Mekong Eye (mekongeye.com) là trang web và mạng lưới báo chí chuyên cung cấp thông tin về môi trường, khí hậu và các vấn đề phát triển tại khu vực sông Mê Kông.

Đây là một dự án truyền thông phi lợi nhuận của Mạng lưới Báo chí Trái đất (Earth Journalism Network – EJN) thuộc tổ chức quốc tế Internews. Dự án này cũng nhận được sự tài trợ từ Cơ quan Hợp tác Phát triển Quốc tế Thụy Điển (Sida).

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A Mekong Delta city’s fight against flooding (part 1)

mekongeye – By Lê Đình Tuyển

27 October 2025 at 11:42 (Updated on 3 November 2025 at 20:12)

Infrastructure that cost hundreds of millions of US dollars still leaves many parts of Cần Thơ under water

A resident of Bùi Hữu Nghĩa street, which lies outside Project 3’s protection zone, wades in knee-deep water during record-high spring tide in October 2025. PHOTO: Lê Đình Tuyển.

CẦN THƠ, VIET NAM – Every flooding season, spring tides inundated the Cần Thơ Cardiovascular Hospital, with water reaching up to the patients’ beds. Caretakers used to stay up all night to bail the water out, bucket by bucket.

However, in October, a spring tide on the Hậu (Bassac) river, which runs from the Mekong and Tonle Sap rivers in Cambodia to the Mekong Delta in Viet Nam, rose to the highest levels ever recorded, yet the hospital stayed dry.

So did some of Cần Thơ’s main roads, which used to be flooding hotspots.

Cần Thơ, a major city in Viet Nam’s Mekong Delta, has been battling against severe flooding caused by heavy rain and spring tides. In the past decade, it raised roads, built embankments and tidal sluice gates to cope, using a 9.2 trillion VND (US$350 million), more than 60% of which are loans from the World Bank.

The costly measures, known as Project 3, were supposed to protect 2,700 hectares of the city’s core area when complete.

Now in the final stage, it protects some areas, floods some and turns many zones outside the protected areas into vast pools of water.

At Ninh Kiều wharf, the city’s tourism hotspot, a kilometer of embankment was left incomplete as authorities waited for future funding. This gap allowed water into some of the city’s core areas.

Nguyễn Văn Tho, the project’s deputy director, explained that the wharf’s embankment needed a more solid solution, rather than a simple railing as previously proposed, hence the delay.

Such project gaps now call for more costly investment, yet as the flooding continues, their sustainability remains in question.

Sunken homes

Sitting inside his damp, low-lying house in alley 2 on Lý Tự Trọng Street, 76-year-old Nguyễn Văn Son stared helplessly at what now feels like a dike blocking his front door.

“The alley used to be 25 centimeters lower than my floor, but after the upgrade, it’s now more than one meter higher,” he said.

Son’s family now climb up and down an iron staircase every day just to enter their home.

One year ago, Son and other families in the neighborhood each contributed 2.7 million VND ($76) to elevate Alley 2, in addition to local government funding. After the upgrade, they had to put in nearly 100 million VND ($3,800) more to fix the front of their house.

“It’s where we keep our drinks stall and parked our motorbikes, so we had to fix it,” said Son’s daughter Hiền, who sells herbal coconut drinks for a living.

“The floor was so low we couldn’t even push the bikes in or out,” she added.

To raise the entire house up to the alley level, Son’s family now face a cost of at least 200 million VND ($7,600) – an amount they cannot afford.

Only a few houses down, Phạm Thanh Hoàng’s home has also been severely impacted. The house is cluttered, and their motorbikes are now parked permanently on the street.

To keep out dust and rainwater, Hoàng has to put up a plastic barrier across the doorway.

“We’re no longer worried about tidal flooding, but during heavy rain, if we don’t cover the front, all the water pours straight into the house,” he explained.

Sunken houses are easy to spot along several main roads of Cần Thơ, as the city continues to raise its roads to combat floods.

The elevations have turned Cái Khế, a key commercial center, into a low-lying zone.

Weak drainage

While Project 3’s ability to hold back river water remains in question, heavy rain keeps exposing the city’s weak drainage system.

After every downpour, many roads in the city center become submerged. Several of the worst-hit roads, including Ngô Quyền, Lê Thánh Tôn and Nguyễn Trãi, are part of a nearly 282-billion-VND ($10.7 million) package under Project 3 launched in 2024.

Project 3 deputy director Nguyễn Văn Tho blames the flooding on public misdemeanors.

“The storm drains are clogged with trash and leaves. Some households even cover them with rubber sheets to block odors, and when it rains, they forget to remove them. The water has nowhere to go,” he said.

When surface drains fail, streets overflow, and the system below can’t collect enough water to activate two newly built pumping stations.

Yet that explanation only scratches the surface.

Nguyễn Hữu Thiện, an independent specialist on the Mekong’s ecology, believes that flooding caused by rainfall in Cần Thơ is a direct consequence of short-sighted urban planning.

“The city has been overly concretized at the cost of nearly all its natural water-absorbing spaces such as green areas and soil surfaces,” he said.

“This concretization has also caused Cần Thơ to lose its natural inner-city canal system, a gift from nature,” Thiện added.

With no soil left to absorb and no canals for drainage, all that water has nowhere to go but the concrete streets, he said.

A recent inspection by the Cần Thơ Department of Construction of 11 major downtown streets and two pumping stations also revealed the system’s flaws in the size of the drainage pipes.

According to the inspection results, many of the city’s drainage pipes were designated outdated and too small, with diameters ranging from only 0.4 to 1 meter wide – far too small to handle the city’s floods.

Take Cách Mạng Tháng Tám Street, one of the most flood-prone streets during both rain and high tides, for example. It has only D600 and D400 drainage pipes, which run along one side of the road and are sometimes disconnected.

On Nguyễn Văn Cừ Street, the main drainage line has sagged due to land subsidence, forming water pockets that constantly trap stagnant water.

Across most surveyed streets, storm inlets have been narrowed, degraded or clogged with mud and garbage. Manholes, too, are filled with sludge and wastewater, even in dry weather.

More critically, many outfalls and canals have been encroached upon or severely narrowed.

At Sao Canal along Nguyen Van Cu Street, the flow has shrunk to just 40-60 centimeters wide. The outfall at Bà Nga Canal on 30/4 Street now sits inside a private home, while drainage canals along Võ Văn Kiệt Street and the Metro residential area have been almost entirely built over.

In addition, elevation mismatches between drainage pipes and outfalls on several roads prevent the water from flowing out.

A water management specialist, who asked not to be named, said: “The biggest problem is the lack of coordination.”

“Drains, small and large, are designed at different elevations with no coordinated system, while carrying both wastewater and stormwater. Household wastewater should be piped to treatment plants, while rainwater should have a separate collection and drainage network,” the specialist explained.

“Honestly, with the current situation, it could take another 20 years before these issues are properly resolved,” he added.

Mismanagement

Despite the systemic issues, the Cần Thơ Department of Construction’s solutions remain largely stopgap and reactive. The department wants to dredge and repair all outfalls, catch basins, manholes and sewer lines, as well as repairing one-way valves.

As for canal and drainage encroachment, it only urges local wards to actively persuade residents to dismantle illegal structures, while asking the Department of Natural Resources and Environment to take the lead in reviewing and proposing ways to restore the city’s natural waterways.

An urban infrastructure official, who also wished to remain anonymous, admitted that the implementation of the city’s master plan for ground elevation and surface drainage was a web of contradictions.

The plan aimed to protect the city’s core area with a system of floodwalls and embankments reaching +2.75 meters, sluice gates, tidal barriers and high-capacity pumping stations. The core area could remain at its low elevation once this infrastructure was completed.

But in reality, the inner core has seen a frenzy of fragmented upgrades. Across central districts, roads and alleys have been piecemeal elevated to heights of +2.3 meters or more, often in clear disregard of the official plan.

By the time major flood-control projects are finished and begin to function as intended, the over-elevated inner roads such as Alley 2 or those surrounding Cai Khe commercial center, will have rendered those protections meaningless.

In the meantime, the frenzy leaves families like Son’s trapped in an exhausting, costly cycle.

The city has seen poor implementation before. Prior to Project 3, Project 2, which was worth more than 1.85 trillion VND ($70 million), left a retention pond launched in 2016 covered with overgrown weeds and trash.

A February 2024 inspection by the Cần Thơ Inspectorate uncovered multiple violations in the implementation of Bún Xáng Lake, the retention pond.

Meanwhile, a far greater threat looms over Cần Thơ and the entire Mekong Delta: land subsidence. Among the hardest-hit areas in the Delta, Cần Thơ stands near the top of the list.

Read part 2 of the story here.

This story also appeared in the Thanh Niên Newspaper in Vietnamese in October 2025. This version was translated to English using AI and edited by Mekong Eye.

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A Mekong Delta city’s fight against flooding (part 2)

mekongeye – By Lê Đình Tuyển

3 November 2025 at 20:04 (Updated on 6 November 2025 at 4:07)

As the ground in the delta sinks at alarming rates, infrastructure solutions remain mere stopgaps

A Cần Thơ resident sits at a public bench at Ninh Kiều Wharf, the city’s tourism hotspot, during the record high tidal flood in October 2025. PHOTO: Lê Đình Tuyển.

CẦN THƠ, VIET NAM – For the past four years, Kỷ Quang Vinh’s house had sat comfortably above the elevated road.

Unlike less well-off residents, the former deputy head of Cần Thơ’s Office of Climate Change Affairs had US$4,000 to renovate his house when the city started lifting its roads.

When Vinh bought the property in 2000 in Khai Luông, a tributary of the Hậu (Bassac) river, he did not think his house would one day be flooded during a spring tide.

He was proven wrong in 2017. The highest spring tide reached 2.13 meters that year, lower than the 2011 record level of 2.15m, yet his house was inundated for the first time.

“The same floor is flooded by a lower water level – it has to be due to land subsidence,” Vinh contended.

According to a report by the Department of Surveying and Mapping, at a benchmark across the river and opposite Vinh’s house, the ground had sunk by 51.6cm between 2005 and 2017.

A study from Utrecht University published in 2017 revealed that the Mekong Delta had sunk on average by 18cm between 2002 and 2017, with areas over 30cm. It warned that the delta would continue to subside at an alarming rate of 1.1cm per year and as high as 7cm per year in Ho Chi Minh City.

The 2020 Climate Change Scenario report by the Ministry of Agriculture and Environment showed similar trends. It further warned that subsidence funnels have started to form in some urban areas such as Cần Thơ and Cà Mau.  

Flooding in the delta will become even more severe when compounded by sea-level rise, which is increasing by about 3mm per year, the report said.

It predicted that with an 80cm rise in sea levels, about 32% of the Mekong Delta’s area would be at risk of inundation. With a 100cm rise, nearly half the delta would be at risk.

In the former Cà Mau and Kiên Giang (now An Giang) provinces, these figures would be 80% and 76% respectively.

A deflated watermelon

Vinh clearly remembers each time a new tidal record was set on the Hậu (Bassac) river.

First it was 2.15m in 2011, then 2.23m in 2018, 2.25m in 2019 and 2.27m in 2022 – all while flood volumes from the upstream Mekong steadily declined. 

Downstream factors are now at play, he concluded.

According to the government’s 2020 climate change report, the extraction of groundwater is the main driver behind land subsidence, in addition to natural sediment compaction.

In the past three decades, as the delta pursued industrial farming, excessive use of synthetic fertilizers and chemicals has polluted its surface water. Lacking alternatives, industrial complexes, farms and residents have dug millions of wells, draining the ancient groundwater layers, which cannot naturally replenish itself.

“It is such a paradox that water in the Mekong Delta is abundant, yet it is unusable,” said Nguyễn Hữu Thiện, an independent specialist on the Mekong’s ecology.

“Just 30 years ago, people could still drink river water, but now the entire delta relies on groundwater. This is the consequence of an agricultural system obsessed with productivity – over-using fertilizers and chemicals and aggressively interfering with nature,” Thiện added.

“Just 30 years ago, people could still drink river water, but now the entire delta relies on groundwater. This is the consequence of an agriculture system obsessed with productivity – overusing fertilizers and chemicals and aggressively interfering with nature.”

Nguyễn Hữu Thiện, ecologist

He drew an analogy: “Extracting groundwater is like living on a giant watermelon. The more you stick straws in to suck out the water, the faster the watermelon deflates.”

According to the government’s 2020 climate change report, if groundwater extraction in the Mekong Delta does not slow down, the region’s ground could sink by an additional 35cm to 140cm by 2050.

As the delta sinks, Vinh admitted that the road elevation was Cần Thơ’s last resort.

Yet it is unclear how long the new infrastructure can hold. This October, Vinh was as equally surprised as the other city residents when tidal records were broken twice – 2.33m, higher than most elevated roads in the city center, which are at 2.3m.

Controlling water

Project 3, which builds embankments and sluice gates to protect Cần Thơ’s urban core, is the final link in a decades-long chain of efforts to control the delta’s water, said ecologist Nguyễn Hữu Thiện.

Severe urban flooding was merely the direct consequence of depriving water of its natural space to flow, he argued.

Prior to the 1990s, floodwater from the upstream Mekong used to be retained in two giant natural catchments – the Plains of Reeds and Long Xuyên Quadrangle – at estimated capacity of 10 and 9.2 billion m³ respectively.

After the country shifted from state subsidies to a market economy in 1986, an extensive network of enclosed dike systems were built across these two retention areas to allow farmers to grow three rice crops a year.

Productivity skyrocketed, while the delta lost the ability to retain a total of 8.2 billion m³ of water, Thiện said.

“When water can no longer flood the fields, it inundated the downstream orchards in the Hậu (Bassac) and the Tiền basins,” explained Thiện.

Fruit farmers then started to build enclosed dikes to protect their orchards. Soon, the entire downstream of the delta was also covered with dikes.

Along the coastline, the government was building sea dikes and sluice gates to alleviate saltwater intrusion. This infrastructure further left tidal waters with little room to disperse, forcing them to flood the main rivers.

When upstream floodwaters and tidal flows converge in central delta areas such as Cần Thơ and Vĩnh Long, and can no longer spread into rice fields or orchards, the only space left for it to go is the city streets.

Project 3 will further redirect this flow, Thiện said. While it can block the convergent flow within the urban core of Cần Thơ, suburban zones such as Bình Thủy, Cái Răng and Ô Môn will instead be flooded.

Relinquish control

To address flooding in urban areas such as Cần Thơ and across the Mekong Delta, a mindset shift is needed, argued Thiện. As the government’s Resolution 120 on sustainable development of the Mekong Delta in response to climate change issued in 2017 stated, humans need to stop fighting against nature and start adapting to the delta’s natural rhythms.

The solution can start with ending the over-extraction of the land, reducing and eventually banning groundwater extraction, especially in urban areas, while restoring surface water quality by changing agricultural practices, said Thiện.

“The agriculture sector holds the key to solving land subsidence in the delta,” he said. “Agriculture must shift toward less intensive practices such as reducing chemical use, avoid chasing sheer output, and stop aggressively interfering with nature.

“We could start by cutting back on triple-crop rice cultivation in upstream areas such as the Long Xuyên Quadrangle and the Plain of Reeds, to restore the natural flood-retention spaces.”

Thiện emphasized that these solutions were clearly supported in Resolution 120 and the 2022 Integrated Mekong Delta Plan under the umbrella term thuận thiên, meaning nature-based.

These documents called for the treatment of saline, brackish and floodwaters not as enemies to be blocked at all costs, but as vital resources and opportunities for reorganizing production.

Rather than trying to desalinize coastal areas or build upstream dikes to boost rice yields, the focus should be on creating space for water and developing economic models suited to alternating saline-brackish-freshwater zones.

Tô Văn Trường, a veteran water resources specialist, listed five governance issues to be addressed in order to implement such nature-based solutions.

First, there needs to be a single authoritative agency with power to coordinate all flood management efforts across administrative boundaries, ending the fragmented, counter-productive approach.

Next, water planning must be smart, based on unified ground levels and combined with digital flood-risk mapping. Retention ponds should be treated as inviolable ecological areas, while encroachments and the filling of canals, rivers and ponds should even face criminal charges.

Thirdly, nature-based solutions should be prioritized. There needs to be a shift from concrete sluice gates and pumps to green infrastructure such as wetland restoration, ecological parks, rain gardens and permeable materials. Such measures can reduce floods, lower urban heat and boost biodiversity.

At the same time, funding must be diversified through innovative mechanisms to attract private investment, issue green bonds and access international climate finance.

Last but not least, technology and community engagement are essential. There is a need for smart early-warning systems, while citizens should be engaged in monitoring and feedback roles.

For Kỷ Quang Vinh and Cần Thơ residents, the 2.33m mark was not only a historic record or an unusual hydrological event. It was also a stark warning, revealing that raising ground levels are merely costly stopgaps, a part of an endless, self-perpetuating cycle.

Read the first part of the story here.

Correction: A previous version of this story published on Monday, November 3, 2025 reported that “Prior to the 1990s, floodwater from the upstream Mekong used to be retained in two giant natural catchments – the Plains of Reeds and Long Xuyên Quadrangle – at a capacity of 3.5 and 4.7 billion m³ respectively.” We have edited this sentence to reflect the accurate figures. We sincerely apologize for this editorial mistake.

This story also appeared in the Thanh Niên Newspaper in Vietnamese in November 2025. This version was translated to English and edited by Mekong Eye.

Unless stated otherwise, the names of localities, cities and provinces in this article reflect Viet Nam’s administrative reform, which took effect on July 1, 2025.

About the writer

Lê Đình Tuyển

Lê Đình Tuyển is a full-time journalist at Thanh Nien, a Vietnamese newspaper based in Ho Chi Minh City. His news report focuses on the current affairs in the Mekong Delta. More by Lê Đình Tuyển