Assessment of Groundwater Quality in Water-Scarce Areas of Tay Ninh Province Using Water Quality Indices
Main Article Content
Abstract
Water quality indices are widely used around the world and in Vietnam to assess the quality of water for domestic use and industrial use. In this paper, we apply the Groundwater Quality Index (GWQI), the Composite Pollution Index (CPI), and the Heavy Metal Pollution Index (HPI) to assess groundwater quality in the Early Pliocene aquifer (n21) in water-scarce communes in Tay Ninh province for domestic use (including parameters: pH, TDS, hardness, Cl⁻, SO₄²⁻, NO₃⁻, NO₂⁻, NH₄⁺, Fe, As, Pb, Mn, and coliform). The results of a study on 49 groundwater samples, conducted from October 26, 2022, to November 20, 2022, indicate that groundwater quality according to the GWQI is classified into two categories: medium (accounting for 6.1% of the total samples) and good (93.9%); according to the CPI, groundwater quality is classified as clean (6.1%) and very clean (93.9%); according to the HPI, the results show that 100% of the samples are not contaminated by heavy metals. In most boreholes, the groundwater is good quality for domestic use; however, some sampling locations have TDS and coliform levels exceeding the standards and therefore require treatment before use. The study also demonstrates that water quality indices can provide a relatively reliable indicator of groundwater quality, thereby supporting improved planning, management, and exploitation of water resources and contributing to sustainable water resource development.
Keywords:
Water - scarce area, water quality index, GWQI, CPI, HPI, Tay Ninh province.
References
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[3] L. T. T. Tam, D. X. Phong, T. P. Dung, The Current State of Degradation, Pollution of Groundwater in Quaternary Sediments in the Thai Binh Province, Vietnam Journal of Earth Sciences, Vol. 35, Iss. 4, 2013, pp. 387-394.
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[7] N. T. Giao, H. T. H. Nhien, P. K. Anh,
P. Thuptimdang, Groundwater Quality Assessment for Drinking Purposes: A Case Study in the Mekong Delta, Vietnam, Scientific Reports,
Vol. 13, Iss. 1, 2023, https://doi.org/10.1038/s41598-023-31621-9.
[8] D. T. N. Tuyen, H. M. Hoang, N. H. Tan, D. T. Truc, V. P. D. Tri, Assessing the Changes in Groundwater Quality in Ca Mau Province, Can Tho University Journal of Science, Vol. 61, 2025, pp. 211-222, https://doi.org/10.22144/ctujos.2025.071
(in Vietnamese).
[9] R. Reza, G. Singh, Assessment of Groundwater Quality Status by Using Water Quality Index Method in Orissa, India, World Applied Sciences Journal, Vol. 9, Iss. 12, 2010, pp. 1392-1397.
[10] Q. Zhang, H. Qian, P. Xu, K. Hou, F. Yang, Groundwater Quality Assessment Using a New Integrated-weight Water Quality Index (IWQI) and Driver Analysis in the Jiaokou Irrigation District, China, Ecotoxicology and Environmental Safety, Vol. 212, 2021, https://doi.org/10.1016/j.ecoenv.2021.111992.
[11] D. D. Phuc, N. T. Tuan, Using the VISUAL MODFLOW Model to Determine the Flow Rates and Operational Regimes of Injection and Extraction Wells, Environment Magazine, Iss. 4, 2025, pp. 52-57 (in Vietnamese).
[12] X. Wang, X. B. Gu, H. Zhang, The Water Quality Assessment of Groundwater Based on the TOPSIS-GRA, Polish Journal of Environmental Studies, Vol. 35, Iss. 2, 2026, pp. 2859-2870, https://doi.org/10.15244/pjoes/202604.
[13] K. Mahamadou, T. Adama, C. Wendpagnagda, Z. I. Eulodie, B. O. Y. L. Ibrahim, A. M. Hassan, Groundwater Quality Assessment and Modeling Using Water Quality Index and Mathematical Models: Case Study of Bam Province, Burkina Faso, International Journal of Environment and Climate Change, Vol. 14, Iss. 12, 2024, pp. 740-756, https://doi.org/10.9734/ijecc/2024/v14i124659.
[14] T. Poonam, B. Tanushree, C. Sukalyan, Water Quality Indices - Important Tools for Water Quality Assessment: A Review, International Journal of Advances in Chemistry, Vol. 1, Iss. 1, 2013, pp. 15-28.
[15] P. Li, Abbasi T and Abbasi SA: Water Quality Indices, Environmental Earth Sciences, Vol. 71, Iss. 10, 2014, pp. 4625-4628, https://doi.org/10.1007/s12665-014-3141-9.
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pp. 33-37.
[18] N. M. Anh, N. T. Hang, B. T. Huyen, N. H. My, C. T. Hue, C. T. Son, Assessment of An Duong Lake Water Quality in Hai Duong Province Using a Water Quality Index and Water Pollution Indices, TNU Journal of Science and Technology, Vol. 225, Iss. 9, 2020, pp. 39-46 (in Vietnamese).
[19] S. V. Mohan, P. Nithila, S. J. Reddy, Estimation of Heavy Metals in Drinking Water and Development of Heavy Metal Pollution Index, Journal of Environmental Science and Health, Part A: Environmental Science and Engineering and Toxicology, Vol. 31, Iss. 2, 1996, pp. 283–289, https://doi.org/10.1080/10934529609376357.
[20] S. Tavassoli, F. Mohammadi, Groundwater Quality Assessment Based on WQI and Its Vulnerability to Saltwater Intrusion in a Coastal City, Iran, Journal of Geoscience and Environmental Protection,
Vol. 5, Iss. 6, 2017, pp. 88-98, https://doi.org/10.4236/gep.2017.56010.
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[22] N. T. Ha, T. V. Hoan, N. T. Thao, N. T. Hoa, M. C. Thanh, Decline Trend of Groundwater Level in the Mekong River Delta Plain, Journal of Climate Change Science, Iss. 16, 2020, pp. 25-34 (in Vietnamese).
[23] P. V. Hung, F. C. Van Geer, T. B. Vuong, W. Dubelaar, G. H. P. Oude Essink, Paleo-Hydrogeological Reconstruction of the Fresh-Saline Groundwater Distribution in the Vietnamese Mekong Delta Since the Late Pleistocene, Journal of Hydrology: Regional Studies, Vol. 23, 2019, https://doi.org/10.1016/j.ejrh.2019.100594.
[24] Vietnam National Standard 6663-11:2011 (ISO 5667-11:2009), Water Quality - Sampling - Part 11: Guidance on Sampling of Groundwaters, 2011 (in Vietnamese).
[25] Vietnam National Standard 6663-3:2016 (ISO 5667-3:2012), Water Quality - Sampling - Part 3: Preservation and Handling of Water Samples, 2016 (in Vietnamese).
[26] Vietnam National Standard 6663-1:2011 (ISO 5667-1:2006), Water Quality - Sampling - Part 1: Guidance on the Design of Sampling Programmes and Sampling Techniques, 2011 (in Vietnamese).
[27] Vietnam National Standard 6663-14:2000 (ISO 5667-14:1998), Water Quality – Sampling - Part 14: Guidance on Quality Assurance of Environmental Water Sampling and Handling, 2000 (in Vietnamese).
[28] Ministry of Natural Resources and Environment, Vietnam National Technical Regulation 09:2023/BTNMT - National Technical Regulation on Groundwater Quality, 2023 (in Vietnamese).
[29] General Department of Environment, Ministry of Natural Resources and Environment, Decision Number 1460/QĐ-TCMT dated 12/11/2019 Regarding the Issuance of the Technical Guidelines for Calculating and Publishing the Vietnam Water Quality Index (VN_WQI), 2019 (in Vietnamese).
[30] R. M. Brown, N. I. McClelland, R. A. Deininger, M. F. O’Connor, A Water Quality Index - Crashing the Psychological Barrier, In W. A. Thomas (Ed.), Indicators of environmental quality, Vol. 1, 1972, pp. 173-182,
https://doi.org/10.1007/978-1-4684-2856-8_15.
[31] G. Y. Lu, D. W. Wong, An Adaptive Inverse-Distance Weighting Spatial Interpolation Technique, Computers & Geosciences, Vol. 34, Iss. 9, 2008, pp. 1044-1055, https://doi.org/10.1016/j.cageo.2007.07.010.