Beijing Revives Mountain Flood Control Reservoir Plans

Beijing has revived plans to build mountain flood control reservoirs for the first time in nearly half a century, announcing on June 11 the construction of five new reservoirs across four river systems. The move, confirmed by the Beijing Water Authority, represents a generational infrastructure investment aimed at protecting the capital and surrounding regions from the kind of catastrophic flooding that devastated the area in July 2025.

A Direct Response to Disaster

The announcement comes less than a year after the July 2025 Beijing-Tianjin-Hebei floods, one of the most destructive natural disasters to hit northern China in decades. Extreme rainfall — with some areas recording over 700 mm — killed at least 60 people, displaced more than 100,000, and caused economic losses exceeding 100 billion yuan, according to reports from Xinhua News Agency.

The 2025 disaster exposed critical vulnerabilities in Beijing’s water management infrastructure. The Miyun Reservoir, the capital’s primary drinking water source, recorded its largest inflow since construction in 1959 — 6,550 cubic meters per second — forcing emergency discharges that overwhelmed downstream areas, as reported by the Global Times. Seventeen major dams across Miyun, Huairou, and Pinggu districts conducted coordinated emergency discharges, with the simultaneous closure of 352 mountain flood channels compounding the crisis, according to Probe International.

The Five New Reservoirs

The five projects — Erdaohe, Zuanziling, Xifengshan, Yongdinghe Guantingshan Gorge Flood Control Project, and Jumahe Zhangfang Flood Control Project — are being developed across the Yongding, Juma, Dashi, and Wenyu river systems, as detailed by 21 Economic News.

Beijing currently has 80 completed reservoirs covering 6,830 square kilometers — 68% of the city’s mountainous area. Once the five new reservoirs are operational, that coverage will rise to 84%, forming an integrated flood control barrier across Beijing’s northern and western mountainous regions.

Erdaohe Reservoir, the largest of the new projects, is already in full construction in Fangshan District’s Fozizhuang Township. With a total storage capacity of approximately 76.32 million cubic meters and a maximum dam height of 100 meters — making it the tallest dam in Beijing — it will control a basin area of 493 square kilometers. A supporting road relocation project with a total investment of 6.23 billion yuan has already completed bidding, as reported by Seetao.

Zuanziling Reservoir in Changping District’s Xingshou Town and Xifengshan Reservoir in Changping’s Liucun Town are also under construction, with storage capacities of 6.77 million and 29.05 million cubic meters respectively.

The Yongdinghe Guantingshan Gorge Flood Control Project in Mentougou District, controlling a 1,397-square-kilometer basin, is expected to begin construction by the end of 2026. The Jumahe Zhangfang Flood Control Project in Fangshan District, the largest in terms of controlled area at 4,460 square kilometers, remains in the project approval stage.

Expert Perspectives

“Reservoirs can effectively reduce downstream flood pressure through methods such as ‘blocking, storing, reducing, and staggering,’” Yang Xiaolei, Deputy Chief Engineer of the Beijing Water Resources Planning and Design Institute, told Xinhua.

Fan Bin, Director of the Water Conservancy Project Construction Division at the Beijing Water Authority, explained that after completion, the five reservoirs will “form a flood control barrier composed of reservoir clusters in Beijing’s northern and western mountainous areas,” improving flood control standards for the central urban districts, the Beijing Municipal Administrative Center in Tongzhou, and Xiong’an New Area.

However, water specialist Wang Jian, a former Beijing water official, has cautioned that Beijing’s reservoir management strategy creates inherent tensions. As he told Probe International, keeping reservoirs like Miyun at near-capacity year-round to ensure drinking water supply means that during extreme rainfall, “this strategy backfires: excessive inflows force emergency discharges, overwhelming downstream areas.”

Broader Implications

The reservoir initiative fits into China’s broader strategy of massive infrastructure investment for climate adaptation. The projects follow the “upper storage, middle dredging, lower drainage” principle and are explicitly designed to strengthen the Beijing-Tianjin-Hebei regional flood control system, reflecting the coordinated development strategy for the region.

As Reuters noted in its analysis of Beijing’s climate adaptation challenges, historically arid Beijing faces a wetter future as climate change increases the frequency and intensity of extreme weather events. The 2025 floods followed similar devastating events in 2023 and the deadly “7·21” rainstorm of 2012 that killed 79 people.

Challenges Ahead

While the announcement marks a significant policy shift, several challenges remain. The Jumahe Zhangfang project has not yet received final approval, and the Erdaohe Reservoir is not expected to be completed until 2030, meaning full flood protection remains years away. The total cost across all five projects is expected to be substantial, with just the Erdaohe road relocation costing over 6 billion yuan.

Environmental concerns also loom large. Large dam construction in mountainous areas may have ecological consequences, including habitat fragmentation and altered river ecosystems. The projects will also require significant population displacement, though specific resettlement figures have not yet been disclosed.

What to Watch For

As construction progresses, key questions remain unanswered: What is the total estimated cost for all five projects? How many people will be relocated? And most critically, how will these new reservoirs be operated to balance the competing demands of flood control and water supply — the very tension that the 2025 floods so devastatingly exposed?

For now, Beijing has taken its most significant step in decades toward building a more resilient water infrastructure. Whether the new reservoirs can keep pace with a rapidly changing climate remains the open question.