3. Assessment of groundwater quality using groundwater quality index in Chau Thanh commune, Vinh Long province

Abstract

Chau Thanh commune, Vinh Long province (formerly Chau Thanh district, Tra Vinh province) is a water-scarce area according to Decision No. 1553/QD-TTg dated November 8, 2019 of the Prime Minister on the program to investigate and search for groundwater resources to supply domestic water in highland areas and water-scarce areas. During the dry season, the area faces water scarcity due to saltwater intrusion and depletion of groundwater resources due to overexploitation. Therefore, it is critical to evaluate the quality of groundwater to serve research and propose solutions for exploiting groundwater resources for domestic water supply, ensuring social security and economic development in the region. The study evaluated the Groundwater Quality Index (GWQI) for the middle-upper Pleistocene aquifer (q2-3) through the following parameters: pH, total hardness, Cl⁻, SO₄²⁻, NO₃⁻, NO₂⁻, NH₄⁺, Fe, As, and Coliform. The results indicated that groundwater quality in the study area can be classified into three categories: poor (4.4 % of total samples), moderate (15.5 %), and good (80 %).