Characteristics on distribution of chemical composition in groundwater along the Mekong and Bassac (Hậu) river, Vietnam


  • Hikaru Sato Graduate School of Symbiotic Systems Science and Technology, Fukushima University, 1 Kanayagawa, Fukushima City, Fukushima 960-1296, Japan
  • Naoaki Shibasaki Faculty of Symbiotic Systems Science, Fukushima University
  • Nguyen Van Lap Ho Chi Minh City Institute of Resources Geography, Vietnam Academy of Science and Technology
  • Ta Thi Kim Oanh Ho Chi Minh City Institute of Resources Geography, Vietnam Academy of Science and Technology
  • Nguyen Thi Mong Lan Ho Chi Minh City Institute of Resources Geography, Vietnam Academy of Science and Technology



Dissolved ions, trace elements, groundwater quality distribution, the Mekong River, the Bassac (Hậu) River


Along the Mekong River (MR), arsenic contamination in the groundwater has been recognized since the 2000s. Due to arsenic contamination in shallow aquifers, the drinking water has been prevented from being contaminated with arsenic by installing wells, 200 m to 400 m deep. However, it has been known that groundwater was contaminated by not only arsenic but also other trace elements. The need to reveal characteristics on the distribution of chemical composition by horizontally and vertically is increasing for purposes of appropriate development and management of groundwater. This study summarized the results of surveys for arsenic since 2008 and surveys for dissolved ions and trace elements since 2015, and described characteristics on distribution for chemical composition at the regional areas along the MR and Bassac (Hậu) River (BR). Groundwater samples were collected from existing wells in 8 provinces and 1 city. The authors used Piper and Stiff diagram that reflect the chemical composition of groundwater to respond to varying horizontal and vertical distributions. The Principal Component Analysis (PCA) was also carried out to reveal the correspondences of dissolved ions and trace elements. Variety concentrations and distributions of ions and trace elements show the obvious distinction between upper (<200 m deep) and lower (>200 m deep) aquifers broadly divided by geologic age. A wide variety of ion compositions and trace elements was found in the upper aquifer, and concentration of some trace elements in groundwater was high and exceed the World Health Organization (WHO) drinking water guideline value. On the other hand, groundwater in the lower aquifer is simple and rarely contaminated by trace elements. However, the arsenic concentration ranging from 0.01–0.065 mg/L slightly exceeding the WHO guideline value was found at the lower aquifer in the downstream areas of the Mekong River Delta. These results on the distribution analysis provide the insight that deep groundwater is not necessarily safe by over-pumping from deep aquifer and drilling new wells in the downstream areas.


Download data is not yet available.


AAN and Research Group for Groundwater Contamination by Arsenic in the Mekong River Delta (Mekong Group), 2012. Groundwater arsenic contamination in the Mekong River Delta. The Association for the Geological Collaboration in Japan (AGCJ), 151pp. (in Japanese, English and Vietnamese)

Appelo C.A.J., Postma D., 2005. Geochemistory, groundwater and pollution (2nd ed.). Rotterdam: A.A.Balkema Publishers, 649pp.

Berg M., Stengel C., Pham T.K.T., Pham H.V., Sampson M.L., Leng M., Samreth S. and Fredericks D., 2007. Magnitude of arsenic pollution in the Mekong and Red River Deltas-Cambodia and Vietnam. Science of the Total Environment, 372, 413–425.

Buschmann J., Berg M., Stengel C., Winkel L., Sampson M.L., Pham T.K.T., Pham H.V., 2008. Contamination of drinking water resources in the Mekong delta floodplains: Arsenic and other trace metals pose serious health risks to population. Environment International, 34, 756–764.

Erban L.E., Gorelick S.M., Zebker H.A., Fendorf S., 2013. Release of arsenic to deep groundwater in the Mekong Delta, Vietnam, linked to pumping induced land subsidence. Proceedings of the National Academy of Sciences of the United States of America (PNAS), 110, 13751–13756.

Fabrice G.R., Claudia K., 2012. The Mekong Delta System Interdisciplinary Analyses of a River Delta. Springer Environmental Science and Engineering, Springer Netherlands, 463pp.

General Statistics Office Of Vietnam (GSO), 2016. Population and Employment, Statistical Yearbook of Vietnam 2015. Statistical Documentation and Service Centre General Statistics office of Vietnam,,(Access, 2018/9/6).

Hironaka H., 1998. On site analysis of As3+ and As5+ by mercury bromide paper disk colorimetry method (Gutzeit method modified by Hironaka). Annual Report of Fukuoka City Institute for Hygiene and Environment, 23, 120–122. (in Japanese with English abstract)

Hoang T.H., Bäumle R., 2019. Complex hydrochemical characteristics of the Middle-Upper Pleistocene aquifer in Soc Trang Province, Southern Vietnam. Environmental Geochemistry and Health, 41, 325–341.

Hoang T.H., Bang S., Kim K-W., Nguyen M.H., Dang D.M., 2010. Arsenic in groundwater and sediment in the Mekong River delta, Vietnam. Environmental Pollution, 158, 2648–2658.

Ito T., Sato H., Shibasaki N., 2016. Groundwater arsenic and extent of contamination along the Mekong River, Vietnam. Arsenic Research and Global Sustainability (As2016), CRC Press, 70–71.

Merola R.B., Hien T.T., Quyen D.T.T., Vengosh A., 2015. Arsenic exposure to drinking water in the Mekong Delta. Science of the Total Environment, 511, 544–552.

Minderhoud P.S.J., Erkens G., Pham V.H., Bui V.T., Erban L., Kooi H., Stouthamer E., 2017. Impacts of 25 years of groundwater extraction on subsidence in the Mekong delta, Vietnam. Environmental Research Letters, 12, 064006.

Ministry of Health, 2009. National technical regulations on drinking and domestic water quality. Report nr, 04/2009/TT-BYT, Hanoi, Vietnam. Socialist Republic of Vietnam. Ministry of Health General Department of Preventive Medicine & Environment, 9pp.

Nguyen K.P., Itoi R., 2009. Source and release mechanism of arsenic in aquifers of the Mekong Delta, Vietnam. Journal of Contaminant Hydrology, 103, 58–69.

Nguyen V.L., Ta T.K.O., Nguyen V.D., 2008. Recent situation of arsenic contamination in groundwater in Dong Thap province and its countermeasures. Technical Report, 98pp.

Nguyen V.L., Ta T.K.O., Tateishi M., 2000. Late Holocene depositional environments and coastal evolution of the Mekong River Delta, Southern Vietnam. Journal of Asian Earth Sciences, 18, 427–439.

Nickson R.T., McArthur J.M., Ravenscroft P., Burgess W.G., Ahmed K.M., 2000. Mechanism of arsenic release to groundwater, Bangladesh and West Bengal. Applied Geochemistry, 15, 403–413.

Shinkai Y., Truc D.V., Sumi D., Canh D., Kumagai Y., 2007. Arsenic and other Metal Contamination of Groundwater in the Mekong River Delta Vietnam. Journal of Health Science, 53, 344–346.

Tran D.A., Tsujimura M., Vo L.P., Kawauchi A., Doan T.H., 2014a. Chemical Characteristics of Surface Water and Groundwater in Coastal Watershed, Mekong Delta, Vietnam. The 4th International Conference on Sustainable Future for Human Security, SustaiN 2013. Procedia Environmental Science, 20, 712–721.

Tran D.A., Tsujimura M., Vo L.P., Truong T.H., 2014b. Groundwater Flow System in Coastal Region of the Mekong Delta as Determined by Hydrogeochemistry. Proceeding of the 19th IAHR-APD Congress 2014, Hanoi, Vietnam ISBN 978604821338-1, 7pp.

Wilkie J.A., Hering J.G., 1996. Adsorption of arsenic onto hydrous ferric oxide: effects of adsorbate/adsorbent ratios and co-occurring solutes. Colloids and Surfaces, 107, 97–110.

World Health Organization, 2011. Guidelines for Drinking-water Quality Fourth Edirion, 541pp.


How to Cite

Sato, H., Shibasaki, N., Lap, N. V., Oanh, T. T. K., & Lan, N. T. M. (2019). Characteristics on distribution of chemical composition in groundwater along the Mekong and Bassac (Hậu) river, Vietnam. Vietnam Journal of Earth Sciences, 41(3), 272–288.




Most read articles by the same author(s)