The main stream of Xunhe River

The Xunhe River originates from Chang'an District of Xi'an, enters the mouth of Ningshan County in the southwest, gradually turns to the southeast, and is originally called the Xunhe River. It passes through Huangjin Township, joins the Dongchuan River in the southwest of Zhen'an, and passes through Huangjiawan , Nayue River on the right, passing through Chongjiagou, continuing Xiaoren River and Daren River; after entering Xunyang County, going southeast, at Lianghe Pass in Xiaohe Township, Nazaishui on the left, and Qianyou River south of Zhen'an City , then passes through Zhaowan to the south, then passes through Ganxi to the southeast, turns southwest to Xunyang County, flows northeast, wraps around the west, north and east sides of the city, and flows into the Han River in the southeast. The total length of Xunhe River is 218 kilometers, with a water catchment area of ??6,307 square kilometers, and an average drop rate of 2.9‰.

In Chang'an District, the source of Xunhe River is located in Gangounao on the southeast side of Maichailei at the southern foothills of Shagou Mountain in the middle section of Qinling Mountains. Its upper source is called Shagou River. Its main tributaries include Jianghe River, Yuehe River, etc., and it flows southwest Ningshan County.

In Ningshan County, the Xunhe River merges from all tributaries in Chang'an District into Jiangkou Town, and was originally called Xunhe River. It flows eastward through Jiangkou Town and Jinchuan Town (formerly Huanghuang Township and Xiaochuan Township). Jiawan flows into Zhenan County. From Shagouling to Pengjiawan, the total length of the river is 64.1 kilometers.

In Zhenan County, the Xunhe River is 74.4 kilometers long and belongs to the middle reaches of the river. It enters at Xiaochuankou and flows northwest to southeast. Passing through Zhengjiazhuang, Huangjiawan, Chongjiagoukou, Shagoukou, Chaiping, Donggua and other places, it enters Xunyang County at the entrance of Antgou. The larger tributaries in the territory include Dongchuan River, Yue River and Xiaoren River.

In Xunyang County, the entry point is Renhekou Township, Xunyang County, to Xiaohe Liangheguan, where the largest tributary Ganyou River is received, and continues to flow south, passing through Zhaowan Town (formerly Tangxing and Zhaowan , Hongyan Township), Ganxi Town (formerly Daling Township), Ganxi Town, Bailiu Town, and Chengguan Town, merge into the Han River at the southeast corner of Xunyang County. The total length is 218 kilometers and the drainage area is 6308 square kilometers. The main stream in Xunyang County is about 115 kilometers long and the drainage area is 1166.5 square kilometers. The water energy reserve is 76,400 kilowatts. In the upper reaches of Ningshan County, the terrain is high in the north and low in the south, high in the west and low in the east. The flow direction is from northwest to southeast, with steep upstream and gentle downstream, often forming river valleys. The entire river has a height difference of 2125 meters, with an average drop of 1.165%.

The river in Zhen'an County in the middle reaches has obvious downcutting effect. The main stream or tributaries form a typical "V" shaped valley, with the widest point of 190 meters and the narrowest point of 60 meters. There is a lot of sand gold on the bottom of the river, and it has been proven that only 1,999.44 kilograms of sand gold are found on the bottom of the river bed 8.6 kilometers from Bawangtan to Bauhinia City.

The downstream section from the entry point of Xunyang County to Lianghe Pass. The total length is 30 kilometers. The mountains on both sides are relatively gentle, the valley is open, and there are many beaches. The river channel ratio is between 1.5-1.8‰. The river width is about 20 meters in low water. There are no steep dams or falling water. The water depth is about 0.4-0.5 meters, the flow speed is about 1-1.5 meters/second, and the river bed is mostly composed of gravel. This section above Renhekou was renovated twice and opened to navigation to Chaiping, Zhen'an County between 1958 and 1959. The section from Renhekou to Liangheguan could be navigable all year round before 1970. The section from Liangheguan to Xunhekou. This section has a total length of 64 kilometers, with open valleys, gentle mountains, and straight river channels, with a specific gradient of 0.8-1.2‰. The dry river surface is 40-50 meters wide and the water depth is 0.7 meters. Before 1970, this section was navigable year-round.