range. It is one of the main tributaries of the Gan River.

In addition, the kurch River, which originates in the western mountains, near nongyang in the living section of jiatie, flows through the scientific research station and flows into the Gan River. There are also three Baolong springs in the east of ergeqi railway bridge in the south of the area and two Wuchagou springs in the west of jianen highway.

Governance and development

The original dam of Ganhe river was broken in 1983, and the main project was built in 1984. The old river course was changed, and the bend was cut and straightened. The construction of the original dam of Ganhe river has played a certain role in resisting floods and reducing water disasters. In 1986, the dam was built and raised to stop the once-in-50-year flood. one

Chinese PinYin : Gan He