China Braces for Heavy Rain as Beijing Revives Reservoirs

China is confronting twin flood-related challenges this week as southern provinces brace for a period of concentrated heavy rainfall while Beijing announces its first new mountain flood control reservoirs in nearly half a century — a dual development underscoring the country’s heightened preparedness for extreme weather events.

Southern China Enters Heavy Rainfall Period

Starting from the night of June 12 through June 18, southern China will enter a concentrated period of heavy rainfall, according to the China News Service, citing the Central Meteorological Observatory. The warning covers a vast swath of the country, including Guangdong, Guangxi, western Fujian, southwestern Zhejiang, eastern and southern Jiangxi, southern Hunan, southeastern Guizhou, northwestern and southern Yunnan, and southeastern Tibet.

Forecasters predict heavy to torrential rain, with some areas expected to receive 100 to 200 millimeters within 24 hours, accompanied by short-duration intense rainfall and thunderstorms. The People’s Daily reported that authorities have warned of heightened risks of mountain torrents, geological disasters, and flooding of small-to-medium rivers across the affected regions.

In northern China, the Northeast and North China regions — including the Beijing-Tianjin-Hebei area — are expected to see frequent thunderstorms over the next three days, with localized heavy rain and potential hail.

Beijing’s Historic Reservoir Revival

Concurrently, Beijing has announced the revival of mountain flood control reservoir planning and construction for the first time in nearly 50 years, as reported by Xinhua News. Five new reservoirs are being planned or built across the Yongding, Juma, Dashi, and Wenyu river basins, marking a significant shift in the capital’s approach to flood management.

According to the Beijing Government website, the five projects include the Zuanziling Reservoir (6.77 million cubic meters capacity, expected completion by end of 2028), the Erdaohe Reservoir in Fangshan District, the Xifengshan Reservoir (29.05 million cubic meters), the Yongding River Guantingshan Gorge Flood Control Project in Mentougou District, and the Juma River Zhangfang Flood Control Project in Fangshan District.

“The five new reservoirs have higher design standards than those from the last century, and have referenced historical maximum flood levels,” Yang Xiaolei, Deputy Chief Engineer at the Beijing Water Resources Planning and Design Institute, told Sina Finance.

A Generational Leap in Engineering

All five reservoirs will use concrete gravity dams rather than traditional earth-rock dams, offering significantly greater safety under extreme conditions. Yang Xiaolei explained that traditional earth-rock dams, once overtopped by floodwaters, are highly prone to collapse, potentially creating a “man-made flood peak” that could expand several times or even tens of times. Concrete gravity dams, even if displacement occurs under extreme conditions, will not completely disintegrate, significantly reducing the risk of dam failure.

The new infrastructure will incorporate intelligent monitoring systems and digital twin technology for lifecycle management, representing a generational leap in dam construction standards.

Broader Flood Control Strategy

The reservoir projects are part of Beijing’s comprehensive “up-storage, mid-dredging, down-drainage, effective flood management” strategy. Currently, Beijing has 80 existing reservoirs with a total capacity of 9.3 billion cubic meters, controlling 68% of the city’s mountain area (6,830 square kilometers). Once all five reservoirs are completed, total capacity will reach 10 billion cubic meters, and mountain area control will increase from 68% to 84%.

The reservoirs are designed to protect not just central Beijing but also the city’s sub-center in Tongzhou, the Xiong’an New Area, and the broader Beijing-Tianjin-Hebei region. The Erdaohe Reservoir alone is projected to reduce potential economic losses by approximately 13 billion yuan ($1.8 billion) and directly benefit over 470,000 people.

Historical Context and Climate Adaptation

The revival of reservoir construction comes in the wake of two devastating flood events that exposed critical gaps in Beijing’s infrastructure. The July 2012 “7·21” flood brought 460 millimeters of rain in 18 hours, causing 79 deaths and approximately $1.6 billion in damages. More recently, the July 2023 “23·7” flood in the Hai River basin caused widespread damage in Beijing’s Fangshan and Mentougou districts, directly prompting the renewed focus on mountain reservoir planning.

What to Watch

As southern China begins its week-long period of heavy rainfall, authorities are urging residents in affected areas to prepare for flash floods, landslides, and urban waterlogging. Meanwhile, the Zuanziling Reservoir is expected to be the first of the five new projects completed by the end of 2028, with the Yongding River Guantingshan Gorge Flood Control Project aiming to begin construction by the end of 2026. The coming days will test whether Beijing’s existing flood control systems can hold before these new defenses come online.