Drinking water from various sources in Bangladesh’s coastal region has become polluted with diverse degrees of salinity due to saltwater intrusion from increasing sea levels, cyclone and storm surges, and upstream loss of fresh water. Salinity intrusion poses threats to water standard and security, as well as the health of people. The present study was conducted in coastal Dacope Upazila (sub-district) in southwestern Bangladesh to evaluate the impacts of salinity intrusion on human health. Data on some chronic illnesses such as arsenicosis, diarrhoea, as well as tuberculosis were collected from Dacope Upazila Health Complex for the period of 2013–2019. Environmental parameters comprising total dissolved solids (TDS), total solids (including both dissolved and suspended solids) (TS), acidity-alkalinity (pH), biological oxygen demand (BOD), iron (Fe), chemical oxygen demand (COD), electrical conductivity (EC), salinity, arsenic (As), and groundwater table data were also collected. T