Abstract:
The Jaffna peninsula mainly depends on groundwater for drinking and other
purposes due to lack of fresh water resources. The objective of this study
was to evaluate the groundwater quality for its suitability for drinking
purpose. Water quality parameters such as total hardness, K+, NO3
- and
SO4
2- contents were determined for 32 wells, randomly selected in the
Jaffna municipal area, during December 2017 to March 2018. The water
quality parameters were analyzed based on Sri Lankan standards for potable
water–SLS 614:2013. The sulfate, fluoride and nitrate contents were
measured by using COD-Multiparameter-photometer. pH of the water
samples was measured by a portable pH meter. Flame photometer was
used to measure the potassium level. Measured nitrate content varied from
15-170.5 ppm, and this is about twelve-fold increase compared to previous
values of 30 years ago. Other water quality parameters pH, hardness, TDS,
sulfate and potassium varied as 6.5-8.5, 168-1232 , 189-5440, 5-700 and
1.2-144 ppm, respectively. It is evident from the results that 94% of wells
has higher hardness and TDS compared to Sri Lankan standard. 28% of
wells and 31% of wells showed higher nitrate and sulfate contents,
respectively. Higher potassium content was found in 85% of wells.
Because of the inadequate sewage disposal facilities, highly polluted areas
near the wells and most of the wells are situated close to soakage pits of the
toilets, the water quality is not suitable for drinking purpose in Jaffna
municipal area. The excessive ions from the water should be removed
before the water is consumed for drinking.
