Changtai Longjin Weirs, China

The Changtai Longjin Weirs irrigation system, located in Changtai District, Zhangzhou City, Fujian Province, China, is an 800-year-old irrigation heritage system comprising the Yanfu Weir and the Fifteen Households Weir, originally constructed during the Southern Song Dynasty (1208–1224 CE). Designed to harness mountain streams through a gravity-fed irrigation network, the system exemplifies the traditional "weir–pond–canal–field" model that efficiently integrates water diversion, storage, distribution, flood control, and agricultural production. The two weirs currently irrigate 1,847 hectares of farmland through an interconnected network of canals, ponds, sluices, and water-measuring facilities that continue to function effectively. Ingeniously adapted to the mountainous terrain, the system employs low diversion weirs, grade-separated channels, and natural topography to ensure efficient irrigation during dry periods and safe flood discharge during the rainy season. Equally remarkable is its long-standing community-based water governance, including the traditional weir chief system, water allocation rules, and quantitative water measurement practices, which have ensured equitable water distribution and sustainable management for over eight centuries. The Changtai Longjin Weirs remain a living example of the harmonious integration of engineering, ecology, agriculture, and local governance, contributing significantly to regional food security, rural prosperity, and cultural development. #ChangtaiLongjinWeirs #ChangtaiDistrict #ZhangzhouCity #icid #china #whis