How did Shanghai's longest flood drainage system, designed for a once-in-a-century rainstorm, transition from a theoretical plan to actual operation in practice?

Summary of Key Points

Typhoon “Baihaidun” brought unprecedented heavy rainfall to Shanghai (with 316 millimeters of precipitation in 24 hours at Xujiahui Station, setting a record since 1872), causing the water level of the Suzhou River to surge. For the first time, Shanghai activated a temporary pumping emergency plan that had been in preparation for nearly a year: 15 “super pumps” (with a total drainage capacity of 30,000 cubic meters per hour) were used in conjunction with floodgates to divert water from the Suzhou River into the Huangpu River on two occasions, successfully reducing the water level back to a safe range within 100 minutes. Additionally, Shanghai took multiple measures such as pre-reducing the river network water level, cleaning the drainage pipes, and implementing integrated operations to test the effectiveness of its drainage system reform. In the future, Shanghai will continue to improve the capacity and intelligence of its drainage facilities to better cope with extreme rainfall events.

I. Temporary Pumping: From “Plan” to “Actual Combat”

This temporary flood control measure was not a last-minute effort but had been in preparation for nearly a year:

• How was it prepared? The planning began in 2025 due to the increasing frequency of extreme rainfall events, with the strategy being to use pumps as a backup if floodgates were insufficient. The equipment is portable and stored in warehouses, ready to be assembled on-site when needed.
• Has it been tested? Tests were conducted in September 2025, followed by drills in April 2026 to ensure the equipment’s proper functioning.
• Actual results? On August 10th, the pumps were activated twice during both the day and night, draining 30,000 cubic meters of water per hour (equivalent to the capacity of 12 standard swimming pools). This, combined with the use of floodgates, helped rapidly lower the water level in the Suzhou River. Resident Lin Shuning said, “Seeing the water level drop gave me peace of mind,” and there were no significant waterlogging issues in the Jing’an area.

II. Comprehensive Flood Control Measures: More Than Just Pumping

Temporary pumping is just one part of Shanghai’s comprehensive flood control strategy:

• Preparatory Actions: The river network water level was lowered in advance, creating a storage capacity of 450 million cubic meters (equivalent to 320,000 standard swimming pools) to accommodate the excess rainwater. The drainage pipes were also emptied in advance to prevent overflows.
• Dredging for Smooth Flow: 800 kilometers of the central city’s drainage network were thoroughly cleaned to avoid blockages.
• Full Staff Deployment + Intelligent Tools: 15,000 personnel were on duty, operating more than 300 pumping stations to drain a total of over 100 million cubic meters of water. Robots named “Big Buffalo” and “Little Hippo” were also used to remove accumulated water at a rate of 980 cubic meters per hour, significantly improving efficiency compared to manual efforts.

III. The Effectiveness of the Drainage System Reform

Previously, Shanghai’s drainage facilities (sewage treatment plants, pumping stations, and pipelines) were managed by different departments, leading to coordination issues when problems arose. After the 2025 reform, these facilities were brought under the unified management of the Urban Investment Group (known as “Integrated Plant-Station-Network Management”):

• Performance During the Crisis: Coordination was smoother, as integrated management ensured that commands were executed quickly. A total of 15,000 personnel and 32 pump truck teams were deployed to handle the emergency, resulting in a faster response.
• Data Evidence: As of February 2026, 1,555 monitoring devices had been installed across the three main areas (one device every 5 kilometers), providing real-time updates on the drainage system’s status, effectively giving it “clairvoyance.”

IV. Future Flood Prevention: Shanghai’s Long-Term Plan

With the increasing frequency of extreme rainfall events, Shanghai is taking steps to enhance its flood control capabilities:

• Facility Upgrades: By 2030, the area capable of handling “three-to-five-year” once rainfall events in the central city will increase from 70% to 80%. More than 30 new pumping stations, including those at the Suzhou River estuary, will be built, and flood-prone areas will be upgraded.
• Infrastructure Projects: The Wusong River project (Shanghai section) will be advanced, with 200 kilometers of key waterways being renovated to improve drainage.
• Intelligent Technologies: All newly constructed water management projects will feature digital twins (using digital models for simulation and early issue prediction). The integration rate of operations will increase from 18% to 85%, enhancing efficiency.

Conclusion

This typhoon response not only tested Shanghai’s emergency preparedness but also highlighted the challenges posed by extreme weather. The successful implementation of the temporary pumping plan demonstrates the importance of advance preparation. Future improvements in facilities and intelligent technologies will enable Shanghai to better withstand the tests of extreme weather conditions. After all, urban flood control is not a one-time effort but a long-term systematic endeavor.