http://drw.jfn.ac.lk/handle/123456789/61 Tue, 12 May 2026 16:17:09 GMT 2026-05-12T16:17:09Z http://drw.jfn.ac.lk/handle/123456789/430 Assessment and mapping of groundwater quality for drinking purposes: A case study on Vallipuram coastal area, Jaffna peninsula, Sri Lanka. Sharmilaa, R.; Anoja, N.; Sirisena, K. A. The people of the Jaffna Peninsula completely rely on groundwater for all of their water requirements. The Vallipuram water supply scheme has been started by National Water Supply & Drainage Board (NWS&DB) with the construction of four groundwater wells in the Vadamarachchi sand dune aquifer. However, due to the over-extraction of groundwater from these wells, there could be a severe groundwater imbalance in the area, where aquifers are depleting and the water table is lowering. Therefore, the present study was designed to identify the availability and quality of the well water surrounding a 1.5 km radius from the four NWS&DB dug wells, and 120 domestic wells were selected for the study. This study aims at the assessment and mapping of groundwater quality parameters and assessing the Water Quality Index (WQI) to determine the potability of groundwater. Sample collection and water quality analyses were conducted according to using standard procedures. The coordinates of each sampling location were established using Global Navigation Satellite System (GNSS) RTK Receivers at the site and an interpolation technique was used to analyze the spatial patterns of drinking water quality parameters in the case study area. The Weighted Arithmetic Water Quality Index method was used to find the suitability of water for drinking purposes. The test results revealed that turbidity, colour, TDS, total hardness, total alkalinity, Chloride, Fluoride, Total Iron, Calcium, and Sulphate concentrations exceeded the Sri Lankan drinking water quality standards values. Further, pH, nitrate, nitrite, and total phosphates are within the Sri Lankan Standards for all 120 wells. Heavy metals such as Arsenic and cadmium were not detected in any of the samples but lead contamination was detected in six samples. The microbiological results indicate that the entire study area was contaminated with total coliform and E.coli bacteria. According to the physical and chemical parameters, the WQI value varies from 4.5 to 287.2 and 72 wells are suitable for drinking purposes. When microbiological parameters were incorporated, a mere 3 wells were deemed suitable for drinking purposes. Therefore, it is highly recommended to conduct regular chlorination or disinfection of the wells. Sun, 01 Jan 2023 00:00:00 GMT http://drw.jfn.ac.lk/handle/123456789/430 2023-01-01T00:00:00Z http://drw.jfn.ac.lk/handle/123456789/428 Assessment of water quality and pollution in Gurunagar fishery harbour, Jaffna, Sri Lanka Sivanandan, A.; Kuganathan, S.; Ketheesan, B. Coastal marine water pollution is caused by anthropogenic activities either directly or indirectly. Substances released into marine coastal environment result in deleterious effects such as harmful to living resources, hazards to human health, hindrance to marine activities including fishing. As such, Gurunagar harbour is often polluted by several waste effluents generated within the region. Research was conducted with the objective to determine the quality of water in the fish landing site at Gurunagar and type of wastes discharged into the main water stream. Investigations were carried out for six months period from January to June 2020. Three potential sampling locations were selected along three main drainages where amalgamation takes place at the coastal region. Samples were collected from 10 m, 30 m and 60 m at the interior portion of the harbour whereas control unit was kept at 500 m at the exterior portion of harbour. Fifteen water quality parameters were analyzed to find out the level of contamination in the water. Results showed that physical parameters such as temperature, salinity, total suspended solids, colour and turbidity were kept under the tolerance level. Chemical parameters such as BOD, COD, Nitrate, and Phosphate were accounted above the limit as 139.00 ± 29.57 mg/l, 306.70 ± 70.5 mg/l, 78.70 ± 8.03 mg/l, and 1.42 ±0.2448 mg/l, respectively. There was no significant difference between three main drainage channels considered. Hazardous wastes of oil and grease accumulated as 14.333 ± 2.345mg/l in the harbour water and, the Noxious heavy metals namely Hg and Pb were estimated as 0.03544 ± 0.02845 mg/l and 1.97 ± 0.1815 mg/l, respectively; and these concentrations are crucially above the tolerance limits. The Hg concentration in Jaffna Teaching Hospital drainage was reported as 0.0315 ±0.02247 which is inevitably higher than the threshold level. It was found parameter variables along with the sampling distances and significantly high value was obtained at the distance of 10 m from the coast. The present study recommends that initiatives should be made by the government officials to adopt an effective waste disposal and management system among the coastal communities, in the future. Sun, 01 Jan 2023 00:00:00 GMT http://drw.jfn.ac.lk/handle/123456789/428 2023-01-01T00:00:00Z http://drw.jfn.ac.lk/handle/123456789/425 Assessing and mapping the groundwater potability in Vallipuram coastal area, Jaffna peninsula, Sri Lanka by weighted arithmetic water quality indexing method. Anoja, N.; Sharmilaa, R.; Sirisena, K. A. Ground water is an extremely valuable resource and pollution of ground water resources is a matter of serious concern. Though more than 80% of people in the Jaffna region, rely on ground water self-supply wells, the extent to which self-supply wells delivers safe water and the associated risk factors for contamination remain unclear. In response to community requests and the National Water Supply & Drainage Board's (NWS&DB) provision of water from four ground water wells through 150m lateral pipes, a study was initiated to assess quality of well water within a 1.5km radius from the NWS&DB wells. This study involved the evaluation and mapping of groundwater quality parameters and the application of the Water Quality Index (WQI) to determine water potability. The study revealed that numerous parameters, such as turbidity, color, TDS, total hardness, total alkalinity, chloride, fluoride, total iron, calcium, and sulfate concentrations, exceeded SriLankan drinking water standards, while pH, nitrate, nitrite, and total phosphates remained within acceptable limits in all 120 wells. Heavy metals like arsenic and cadmium were absent in all samples. Microbiological results showed contamination with total coliformand E.coli bacteria throughout the study area. Considering physical and chemical parameters, the WQI values ranged from 4.5 to 287.2, with 72 wells suitable for drinking. However, when microbiological parameters were factored in, only three wells were deemed safe for drinking, underscoring the critical necessity for aquifer protection, thorough cleaning, and the immediate implementation of regular well chlorination or disinfection measures tosafeguard the health and well-being of the community. Sun, 01 Jan 2023 00:00:00 GMT http://drw.jfn.ac.lk/handle/123456789/425 2023-01-01T00:00:00Z http://drw.jfn.ac.lk/handle/123456789/424 Challenges Ahead in Groundwater of Sri Lanka Asanthi, H.B. Groundwater has been a safe water storage in Sri Lanka throughout history and the unique characteristics of different aquifers impact variation of the water quality. However, due to population growth, unplanned urbanization, intensive agriculture, improper waste management, etc., the groundwater quality is considered unsafe. Therefore, it is important to refer to the available data related to the groundwater quality of Sri Lanka. Saltwater intrusion is a considerable factor in shallow karstic aquifers and as a result, relatively higher electrical conductivity, water hardness, total alkalinity, and higher anions concentrations (chloride, sulfate) were observed in the Jaffna area. The dry zone including Padaviya and Hambanthota shows relatively higher water hardness and fluoride in groundwater. Nitrate concentration is also a considerable factor, especially in the Jaffna and Padaviya areas may be due to intensive agriculture. Identification of groundwater recharge zones, recharge estimates, continuous monitoring of groundwater quality, vulnerability mapping of aquifers, and proper planning of urbanization have been identified as challenges ahead in groundwater of Sri Lanka and it is essential to include those items in the National Water Policy in Sri Lanka. Sun, 01 Jan 2023 00:00:00 GMT http://drw.jfn.ac.lk/handle/123456789/424 2023-01-01T00:00:00Z