How big is Qiantang River?

Qiantang River is one of the main rivers in the southeast coastal area of China and the largest river in Zhejiang Province. Because the river winds zigzag near Hangzhou, it is also called Jiang, Qujiang and Zhejiang.

Qiantang River originates from Qingzhidaijian, Xiuning County, Anhui Province, and reaches Zhakou River in Hangzhou, with a length of 484km (2 16.5km in Zhejiang Province). The basin covers an area of about 42,200 square kilometers, including about 35,600 square kilometers in Zhejiang Province, and the rest belong to Anhui, Fujian and Jiangxi provinces. The main tributaries of Qiantang River are Wuxi River, Jinhua River, Xin 'anjiang River, Fenshui River and Puyang River. Various parts of the mainstream have different names everywhere. From the source to Quzhou, Jiangshan Port and Wuxi River meet together and are called Qujiang River. To Lanxi City, Jinhua River flows in, which is called Lanjiang River. Zhimeicheng meets Xin 'anjiang, the main tributary, and becomes the main stream, which is called Tongjiang. Tonglu is hereinafter referred to as Fuchunjiang; Below Wenjiayan is called Qiantang River. The average annual runoff of Qiantang River for many years is 40.4 billion m3, with little sediment concentration, averaging 5‰.

Water system composition

Qiantang River twists and turns, and the upstream is a mountain stream. Beam-to-beam alternation; The middle reaches are hills; The downstream estuary is trumpet-shaped, and the estuary gradually widens. The main tributaries are Wuxi River, Wujiang River, Xin 'anjiang River, Fenshui River, Puyangting River and Caoejiang River.

(1) Wuxi River: Originated in the eastern mountainous area of Pucheng County, Fujian Province. East flows through the northwest of Longquan County, Zhejiang Province, and joins Qujiang River in Zhangtan Town, Quxian County. The total length of runoff 150km, and the drainage area is 2590km2. The average annual runoff for many years is 3.076 billion m3. The natural drop is 802m, and the theoretical reserve of water energy is 183800 kW. Rivers develop, and the main tributaries are Zhougongyuan and Hushan.

(2) Xin 'anjiang; Originated in the southern foot of Huangshan Mountain in Anhui Province. Southwest flows through Shexian County and Xiuning County, and is named Xin 'anjiang River after meeting in Linxi Town of Huangshan City. The winding southeast flows to the east. It passes through the southern border of Anhui Province, Chun 'an County of Zhejiang Province and other counties, passes through Xin 'anjiang Reservoir, passes through the southwest of jiande city City, and flows into the Lanjiang River system to the east of Meicheng Town. The east flow is called Fuchunjiang River. The total length of the main stream is 26 1km, and the drainage area is 1 1772km2. The average annual flow in Anhui Province is 166m3/s, and the total natural drop is 1240m. The theoretical reserve of hydropower is 552,000 kilowatts. The main tributaries are Shouchangjiang River, Dongyuan River, Fengle River, Wuqiangxi River, Changxi River and Xiuning River. Xin 'anjiang is a perennial river with small sediment concentration and clear bottom. Before the completion of Xin 'anjiang Hydropower Station, the river bed gradient was large, and there were many canyons and shoals along the river. After the power station is completed, A Xin Anjiang Reservoir (also known as Qiandao Lake) with an area of 580 square kilometers will be formed under Zijin Beach. After the completion of Fuchunjiang Hydropower Station, the backwater of Fuchunjiang Reservoir has reached Yangxi. The water level in Meicheng is stable between 22-23 and 5m. The rapids below Zijin Beach have disappeared, and 50t freighters and 200 passenger ships can reach Baisha from Meicheng. The flood is controlled by the regulation and storage of Xin 'anjiang Hydropower Station, with the maximum discharge of13200m3/s. ..

(3) Puyang River: It originates from Dayuan Bay in Pujiang County, flows through the north of Shaoxing in Zhuji City, and joins Qiantang River near Yan Wen Town in Xiaoshan City. The total length is 50 kilometers. The drainage area is 343 1km2. The average annual runoff for many years is 2.46 billion m3. The upstream river is 22-75m wide and the downstream river is 80- 120m wide. The main tributaries are Chen Jiang, Hua Kai and Qiao Feng. There are small and medium-sized reservoirs such as Anhua, Qingshan and Shibi in the upper reaches 1037. The total storage capacity is 3 1 10000 m3; There is a high lake flood diversion gate in the middle reaches; Downstream cutting and straightening, excavation of new rivers, irrigation area of 230,000 mu.

(4) Wujiang: also known as Jinhua River and Youxi. Shangyuan River is formed by the confluence of Dongyang River and Wuyi River into Jinhua City. The main stream flows northeast along the boundary (boundary river) between Jinhua City and Wuyi County, and joins Lanjiang River in the northwest suburb of Lanxi City. Liu Yu is 33 kilometers long. The total length from the source is 179km, the drainage area is 655 1km2, the annual average flow is 153.4m3/s, and the annual runoff is 5.3 billion m3. The natural drop is 458m, and the theoretical reserve of water energy is 23,700 kW. It is possible to develop an installed capacity of 37,500 kW.

(5) Fenshui River: The main source is Tianmu River, which originates from the mountainous area near Jingzhou, Jixi County, Anhui Province and flows eastward into Lin 'an County, Zhejiang Province through Tianmu Mountain Canyon. The main channel turns south, and the flow direction is Danxi. Nanhui Bukou Creek, crossing Changhua Town, is called Tianri Creek. In Tonglu County, the name of Fenshui River began. It flows into Fuchun River in the south, with a total length of 174km, of which the length in Anhui Province is 1 1.6 km, with a total drainage area of 3430km3. The average annual runoff for many years is 365,438+300 million m3. Natural fall 1 142m. Theoretical reserves of hydropower) 0.7 million kilowatts. Two hydropower stations have been built in the basin with a total installed capacity of 7500 kilowatts. The main tributaries are Baduxi and Eleven Xi Du.

(6) Cao 'e River: It originates from Tiantai Mountain in the south of Shandong Province, in the east of Pan 'an County, passes through the northwest of Xinchang County to Shengxian County, accepts tributaries on the left and right banks, and then passes through Shangyu County to Hangzhou Bay, a native of Shaoxing City. Total length 192km, with a drainage area of 5922km2. The average annual runoff for many years is 4.53 billion m3. The natural drop is 5 15m. Theoretical reserve of hydropower196,000 kilowatts. The basin is mountainous and the water system is developed. The main tributaries are Xinchang River, Changle River, Xiaoshunjiang River and Huangzejiang River.

Natural characteristics of river basin

Qiantang River Basin is adjacent to the southeast coast of China, located in the subtropical monsoon climate zone, with an annual average temperature of 17C. The northwest wind prevails in winter, and the weather is sunny, cold and dry. In summer, there are many southeast winds, high temperature, strong light and humid air; Cyclone activity is frequent in spring and autumn, and the temperature changes greatly. There are many frontal rains in spring and early summer, and many typhoons in summer and autumn. The direction of monsoon circulation is basically orthogonal to the direction of the main mountains, and the mountains play a role in blocking the cold current and typhoon in the north. The annual average precipitation is 1600mm, in which it is rainy from April to June, accounting for 50%, which is prone to floods. July-September accounts for 20%, with frequent disasters in the early stage. River runoff changes greatly during and between years. For example, the ratio of measured annual runoff at Tibu Station on Fuchunjiang Road (control area 3 1700km2) is 5: 1.