The Maritimepattu Divisional Secretariat (DS), located in Sri Lanka’s dry zone, is underlain by Miocene limestone, which is considered to have aquifer properties favourable for groundwater storage and discharge. Given that groundwater serves as the primary water resource for domestic, industrial, and agricultural purposes, maintaining its quality is a significant concern. This paper aims to assess the water quality in the region, identify associated problems, and investigate potential causes and preventive measures. A purposive sampling method was employed to select six sample Grama Niladhari (GN) divisions. In addition, 100 questionnaires were administered, and 36 water samples were collected for the study. These water samples were tested based on eight major water quality parameters: Electrical Conductivity (EC), Salinity, pH, Total Dissolved Solids (TDS), Fluoride (F-), Nitrogen (N), Phosphorous (P), and Turbidity (Tn). Furthermore, secondary data were gathered from previous literature. Both primary and secondary data were analysed using Minitab and Geographic Information Systems (GIS). The measurements were then compared to the desirable limits set by the Sri Lanka Standards Institute (SLSI). This study revealed that the highest recorded values for EC, Salinity, pH, TDS, F-, N, P, and Tn were 2480 µS/cm, 1254 ppm, 8.6, 632 ppm, 1.1 ppm, 7,9 ppm, 3.8 ppm, and 36.7 NTU, respectively. These values exceed the standard limits set by the Sri Lanka Standards Institute (SLSI). The pollution in the area can be attributed to various factors, including topographical conditions, improper agricultural practices, inadequate sanitation methods, dumping sites, war activities, and industrial waste. As a result, these issues have led to serious health problems, reduced crop yields, insufficient drinking water, and the degradation of groundwater resources. Therefore, this study recommends the adoption of green agriculture practices, the installation of water treatment plants, the promotion of rainwater harvesting systems, and the enforcement of land and irrigation-related laws. Moreover, hazardous waste material must be disposed of at designated sites to protect water resources.