What is the location of the flooding?
As of September 24, 2025, the Super Typhoon Ragasa has unleashed catastrophic flooding across Taiwan, Hong Kong, and China’s southern Guangdong province.
In Taiwan’s Hualien city, a barrier lake burst its banks, inundating Guangfu township. Hong Kong faced storm surges up to five meters, while southern China’s coastal areas, including Shenzhen and Zhuhai, were battered as Ragasa made landfall with sustained winds over 190 km/h.
The storm has displaced over a million people and continues to affect vast stretches of East Asia (1).
Which cities or areas are affected by the flooding?
Taiwan’s Hualien city has suffered the worst impact, with Guangfu township devastated by sudden flooding. Hong Kong saw widespread disruption in districts like Heng Fa Chuen and Lei Yue Mun, where massive waves and flooding hit coastal neighborhoods.
In southern China, the affected areas include:
Across Guangdong province, more than a million residents have been relocated as Ragasa sweeps through the region. Emergency shutdowns and mass evacuations have been implemented (2).
What is the current containment status of the flooding?
Containment remains extremely challenging. Taiwan has mobilized government ministries and military units for rescue and disaster cleanup, but 124 people remain missing in Hualien.
In Hong Kong, the Observatory issued its highest warning signal (T10), warning of destructive winds and flooding. Southern China has evacuated over a million residents, with schools, factories, and transit shut down in multiple cities.
Relief operations are ongoing, though heavy rains and storm surges continue to hamper rescue efforts (3).
Are there any evacuation orders or alerts in place?
Mass evacuations have been ordered across multiple regions. In Taiwan, thousands sought refuge on rooftops before being rescued as floodwaters receded.
Hong Kong authorities suspended schools, flights, and businesses, urging residents to stay indoors. In Guangdong province, over one million people were relocated, with Shenzhen alone evacuating half a million people.
Authorities continue to warn residents not to go out except for emergencies, as strong winds, storm surges, and flooding pose ongoing threats across East Asia (4).
How can I protect myself from mold after flooding?
It’s important to take steps to prevent mold after a flood.
- Before entering a flooded area, make sure it is safe and free from electrical hazards or structural damage.
- Use protective gear: wear gloves, goggles, and a KN95/FFP2 mask to minimize exposure to mold spores.
- If there is still standing water, remove it as quickly as possible. Use pumps, wet-dry vacuums, or buckets to extract the water.
- Open windows and doors to facilitate air circulation and use fans, dehumidifiers, and HVAC systems to help dry the space. This step is crucial within the first 24-48 hours after flooding to prevent mold growth.
- Remove and discard any items that have been severely damaged by floodwater and cannot be thoroughly cleaned and dried. This includes carpets, upholstered furniture, mattresses, and any other porous materials.
- Thoroughly clean all hard surfaces with a detergent or cleaner suitable for mold remediation. Use a solution of 1.5 cups of bleach mixed with one gallon of water to disinfect nonporous surfaces. Never mix bleach with ammonia or other cleaning products, as the fumes are toxic.
- Maintain an indoor relative humidity (RH) of 35-50%. High humidity promotes mold growth, so consider using dehumidifiers in damp areas.
- Run a high-performance air purifier for mold, both during and after the mold removal work.
- If the flooding and mold damage are extensive, consider contacting professionals specializing in mold remediation to ensure proper cleanup and restoration.
Remember, mold can pose health risks, so it's important to take these steps promptly and thoroughly. If you experience persistent mold-related health issues or have concerns about extensive mold growth, consult with a medical professional or a mold remediation specialist.
