Impacts of seawater intrusion on groundwater quality in Htantabin township of the deltaic region of southern Myanmar

Abstract

Climate change and extensive groundwater extraction threaten the sustainability of groundwater resources in Myanmar, especially in the Ayeyarwaddy Delta region. Due to the lack of public water supply, an increasing population with extensive agricultural and industrial development has raised the importance of groundwater in many areas of the Ayeyarwaddy Delta. This study revealed the suitability of groundwater quality for drinking and irrigation purposes and the selection of piping materials in the Htantabin township of the delta region, which belongs to the highest group of water consumption from unimproved sources. Seasonal quality changes in groundwater and the influencing factors were also studied. The findings showed that groundwater in some locations in the study area was contaminated by saltwater. Areas within 100 m of the irrigation canal were more likely to experience seawater intrusion. The majority of groundwater samples were not suitable for drinking as the examined parameters exceeded the WHO guideline values. In the summer, only 37.5% of groundwater samples were fitted into categories that were suitable for irrigation; however, a higher percentage (62.5%) became suitable during the rainy season with a reduction in salinity. Contrary to groundwater salinity, the corrosion risk for metal pipes increased during the rainy season.