Flooding record is broken
Can Tho City, the center of the Mekong Delta, is witnessing consecutive flooding records being broken. The worrying thing is that flooding is no longer happening according to the natural law as before but is getting deeper, thicker and more unpredictable.
Master of Technology Quang Vinh - former Chief of Office of the Department of Climate Change Work in Can Tho City - said that Can Tho is suffering the double impact of climate change and subsidence, causing flooding to become increasingly serious. Before 2010, the flood level here rarely exceeded alert level 3. However, from 2011 to now, the situation of exceeding alert level 3 has occurred more frequently. In particular, from 2018 to now, water level records have been continuously broken.
"If it took 10 - 20 years before there was a record-breaking water level, then in the past 7 years, Can Tho has recorded 4 times. In 2025 alone, the highest water level will reach 2.35m" - Mr. Vinh said.
According to Mr. Vinh, a noteworthy reality is that flooding in Can Tho is no longer dependent much on upstream floods. Recent statistics show that the impact of floods from the Mekong River's source to the flooding in Can Tho is not large. On the contrary, high tides in downstream areas tend to have an opposite impact, causing water levels in upstream areas such as Tan Chau and Chau Doc (An Giang) to rise. This goes against the previous perception that major floods from upstream will push water downstream, causing flooding.
The reason, according to Mr. Vinh, is that the land surface of the whole area is sinking evenly, making it easier for high tides to penetrate deeper into the fields.
Many opinions say that urbanization, filling canals, and concreting the ground are the main causes of flooding. However, according to Mr. Vinh, urbanization cannot be completely blamed. "If the population increases and the city develops, urbanization is inevitable. The problem lies in planning when we focus too much on building houses and works without paying attention to trees, water storage space, rainwater drainage and controlling tides and floodwaters from the outside" - Mr. Vinh analyzed.
New approach to prevent flooding
Mr. Vinh said that flooding in Can Tho currently comes from 3 main sources. The first is rainwater, causing flooding in low-lying areas where the drainage system is poor. With this source, the solution is to clearly plan the drainage basin, build a collection system and pumping station to proactively drain.
Second, water from the outside overflows into urban areas, including high tides and floodwaters from the Mekong River. This is a very large water source, temporarily stored like rainwater. The main solution is the system of dykes, embankments and regulating sewers, allowing control of water entering and exiting at times.
Third is subsidence. If subidence cannot be controlled, all construction solutions are temporary.
To effectively prevent flooding, according to Mr. Vinh, it is important to change the approach. "The flooding is due to the extreme water level, not the average water level. If we only take average data, we cannot fight flooding" - he emphasized.
In addition, projects need to use the latest, live measurement data, instead of relying on past data that is no longer suitable in the context of rapid climate change.
"In particular, controlling land subsidence must be given top priority. If this problem cannot be solved, all flood prevention works, even with large investments, will soon be "delayed" compared to reality" - Mr. Vinh noted.
