Wumen Weir

　　Wumen Weir, located 15 kilometers north of Chenggu County in the eastern part of Juyuan Town on the west bank of the ?? River, is named for its five parallel inlets at the head of the irrigation channel. “Wumen Weir was first built in the second year of the Jushè era of the Western Han Dynasty (7 AD),” boasting a history of over two thousand years. It remains well-preserved to this day and continues to function effectively. In 1984, the Wumen Weir Cultural Relics Management Office was established. In 1992, it was designated as a Shaanxi Provincial Cultural Relics Protection Unit by the Shaanxi Provincial People’s Government. In May 2006, it was announced as a Major Historical and Cultural Site Protected at the National Level by the State Council.

　　The Wumen Weir project is grand in scale and magnificent in architecture. The river-blocking dam is 374 meters long, 1.2 meters high, with a 2.5-meter-wide top platform and 15-meter-wide slopes. About 500 meters downstream from the five inlets at the head of the weir, there are two inlet floodgates and four outlet floodgates, which can control water flow. The design is scientifically sound and bears resemblance to the architectural style of the Dujiangyan Irrigation System in Sichuan. The main canal is 8.9 kilometers long, with an inflow of 2.5 cubic meters per second, currently irrigating over 7,300 acres of farmland.

　　The initial construction of Wumen Weir was very rudimentary. According to the “Wumen Weir Stele Inscription,” from the Han Dynasty to the Northern Song Dynasty, due to obstruction by the Dou Mountain stone spur, water did not reach the lower dam and only irrigated several hundred acres of farmland upstream. By the Shaoxing era of the Southern Song Dynasty (1131–1162 AD), County Magistrate Xue Keguang (from Hedong), expanded Wumen Weir. At the Dou Mountain stone spur, he “built wooden troughs to divert water, allowing it to flow downstream,” thus extending irrigation to “three thousand fields.”

　　In the seventh year of the Zhiyuan era of the Yuan Dynasty (1347 AD), County Magistrate Pu Yong (from Yanzhou, Shaanxi), mobilized the people of the irrigated area and personally led the reconstruction of Wumen Weir. He “rebuilt the five inlets and reconstructed the stone canal,” using the method of “burning and water hammering” to “chisel through the rocky gorge behind Dou Mountain to create a water passage, irrigating 40,840-plus acres of farmland and powering seventy mills.” This not only expanded the irrigated area but also developed agricultural and sideline production. “The people benefited greatly and erected a memorial shrine for (Pu Yong) on Dou Mountain in his honor.”

　　During the Hongzhi and Wanli eras of the Ming Dynasty, three large-scale renovations and expansions greatly increased the effectiveness of Wumen Weir. According to the “Wumen Weir Stele Inscription”: In the fifth year of the Hongzhi era (1492 AD), Chenggu County Magistrate Hao Sheng (from Licheng, Shandong), presided over reopening the Dou Mountain stone canal, “digging it two zhang deep and twice as wide,” significantly increasing water volume. From the third to the seventh year of the Wanli era (1575–1579 AD), County Magistrate Qiao Qifeng (from Anyi, Shandong), expanded Wumen Weir, “creating various inlet and spillway gates and allocating water according to land area,” referring to the scientifically designed proportional water management system of the current “dou” and “sheng” gates, which is still in use today. From the 23rd to the 26th year of the Wanli era (1595–1598 AD), County Magistrate Gao Dengming (from Yicheng, Shanxi), “personally donated his salary, replacing wood with stone,” and oversaw further construction of Wumen Weir. By then, the Wumen Weir irrigation system was largely completed, with “a total of 36 water-dividing inlets and spillways, irrigating over 50,000 acres of farmland,” making it the largest among the weirs of Chenggu.

　　The completion of the Wumen Weir irrigation project led to rapid agricultural development in Chenggu and brought great benefits to the people. Grateful for the advantages it provided, later generations built shrines for Magistrates Qiao and Gao at Wumen Weir, erected steles and biographies, and placed their statues in the Yuji Hall of Wumen Weir, where they are worshipped by descendants. An annual commemorative gathering is held on the 24th day of the sixth lunar month.

　　Wumen Weir has a rich cultural and historical heritage. According to the Wumen Weir steles and the “Chenggu County Annals,” many notable figures throughout history have contributed to the weir’s construction. Notable historical contributors include: Xue Keguang of the Song Dynasty; Pu Yong of the Yuan Dynasty; Hao Sheng, Qiao Qifeng, and Gao Dengming of the Ming Dynasty; Mao Jike, Hu Yijun, Yu Fengchen, Fuming’a, Xiao Hanqing, Zhang Kejian, Zhou Yaodong, and Zhang Shiying of the Qing Dynasty. During the Republican era and after the founding of the People’s Republic, three generals, two provincial governors, and two water conservancy experts visited Wumen Weir for inspection. For example, in 1931, General Yang Hucheng inspected the site; in 1933, his subordinate, Brigadier Zhao Shoushan; in 1934, General Sun Weiru; and in 1940, Chen Daqing, Commander of the 29th Army, 31st Group Army of the Nationalist Party. In 1932, modern water conservancy expert Li Yizhi and in 1942, engineer Liu Zhongrui (later the Director of the Shaanxi Water Conservancy Department) also inspected Wumen Weir.

　　With its long history, scientifically rational engineering, and significant effectiveness, Wumen Weir has received continuous attention and protection from successive dynasties’ governments and local people, ensuring its endurance through the ages.

　　Wumen Weir features an ancient temple called Longmen Temple, consisting of three courtyards and four halls. It includes over thirty Ming and Qing dynasty structures such as the Grand Buddha Hall, Yuji Hall, Taibai Tower, Guanyin Pavilion, River-Watching Tower, stele pavilion, and official quarters, historically serving as the office for Wumen Weir management. It now houses the Chenggu County Wumen Weir Cultural Relics Management Office and the Wumen Weir Water Management Station.

　　After the founding of the People’s Republic of China, the Communist Party and government placed great importance on this ancient irrigation project, mobilizing local communities for repairs. Later, the state allocated multiple funds for renovation and restoration, revitalizing the ancient weir, restoring its functionality, and ensuring the proper preservation of its historic architecture. Scattered cultural relics were also recovered, displayed, and protected. A stele corridor was built, and the site now preserves over forty historical hydrological steles, forming a precious collection of historical documents for studying ancient water conservancy engineering and management. In June 2006, Wumen Weir was announced as a Major Historical and Cultural Site Protected at the National Level by the State Council.