The project, led by Assoc. Prof. Bùi Việt Hưng, focused on assessing the self-cleaning capacity of water sources in the urban canals of Ho Chi Minh City, taking into account the impact of tide control system operations and climate change. The study aimed to improve water quality management and proposed solutions, such as enhancing wastewater treatment and completing urban rehabilitation projects along the canal routes.

On 18 February, at the University of Science, Viet Nam National University Ho Chi Minh City (VNUHCM), the VNUHCM Scientific and Technological Project Evaluation Council held a meeting to assess and evaluate the project titled “Assessing the Self-Cleaning Capacity of Water Sources in Ho Chi Minh City’s Urban Canals, Considering the Impact of Tide Control System Operations and Climate Change.” The project was led by Assoc. Prof. Bùi Việt Hưng, Project Leader and Vice Head of the Department of Environmental Management and Informatics at the Faculty of Environment, and his team, which included MSc. Phạm Thị Hà (Secretary), MSc. Phạm Việt Hải, and Dr. Lê Hoàng Anh.

Current Pollution Status and Water Management Solutions in Ho Chi Minh City’s Canal System

Ho Chi Minh City has an extensive system of rivers, canals, and ditches, with the length of the urban canal system measuring approximately 76 km. This system, along with the Saigon River, plays a significant role in draining water for the city and receiving wastewater from various socio-economic activities within the catchment area. However, the urban canal system has been severely polluted, primarily by industrial, medical, and over 1.7 million cubic metres per day of untreated domestic wastewater, which is directly discharged into the canals. The concentration of pollutants in the canal system often exceeds the permissible standards (QCVN 08:2023/BTNMT) by 2-5 times, and in some cases, by 10-20 times.

The city’s authorities have made efforts to control environmental quality, particularly water quality, through annual water quality monitoring and the implementation of canal and ditch rehabilitation projects. These projects included the removal and relocation of makeshift housing, dredging to improve flow, and enhancing water exchange with the Sai Gon River. After rehabilitation, both the water quality and self-cleaning capacity of the canals improved. However, management and project implementation still faced some challenges, such as inconsistent monitoring data, lack of continuity, and a heavy reliance on annual budgets. Over time, the water quality showed signs of deterioration due to a lack of consistency and incomplete project components.

Research Methods and Approach

The project employed multivariate regression interpolation and empirical curve fitting using high-degree polynomials to improve the continuity and representation of the water quality dataset for the urban canal system from 2012 to 2022. Missing quality components were added, and non-continuously monitored locations were incorporated.

The study applied an adjusted Water Quality Index (WQI) and the Streeter-Phelps equation to analyse trends in the self-improvement of water quality in the urban canal system of Ho Chi Minh City. The research also considered climate change scenarios and the operation of the tide control system.

Research Findings

The results indicated that the trend of water quality improvement in the urban canals was moderate and dependent on the level of water exchange with the Saigon River through tidal flows. When 100% of domestic wastewater was treated to meet QCVN 08:2023/BTNMT standards, the trend for water quality improvement was positive. The study also identified that the tide control gates primarily affected the system during the construction phase, with no significant impact during the operational phase.

Based on the water quality trend analysis, the project proposed environmental management solutions, including the completion of urban rehabilitation projects along the canal routes and enhancing wastewater collection and treatment to achieve the goal of a clean, green urban environment.

In addition to the research findings, the team achieved notable milestones, including one Scopus-indexed publication and the successful defence of a master’s thesis by one student.

Minh Tâm _ Translated by ℙ𝕄ℕ