Great pressure from the 2025 rainy season
According to Hanoi Drainage One Member Limited Liability Company, 2025 is recorded as one of the years with complex weather diễn biến in the Capital in recent years.
As of November 27, 2025 (according to the results of implementing the drainage assurance plan for the 2025 rainy season), the average rainfall in the inner city of Hanoi reached about 2,050mm, with 77 days of rain. In the remaining areas, the average rainfall reached about 1,801mm, with 76 days of rain.
The inner city area had 65 days of rain with rainfall over 50mm; this number in the remaining areas is 42 days. Many heavy rains appeared in a short time, creating great pressure on the urban drainage system.
Hanoi is also directly affected by many storms such as storm No. 3 Wipha, storm No. 5 Kajiki, storm No. 9 Ragasa, storm No. 10 Bualoi and storm No. 11 Matmo. The total rainfall in the storm's impact periods ranges from nearly 200mm to more than 900mm, with days of rainfall up to about 420mm.
Several independent extreme rains also appeared, typically on June 30 and August 25, with rainfall in many central areas exceeding 150-300mm.
Remember at the end of September, early October 2025, the circulation of storms No. 10 and No. 11 caused heavy rain in Hanoi. At this time, the city recorded more than 200 flooding points; some areas were flooded 50-70cm deep, lasting 3-5 days, affecting traffic and people's lives.
Faced with this reality, the city identifies flooding as one of the 5 "bottleneck points" that need to focus resources on overcoming.
Accelerate investment in flood prevention works
To solve the above situation, Hanoi is implementing urgent construction projects, local flood control projects and public investment projects according to planning.
Including 10 emergency construction investment projects, including 5 drainage system projects and 5 regulating lake projects.
Along Thang Long Avenue, existing pumping stations have been renovated and increased capacity; and at the same time, field pumping stations have been added, and drainage culverts and ditches have been built.
At Resco, Ecohome, Tay Ho Tay, Diplomatic Corps, Ciputra, Vo Chi Cong, Long Bien, Dong Anh, Gia Lam... many drainage items have also been supplemented and renovated.
According to the Plan to ensure drainage and prevent flooding in the inner city area in the 2026 rainy season, with rainfall of 70-100mm/hour, Hanoi is forecast to have 71 localized flooding points. This is a scenario built for the city to proactively arrange forces, vehicles and handling plans.
Many flooded spots are being improved
The reality of rains in the 2026 rainy season shows that some areas that were once frequently flooded have changed.
Areas that were flooded for a long time in 2025 such as Thang Long Avenue, Diplomatic Corps, Tay Ho Tay, Ecohome, Duong Dinh Nghe - Pham Hung, Nguyen Trai... have not yet experienced flooding or the water receded quickly after heavy rain.
Some areas recorded rainfall exceeding 100mm, but deep and prolonged flooding is no longer as common as before.
However, the system still has some localized flooding points when heavy rain concentrates in a short time. According to a report by Hanoi Drainage One Member Limited Liability Company at 6:00 AM on September 16, 2026, flooding locations recorded include Co Linh street, Ngoc Lam street, Phu Xa street, Hoa Bang street, Trieu Khuc street and the end of alley 42 Giang Van Minh.
Also according to Hanoi Drainage One Member Limited Liability Company, local flood control works continue to be identified as an important solution to directly handle the remaining points on the system, especially areas with high construction density, old infrastructure and limited drainage space.
After completion and commissioning, these projects help improve collection capacity, shorten drainage time and reduce flooding levels in key locations.
In the context of increasingly unpredictable weather, Hanoi Drainage One Member Limited Liability Company assesses that the work of preventing and combating storms and flooding in 2026 needs to be proactive at a high level.
Along with investment projects, the operation of the system, maintenance of on-duty forces and timely handling of arising points will continue to be an important factor in reducing the impact of heavy rain in Hanoi.
