Assessment and zoning of self-cleaning ability of urban inner canal group in Ho Chi Minh City

Abstract

The rapid urbanization of Ho Chi Minh City (HCMC) is a huge pressure upon the surface water quality as well as its self-cleaning capacity. Every day, a large amount of domestic wastewater is discharged directly into the canal system with concentrations of toxic pollutant components. The assessment of the quality and self-cleaning capacity of canal water by the oxy declining process is a basic foundation for the planning and management of waste water drainage and treatment system in the City. With the application of oxy declining and osmotic experiential coefficient formulas into the oxidation process equation (Streeter-Phelpse), the self-cleaning capacity are determined and classified at any time and positions. The self-cleaning capacity depended on the hydraulic and quality condition of canals. The research of self-cleaning capacity is implemented for urban inner canal system of HCMC in the period 2012 – 2021. Based on the assessment’s results, the distribution of self-cleaning capacity levels is mapped to analyse the changes and zone. The zoning maps expressed suitability the distribution levels of self-cleaning capacity with high visualization. And they are a valuable basis for planning and decision making on the solutions to improve environment quality of the relative management agencies of HCMC.