Ho Chi Minh City faces risk of becoming one of world’s fastest sinking cities

Ho Chi Minh City is facing accelerating land subsidence and growing flood risks, placing it at risk of becoming the second most threatened among the world’s ten fastest sinking cities, local authorities warned on Thursday.

The office of surveying, mapping and remote sensing under the city’s Department of Agriculture and Environment issued the warning in a report presented at a meeting on the city’s socio-economic performance.

According to the agency, several factors are driving the subsidence, including weak geological foundations, heavy traffic loads, dense construction, rapid urbanization and continued groundwater extraction.

By late 2019, visible sinking had appeared across large parts of the city.

The deepest recorded subsidence reached 31mm.

Areas sinking more than 15mm per year covered about 14,775 hectares, while zones sinking 10 to 15mm per year spanned 22,331 hectares.

Another 29,560 hectares experienced annual subsidence of 5 to 10mm.

The office warned that these trends could place the city as the world’s second fastest sinking urban center.

A long-term study by the Japan International Cooperation Agency (JICA) found that subsidence has continued steadily since 1990, with total accumulated sinking now estimated at around 100cm.

Current rates range from 2 to 5cm per year, and can reach 7 to 8cm in dense commercial clusters.

These rates are about double the pace of sea level rise, which averages roughly one centimeter per year.

Officials said the combined impact of sinking ground, tidal flooding and rising seas is steadily increasing the city’s vulnerability and could undermine long term development.

Though gradual, subsidence becomes far more dangerous when coupled with climate change, extreme weather and higher tides.

In response, the city is ramping up monitoring, simulation and forecasting to develop appropriate adaptation measures.

A new center is being established to this end, providing long-term support for socio-economic, urban, and environmental planning.

Following instructions from the municipal administration, the Department of Agriculture and Environment is also working with JICA on a draft technical assistance project to advance subsidence response solutions.

Together with an ongoing program by the Department of Science and Technology on ground deformation forecasting, the project aims to provide a comprehensive assessment of subsidence causes and guide long term mitigation strategies.

In parallel, the department is upgrading the city’s grade-IV elevation benchmark system for 2025 to 2026.

The improved system will support urban planning, climate adaptation, national defense planning and detailed evaluation of subsidence patterns across the city.

By Vinh Tho & Chau Tuan – Tuoi Tre News – November 14, 2025