Xihe

Xihe

Xihe River is a tributary on the right bank of Yuxi River. It is a plain river gradually formed in the process of encircling and connecting polders, which is basically parallel to the left bank of the Yangtze River and goes eastward. The drainage area of Xihe River is 2224 square kilometers (including 602 square kilometers of water from Huangpi Lake).

Among them, 509 square kilometers are mountainous areas, 791 square kilometers are hilly areas, 869 square kilometers are plain polder areas, and 55 square kilometers are lakes.

Channel formation

In history, Xihe River is the section from Qiaokou to bianjiaguai, which is hereinafter referred to as "Tianhe" or "Zhouhe". The downstream channel from makouzha to huangluohekou is a part of ancient ruxushui. The channel of Xihe River into the river is gradually moving from the upper reaches to the lower reaches, which is the characteristic of the evolution of its water system. The earliest entrances to the river were xin'anqiao and liujiadu. After the Ming Dynasty, some tributaries of Tongjiang River were enclosed in the dykes because of the combination of the dykes along the river. Because of the water level of Tongjiang River, the upper Tongjiang river mouth looked for a new outlet downstream

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During the Zhengde period of the Ming Dynasty (1506-1521), the river mouth of liujiadu was blocked; during the Wanli period (1573-1619), the river mouth of Xin'an bridge was blocked, and then the Doumen of Xin'an bridge was built in 1591. Therefore, the estuary of Xihe River moved to the middle and lower reaches, mainly through Nicha River and Nicha estuary, through magou River and Shentang River and into Yuxi River through Huangluo estuary. In 1873, the entrance of Nicha River and Shentang River were blocked. So far, only one outlet of Xihe River was left to enter Yuxi River through Huangluo River, which became a major tributary of Yuxi River.

General situation of main stream

The main stream starts from the gap and flows eastward to Hengshan and turns north to Huanggu, and then turns east to Huanggu; it passes right naguogong river of liangjiaba, right nagulong river of HuLong north and Yongan river of Xiangan town south; it reaches Fenghuang neck, which is connected to the river through Fenghuang neck sluice on the right bank. Fenghuang neck sluice was built in 1952 and mainly uses river water for irrigation and after flood The Yangtze River drainage generally does not play the role of flood discharge in flood season. The Xihe River flows eastward and then turns northeast to Wuwei County Changba, zuonahuadu River, and flows into Yuxi River through Tianqiao to huangluohekou.

The length of the channel is 108km from the gap to the Huangluo estuary. The upper mouth of the channel is 110m wide and the bottom is 45m wide, with a gradient of 1 / 70000. The polder fields on both sides are concentrated, with about 1 million mu of cultivated land. The river embankment is composed of polders, and the flood control standard is still low.

Xihe River is located in the east of the county. The water of Huangpi Lake flows eastward through the gap (another branch flows into baihuxinhe river through Hebei Province) and flows to Wuwei from yushuguai. It flows from Fenghuangjing to Wuwei and crosses Lujiang River and Wuwei County, with a total length of 46.3 km. The section from the gap on the North Bank of the upper section to yushuguai is the Lujiang River (formerly known as Qinglian River, also known as HuanChuan), which is 10 kilometers long; the section on Yingshui nunnery on the south bank is the Lujiang River, and its subordinate Wuwei. Its tributary, huangtun River, originates from the eastern foot of southeast Tianguang mountain and the north of Zhaiji mountain. There are shilichong, wangjiachong, huangyanchong and other streams flowing into huangtun river. From south to north, huangtun river flows into Xihe River through sanxiqiao and huangtunzhen to yingshuian. The main stream of huangtun river is 15.2km long, with a drainage area of 51.2km 2.

Xihe River originates from Huangpi lake and Baihu Lake in Lujiang County, turns from Yushu to Wuwei County, passes through Huanggu, Hemao, Shushan, Hongxiang, quantang, HuLong, Jinji, Desheng, Aiguo, Liudu, Xiang'an, Jixiang, Shenma, YAOGOU, Sanxi, Hongqiao, Guanzhen, Wucheng, Changba, Fenghe, zhouzha, Cangtou, Dougou, Tianqiao, Huangluo and other townships and towns, and joins Yuxi River from Huangluo estuary. Xihe River is located in the plain area, the flow is gentle, the upstream water surface is wide, the downstream is supported by the Yangtze River water, the water level rises sharply in case of rainstorm, and the small mountain Dyke Burst.

Basin characteristics

The total catchment area of Huangpi lake and Baihu Lake above the gap of Xihe River is 1138 square kilometers, most of which are hilly areas. The incoming water will flow down the Xihe River after being regulated and stored by the two lakes. From 1953 to 1960, Baihu lake was reclaimed, which reduced the storage capacity of the upper reaches of Xihe River. However, Zhaohe River, after dredging and regulation, communicated with Chaohu Lake from the gap and northeast to Mawei estuary. So far, the flood above the gap basically flows into Chaohu Lake through Zhaohe River, and the inflow area from Xihe River below the gap to Yuxi River is 1622 square kilometers.

hydrographic features

After liberation, the Xihe River was continuously renovated. The length of the renovated Xihe River in the county was 76.45 km, which was 19 km shorter than the original arc river. The width of the river bottom was 20-30 m, the elevation of the river bottom was 6-4 m, the maximum irrigation flow was 178 m3 / S, the maximum drainage flow was 300 m3 / s, the drainage area was 1746 square km, and the average annual runoff was 26.2 m3 / s. According to the data statistics of Wucheng hydrological station from 1954 to 1988, the highest water level of Xihe River was between 9 and 11 meters in 25 years; the highest water level was above 11 meters in 4 years (the highest water level was 13.02 meters on August 29, 1954); the highest water level was below 9 meters in 6 years (the highest water level was 8.40 meters on July 30, 1972). The lowest water level of Xihe River is about 6 meters in dry season.

Main tributaries

The West River runs through Wuwei County from west to East, enters Yuxi River, and then joins the Yangtze River. Its main tributaries are Hemao River, Guogong River, Yong'an River, Dushan River, Huaqiao River, Huadu River, HuangChen River, HuLong River, etc.

Hemao River: it originates from baixiling, flows into Xihe River from Fudu via Hemao Township, with a total length of 9 km, and dries up in winter and spring.

Guogong River: also known as Ganghe River, it starts from zhangsandu, Wangtian Township, flows through Zhenghe and Hongxiang Township, and ends at Zhongjia village. It is divided into two branches, one from Jiajian bridge, the other from gujiadu to Xihe River, with a total length of 14 km, a drainage area of 121 square km, and an average annual runoff of 1.8 m3 / s.

Yongan River: it originates from Yanqiao mountain area, flows through Xugang, Gulou, Shangli, Yangshan, Xidu, Xianfeng, Baoshan, Jinji, Desheng, Xiang'an and other villages and towns to Xihe River, with a total length of 27.5km, a drainage area of 376km2 and an average annual runoff of 5.6m3/s.

Dushan River: from panjiaqiao in Shangli township to erlibandon in Xidu township to Yong'an River, with a total length of 10.5km, a drainage area of 82km2 and an average annual runoff of 1.3m3/s.

Huaqiao River: it starts from Huaqiao, Guanhe Township, passes through Liudian, Xidu, Jianguo and Baoshan townships, and enters Yong'an River from jiandanzui, with a total length of 10.5km, a drainage area of 76km2 and an average annual runoff of 1.2m3/s.

Huadu River: starting from Weijiaqiao in Fulu Township, it flows into Xihe River through Hongmiao, Honglin, tanshu, Hedian, Hongqiao, Guanzhen, Wucheng and other townships, with a total length of 20.5km, a drainage area of 246km2, and an average annual runoff of 3.7m3/s (xinhuadu river was dug in 1974, and it flows into Xihe River from Huadu gate to shangsanxikou, with a total length of 4.3km).

HuLong River: it starts from Daijia ferry of Xihe River in the north and ends at Paifang village of Tuqiao in the south, with a total length of about 19 kilometers. It flows through daijiadu, Hualin, Doumen town of HuLong, Nanzhuang, Lijiazhuang, hujiaqiao, Zhangjiazui, cetoudai, shanhouchen, xiaopeijia, xin'anqiao, Paifang Village, etc. It belongs to the north-south river, which is the earliest channel into the West River.

water conservancy project

River regulation

From 1736 to 1795, a new river was excavated to connect the upper and lower sections of the Xihe River. Later, a new river was opened to discharge water from Huangpi lake, Baihu lake and Wuwei southwest rivers into the Yangtze River through Nicha and Yuxi. From 1821 to 1850, shenjiawei and lianhewei were built on both sides of Huangpi lake. From 1862 to 1874, tianjingwei and sujiawei were built. In 1825, Liu Yongtian, the Wuwei Zhizhou Prefecture, opened a new fenghuangjinghe River, about 5 li long. The water from the upper reaches of the river flowed into the river through yaojiagou. Dams were built at both ends of the new river, and the river was abandoned. In order to meet the needs of flood discharge in flood season and water diversion irrigation in dry season, Fenghuang neck sluice was built at the entrance of Xihe River in June 1953, with two holes in total. Each hole has a clear width of 5.6 meters, a bottom height of 5 meters, a clear height of 4 meters, a bottom height of 9 meters of parapet, a reinforced concrete structure, a maximum drainage flow of 112 cubic meters per second, a drainage benefit of 4.27 million mu and an irrigation benefit of 1.31 million mu. After the completion of Yuxi sluice in 1972, the Xihe River could not be discharged when the water level of the Yangtze River was high, which made the drainage difficult. In 1987, the first stage of Xihe river regulation project was started. It was treated as a small section, with a discharge of 300-350 cubic meters per second, a river bottom elevation of 4-3 meters, a bottom width of 55 meters, and a dike top elevation of 13-13.5 meters.

Irrigation engineering

In 1978, there was a severe drought, and there was no rain for more than 200 days in Chaohu basin. The water level of Chaohu Lake dropped to 6.58 meters, and the water source was extremely short. A station was temporarily built on the Bund of the Yangtze River at Fenghuang neck in Wuwei County to irrigate Chaohu Lake through the West River. In order to speed up the management of Chaohu Lake Basin, Anhui Provincial Revolutionary Committee requested the Ministry of water and electricity to approve the construction of fenghuangjingjiang irrigation project in May 1979. In the spring of 1985, the State Council agreed to include the Fenghuangjing hub project in the Pishihang Chaohu project, and to use world bank loans to cooperate with domestic funds for construction. In 1986, the Fenghuangjing junction project broke ground at liujiadu, the upstream of Fenghuangjing old sluice. The project is a comprehensive utilization project combining pumping irrigation, pumping drainage, self diversion and self drainage. The pumping station adopts double water pump

Chinese PinYin : Xi He