To complete the flood protection system for the inner city, two more sluice gates must be built alongside those included in the US$400 million project. Both were proposed in the city's flood control master plan in 2008, but have yet to be implemented due to funding constraints.
Nguyen Phu Quynh, Deputy Director of Southern Institute of Water Resources Research (SIWRR), said: "We need to build the Vam Thuan and Rach Nuoc Len sluice gates to complete flood protection for the 57,000-hectare area. Equally important is developing a coordinated operating procedure to ensure all these structures work together effectively".
For the next phase of flood control to be properly planned and avoid overlapping investments, the city also needs a reliable and comprehensive hydrological database. This means identifying exactly which areas are most severely affected and distinguishing between rainfall-induced and tidal flooding.
Pham Hoai Trung, Deputy Head of Technical Infrastructure Planning Division, HCMC Department of Planning and Architecture, said: "To determine which areas should be prioritised, we need further research, particularly more detailed hydrological studies. The city currently lacks a comprehensive hydrological map to serve as a basis for calculations and for developing specific, detailed solutions for each project".
This is an urgent issue, as the hydrological reference levels at Phu An and Nha Be monitoring stations were established back in 2008. Meanwhile, Nha Be has experienced continuous land subsidence over nearly two decades.
The rise in tidal water levels must also be reassessed to identify the contributions of land subsidence, groundwater changes and land reclamation.
Accurate data will help the city pinpoint the causes of flooding and prioritise future investments, including whether to build an additional Saigon sluice gate to prevent floodwaters from reaching the inner city.
