Vietnam Rethinks Flood Management in Face of Escalating Climate Threats

Vietnam is fundamentally reimagining its approach to flood management after enduring a year of devastating storms that collapsed hillsides and submerged vast portions of urban areas across the country.

From mapping high-risk zones to transforming cities into water-absorbing “sponges,” Vietnam is investing billions to adapt to what experts describe as a new era of climate extremes. Under a comprehensive national master plan that runs through 2030, the government has committed more than $6 billion to construct early-warning systems and relocate vulnerable communities away from danger zones.

In mid-sized cities like Vinh in central Vietnam, these concepts are already taking shape. Authorities are expanding drainage networks, carving out designated flood basins, and converting riverbanks into green spaces capable of absorbing rainfall before gradually releasing it.

The urgency of this work has been underscored by an unprecedented series of storms this year. Typhoons Ragasa, Bualoi, and Matmo each carved their own path of destruction across the country, with record rainfall transforming streets into rivers and triggering landslides, leaving communities with barely any time to recover between disasters.

As Typhoon Kalmaegi gathered strength on its trajectory toward Vietnam this week, scientists warned it likely won’t be the last severe storm of the season. According to Benjamin Horton, professor of earth science at City University of Hong Kong, “Vietnam and its neighbors are on the front lines of climate disruption.”

Climate scientists emphasize that this succession of storms battering Vietnam isn’t an anomaly but represents a broader shift in storm behavior on our warming planet. Although Vietnam typically faces around a dozen tropical storms annually, the 2025 cluster represents a “clear signal” of global warming, Horton noted.

Ocean waters have warmed nearly 1 degree Celsius since the pre-industrial era, allowing storms to carry significantly more moisture and deliver more intense rainfall.

Economic Toll Mounts

The economic impact has been severe for Vietnam, a developing nation with ambitious goals to achieve high-income status by 2045. Floods routinely disrupt farming, fisheries, and manufacturing—the backbone of its economy. State media estimate extreme weather has already cost the country $1.4 billion in 2025 alone.

Looking forward, Vietnam projects it will need to spend between $55 billion and $92 billion this decade just to manage and adapt to climate change impacts.

Urban Vulnerability Exposed

Approximately 18 million people—nearly one-fifth of Vietnam’s population—live in its two largest cities, Hanoi and Ho Chi Minh City. Both are situated on river deltas that historically functioned as natural buffers against flooding. However, as urbanization spread concrete over wetlands and farmlands, these cities lost their natural capacity to absorb heavy rainfall.

Flooding in Hanoi this October persisted for nearly a week in some neighborhoods. The capital city of over 8 million has outgrown its infrastructure, and its colonial-era drainage system failed catastrophically as streets transformed into brown canals. Motorcyclists struggled through waist-deep water while the Red River’s levees were pushed to their limits.

Vegetable seller Dang Thuan’s home flooded knee-deep, ruining her inventory. Her neighborhood once contained several ponds, but they were filled in to construct houses and roads, leaving nowhere for water to drain.

“We can’t afford to move,” she explained. “So every time it rains hard, we just wait and hope.”

Studies reveal the rapid loss of water-absorbing spaces in Vietnam’s urban centers. Between 1986 and 1996—a decade coinciding with the ‘Doi Moi’ economic reforms that sparked a construction boom—Hanoi lost nearly two-thirds of water bodies in its four core urban districts, according to research from Kyoto University’s Center for Southeast Asian Studies.

More recently, between 2015 and 2020, the city lost water bodies covering an area equivalent to 285 soccer fields, according to state media reports.

A 2024 study found that more than three-quarters of Hanoi’s total area—including much of its densely populated core—faces significant flood risk. Hong Ngoc Nguyen, lead author of the study and environmental engineer at Japanese consultancy Nippon Koei, explains that flooding in Hanoi can’t be solved merely by building more infrastructure.

“We can’t control the water,” she said, pointing to Singapore’s transition from concrete canals to greener riverbanks that slow and retain stormwater rather than rushing it away.

Global Solutions Through Natural Design

The concept of designing cities to “live with water” is gaining momentum globally, including in Vietnam. Similar efforts are underway in India’s Bengaluru, where officials and residents are working to preserve the city’s remaining lakes, while South Africa’s Johannesburg is attempting to restore its Jukskei River.

Vietnam’s recent floods have catalyzed broader discussions about urban responses to extreme weather events. Ngo Trung Hai, former director of the National Institute of Urban and Rural Planning, told the state-run Hanoi Times that the city must learn to coexist with heavy rainfall and adopt long-term adaptive strategies. European business associations have urged Ho Chi Minh City to implement “sponge city” approaches.

Real estate developers have faced criticism in state media for practices like building on low-lying land, constructing roads unconnected to storm sewer systems, and treating water bodies as decorative “landscape features” rather than functional drainage systems.

Some of Vietnam’s largest property developers have begun adapting their approaches. In the coastal tourism center of Nha Trang, Sun Group is developing a new township based on “sponge city” principles, incorporating 60 hectares (148 acres) of wetlands designed to store and reuse rainwater to mitigate flooding and reduce heat absorption.

Anna Beswick, who studies climate adaptation at the London School of Economics, emphasizes that city planners must account for future climate risks rather than past patterns.

“If we plan based on past experience, we won’t be resilient in the future,” she warned.