The Department of Science and Technology of Ho Chi Minh City has just organized an Advisory Council to accept the task from the S&T, known as “Research and evaluate the situation of saltwater intrusion when operating tidal sluices under the project to solve tidal flooding in Ho Chi Minh City area taking into account climate change factors” chaired by the International University – Ho Chi Minh City National University, Assoc. Prof. Dr. Pham Ngoc as the head.

The mission was deployed with the aim of assessing potential damage caused by saltwater intrusion to water supply activities in Ho Chi Minh City in the context of increasingly complex climate change.

Overview of the acceptance ceremony

Ho Chi Minh City is a large urban area located in the lower reaches of the Dong Nai River, with low terrain, strongly affected by the East Sea tide and the trend of global climate change. In recent years, high tides, heavy rains and flooding have increased, while in the dry season there has been deep saline intrusion, causing the raw water source for daily life and production to be constantly threatened. In particular, the preparation for putting into operation the system of six tidal sluices is expected to change the hydrodynamic regime on the rivers, requiring a scientific, objective and comprehensive assessment to forecast the impact, proactively manage and ensure water security for the City. This is the important basis for the implementation of the task.

According to Associate Professor Dr. Pham Ngoc, the mission has collected field data on water levels, flow and salinity in rivers, canals and streams in the Ho Chi Minh City area, combined with historical data to assess the development of saltwater intrusion under the operating conditions of the tidal sluice system under the Tidal Flooding Resolution Project. The results of the 2023 dry season survey show that saltwater intrusion fluctuates strongly according to the tidal regime, the amount of water from upstream and the level of operation of the project, providing reliable data for simulation and scientific evaluation.

Associate Professor, Dr. Pham Ngoc – Head of the task presented at the council

The study simulated many scenarios of tidal sluice gate operation in conjunction with historical drought and salinity scenarios and climate change (RCP8.5), thereby determining the trend of salinity spread, changes in salinity and water levels at sensitive locations such as Nha Be, Phu An and Ong Lon. The results showed that sluice gate operation has the effect of reducing salinity in some inner-city areas but at the same time can increase salinity intrusion downstream in the dry season, especially when upstream flow decreases. This requires flexible regulation when operating the flood control system.

Based on the analysis results, the task proposed comprehensive solutions including engineering and non-engineering solutions and recommendations for operating the sewer system combined with water resource management. The solutions aim to minimize the adverse impacts of saline intrusion on domestic water supply, industry and agricultural production, contributing to ensuring water security and sustainable development for the City. At the same time, the study provides scientific arguments for planning policies for operating the project in the context of climate change and the need to balance between flood prevention and water quality protection.

With the results achieved, the Science and Technology Council has unanimously accepted the topic. However, it is necessary to edit and complete the topic according to the suggestions of the council members.

Source: Center for Science and Technology Information and Statistics