Ho Chi Minh City reduces groundwater extraction to fight land subsidence

He identified four main factors behind severe land subsidence in the city, including weak geological foundations in southern areas, declining groundwater levels, transportation and construction activities, and rapid urbanization.

While some causes of subsidence, such as geological conditions, construction-related stress and urbanization, require long-term solutions, groundwater depletion is one area where the city can take more immediate and decisive action.

Decades of excessive groundwater extraction in the city have led to serious environmental consequences.

As such, protecting the groundwater has become an urgent priority.

Groundwater is stored in pockets between geological layers, and when it is pumped out faster than it can be naturally replenished, these voids remain unfilled.

Over time, the ground above can collapse into these empty spaces, leading to subsidence, which is hitting several parts of the city.

Recognizing the urgency, the municipal People’s Committee introduced Decision No. 1242 in 2018, outlining a roadmap to reduce groundwater usage and seal unused wells by 2025.

The Saigon Water Corporation (SAWACO) said that firms and residents are the two main groups using groundwater.

Meanwhile, SAWACO has been systematically sealing wells that are no longer in use, aligning with the city’s broader goals.

The firm reported that while many households are connected to the public water supply system, a significant number do not utilize it.

Instead, they continue to rely on private wells, especially in outlying areas.

For instance, water usage reports showed that in Di An Ward, part of former Binh Duong Province, 11.13 percent of households recorded zero cubic meters of usage on their water bills.

Similarly, in former Hoc Mon and Binh Chanh Districts, 10.15 percent and 9.29 percent of households, respectively, reported no water consumption.

To further curb groundwater extraction, the city approved zoning maps that designate restricted and prohibited areas for underground water use.

As of the end of 2024, Ho Chi Minh City had succeeded in reducing groundwater extraction from 716,581 cubic meters per day to 252,528 cubic meters per day, bringing the city closer to its 2025 goal of just 100,000 cubic meters per day.