Hong Kong Flood Disaster Prevention: How Two Storms Changed Future Strategies

Hong Kong’s Disaster Response Innovation Seen Through the Lessons of the 2023 Mega Flood and the 2025 Robotic Efforts

• Understand the limitations of Hong Kong’s flood defense system revealed by the record-breaking rainfall in 2023, the worst in 140 years.
• See how the latest pumping robots and smart technologies are transforming disaster response paradigms.
• Explore the blueprint of future cities moving toward ‘sponge city’ concepts to combat climate change.

As climate change accelerates, cities worldwide face unprecedented natural disasters. Hong Kong’s case offers many insights. This article deeply analyzes how Hong Kong’s flood disaster prevention system evolved through two extreme rain events and the pivotal role of technology at its core.

The 2023 Mega Flood: Confronting the Limits of Existing Defense Systems

In September 2023, Hong Kong experienced the worst rainfall in 140 years of meteorological records. The low-pressure trough left by Typhoon Haikui dumped an astonishing 158.1mm per hour. This far exceeded the design capacity of Hong Kong’s sophisticated triple defense system (barriers, retention, and improvement), which was built for up to a 200-year event.

Floodwaters inundated many parts of the city, with Wong Tai Sin MTR station completely submerged under waterfall-like torrents. The event resulted in 4 deaths, 144 injuries, and economic losses estimated at about 1.5 billion HKD, exposing the clear limitations of the static, infrastructure-centered defense strategy. The government’s delayed response and the phrase “once in 500 years rainfall” drew public criticism.

2025 and the Arrival of Robots: The Dawn of a New Response

Two years later, in August 2025, Hong Kong faced another record-breaking rainfall (setting a new daily precipitation record for August). But this time, the response was different. Learning from the painful experience of 2023, the Drainage Services Department (DSD) urgently deployed new pumping robots on site.

These robots were stationed in frequently flooded areas such as the Wong Chuk Wai Estate parking lot, which suffered heavy damage in 2023, and demonstrated remarkable efficiency by removing water from the flooded parking lot in just one hour. This marked a symbolic shift in Hong Kong’s disaster response paradigm from static defense to dynamic, technology-driven rapid response.

Technological Evolution in Hong Kong Flood Prevention: Smart Drainage Systems

Pumping robots are not standalone devices. They are key components of a larger ‘smart drainage’ initiative integrated with over 300 sensors citywide, IoT, and AI-based prediction systems. What impressed me most during this analysis was how robot technology, originally used for routine drainage maintenance, was immediately deployed in emergencies to maximize its utility.

DSD Key Robot Technologies

Comparison: Static Defense vs Dynamic Response

The two flood cases highlight stark differences in Hong Kong’s flood prevention strategy.

Checklist: Flood Disaster Prevention Strategies for Future Cities

Hong Kong’s experience offers important lessons for other cities. In the era of climate change, how should our cities prepare?

1. [✔️] Establish smart monitoring systems: Install water level and rainfall sensors citywide to collect real-time data and use AI to predict floods.
2. [✔️] Form robot-based rapid response teams: Deploy pumping and dredging robots to quickly address issues in risky areas without putting people in harm’s way.
3. [✔️] Adopt the ‘sponge city’ concept: Expand permeable pavements, rooftop greening, and rain gardens to enhance the city’s ability to absorb and retain rainwater.

Climate change is increasing the frequency and intensity of extreme rainfall events worldwide.

Conclusion

Hong Kong’s story of two storms vividly illustrates learning from disasters and overcoming crises through technology. The survival and prosperity of future cities can no longer rely solely on massive concrete structures.

• Key Summary:

  1. The 2023 mega flood clearly exposed the limits of static, infrastructure-centered defense systems.
  2. The 2025 robot deployment demonstrated the effectiveness of dynamic, technology-driven responses combined with AI and IoT.
  3. Future Hong Kong flood prevention is moving toward a multilayered approach combining robust infrastructure, advanced technology, and the nature-coexisting ‘sponge city’ concept.

I hope this article encourages you to take a closer look at your city’s disaster response systems.