Ho Chi Minh City plans $7M underground reservoir beneath football field to fight flooding

The underground reservoir would be able to store 13,000 cubic meters of rainwater, the equivalent of 650 large tanker trucks, and help prevent streets from being submerged after heavy rains, usually by up to two meters.

According to the Thu Duc Infrastructure Development Center, the city's terrain is shaped like a basin with an elevation gap of nearly 30 meters, which causes rainwater from higher areas to flow into Thu Duc. Combined with an aging, silted-up drainage system, this has left the area repeatedly inundated, especially along To Ngoc Van, Pham Van Dong, Duong Van Cam and around Thu Duc Market. For years, the area has been known as a "flooding basin" of the city.

The underground reservoir would be built beneath the football field at 16 Tran Van Nua Street, measuring 70 by 50 meters with a depth of 5.2 meters. It would be constructed using modular hollow plastic panels known as Cross-wave.

The project, expected to cost VND178 billion (US$7 million), also includes a settling pond, a pumping chamber, collection pipes and drainage outlets. Once completed, the football field would be restored for sports and recreation.

City officials say the underground design makes the most of space beneath public facilities such as football fields, parks and schools. Besides easing flooding, it could also store water for firefighting and irrigation. Experts note this land-saving approach has been widely applied in cities like Singapore and Tokyo, where space is limited and climate challenges are pressing.

If approved, the Linh Tay reservoir would be 130 times larger than the underground reservoir built in 2017 on Vo Van Ngan Street, in front of Thu Duc’s Children’s Cultural House, with assistance from Japan.

Vo Kim Cuong, former deputy chief architect of HCMC, said building underground reservoirs beneath sports fields integrates multiple functions within one space.

"If we only use the ground surface, we're only tapping into a third of the city's spatial potential," he said. Still, he warned that underground reservoirs are expensive, requiring strong structural systems to return usable ground above, and costing far more than open lakes or renovated natural ponds.

HCMC had previously set a target of building seven regulating reservoirs as part of its flood-control plan, including six underground projects and the 20-hectare Go Dua open reservoir in Thu Duc, with a total budget of more than VND1 trillion. But so far, these projects have stalled due to technical standards and lack of funding.

In addition to the Linh Tay proposal, Thu Duc authorities are also urging the development of the Ngoc Thuy canal drainage system in Truong Tho Ward. This would ease the load on Vo Van Ngan Street by channeling water into the Nha Tra and Thu Duc canals. Officials have also called for dredging and embankment work on Thu Duc canal, and for the installation of a pumping station with a capacity of 120,000 cubic meters per hour to boost drainage for the entire district.