Xiaoheijiang River in Lincang and Puer

Chinese Name:小黑江（临沧-普洱: 双江-沧源-澜沧）
English Name: Xiaoheijiang River in Lincang and Puer(Shuang, Cangyuan and Lancang Counties)

Xiaoheijiang River is located in the northwest of Puer County (now Ning'er County), originating from the areas of Dawangtiantou and Zhaojiashan in Zhenyuan County. It flows through Jinggu and serves as the boundary river between Jinggu and Ning'er Counties. Xiaoheijiang River, a tributary of the Lancang River, is 175 kilometers long. It originates from the western slopes of Bangma Mountain in Gengma Dai and Wa Autonomous County, Lincang City, with a drainage area of 5,776 square kilometers. Historically known as Lasa River, it forms the boundary river between Shuangjiang, Cangyuan, and Lancang counties, and after passing through Jinggu, it also serves as the boundary river between Jinggu and Ning'er Counties before finally merging with the Lancang River.

River Overview: The river flows southwest and, after joining with the Man Yao River, continues as the boundary river between Jinggu and Ning'er Counties before entering the Lancang River. In Ning'er County, it stretches 35 kilometers, with a maximum water surface width of 87.3 meters, a minimum of 71.4 meters, and an average width of 80.67 meters. The maximum water depth is 6 meters, and the average depth is 2.33 meters. The river traverses through high mountains with steep gradients, and some sections have swift currents. The riverbanks are covered with subtropical broadleaf forests and include bamboo forests, banyan trees, dragon blood trees, and tree ferns. It supports a diverse range of wildlife, including macaques, lazy monkeys, Fei's leaf monkeys, and peacocks.

Tributaries:

1. Mengtai River: Originates from the back mountains of Baha and flows east into Xiaoheijiang River. It is 15 kilometers long with a drainage area of 27.45 square kilometers and an average annual flow of 0.44 cubic meters per second.
2. Nanzhang River: Begins at Xianrenfang Poto and flows west into Xiaoheijiang River, characterized by deep canyons and steep slopes. It is 11 kilometers long with a drainage area of 32.18 square kilometers and an average annual flow of 0.61 cubic meters per second.
3. Cha River: Originates from the Damo Liangzi watershed, formed by the confluence of Mang'an and Mangjin Rivers. It flows west into Xiaoheijiang River, with a length of 11 kilometers and a drainage area of 32.18 square kilometers, with an average annual flow of 0.33 cubic meters per second.
4. Maming River: Starts from the back mountains of Xiaomameng and flows south into Xiaoheijiang River. It is 10 kilometers long with a drainage area of 30.09 square kilometers and an average annual flow of 0.29 cubic meters per second.
5. Bangbing River: Originates from the southern side of Daqingshan and flows south into Xiaoheijiang River. It is 16 kilometers long with a drainage area of 77.9 square kilometers and an average annual flow of 1.85 cubic meters per second. The river area experiences frequent human and livestock activity, deforestation, and soil erosion, with occasional mudslides.

Lincang City Xiaoheijiang River Irrigation Project: Located in the southwestern part of Yunnan Province, this irrigation area covers southern Lincang City and involves the Xiaoheijiang River basin, a first-level tributary of the Lancang River. It spans three counties, 13 townships, and three farms, including Mengdong, Yanshuai, Mengsheng, Mengjiao, Danjia, Nuoliang, Menglai, and Mengsheng Farms in Cangyuan Autonomous County; Mengku, Shahe, Mengmeng, Bangbing Farms, and Mengku Farms in Shuangjiang Autonomous County; and Sipai Mountain Township in Gengma Autonomous County. The irrigation area ranges in elevation from 600 to 1,640 meters, with a total planned area of about 209.8 million mu (approximately 139,866 hectares). The current cultivated land is 71,000 mu, with a planned irrigation area of 51,000 mu. The project includes the construction of two medium-sized reservoirs, Xianzhulin and Xianzhulin, and an expansion of the Jiucai Dam reservoir. The main infrastructure includes 391.4 kilometers of pipelines, with 264.4 kilometers of new pipelines and 127 kilometers of continued pipelines, and seven new pumping stations. The total investment is estimated at 4.6267 billion yuan.

Jinggu County Xiaoheijiang River Subtropical Rainforest Forest Park: Located at the southern foot of Wuliang Mountain, on the border between Jinggu County and Ning'er County, the subtropical rainforest area is characterized by diverse and mysterious landscapes with variable climates. The river flows through high mountains and subtropical broadleaf forests, with rich natural resources including bamboo forests, banyan trees, dragon blood trees, tree ferns, macaques, lazy monkeys, Fei's leaf monkeys, and peacocks. It is also a starting point for the ancient Tea Horse Road, featuring ancient tea gardens and thousand-year-old tea trees. The area is known for large wild animals, making it a challenging destination for self-driving tours.