Shyni M, C. Unnikrishnan Warrier
Abstract: This study aims to investigate the groundwater quality for irrigation in the southern coastal area of Kannur district, Kerala. Fifty five samples were collected in premonsoon season (May 2016) and analysed for various physico chemical parameters such as pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), bicarbonate (HCO3-), chloride (Cl-) and sulphate (SO42-). From the hydrochemical analyses suitability of water for irrigation was evaluated based on Sodium Adsorption Ratio (SAR), Sodium Percent (Na %), Permeability Index (PI), Residual Sodium Carbonate (RSC), Kellys Ratio (KR), Magnesium Ratio (MR) and USSL diagram. Results of physico chemical analyses revealed majority of samples show an acidic pH with a mean value of 5.64, TDS of 85.33mg/l, EC of 157.63S/cm, Ca of 10.39mg/l, Mg of 3.05mg/l and Na of 12.16mg/l. SAR and RSC show that the groundwater of the study area is suitable for irrigation. USSL diagram showed that samples fall under C1S1 (low alkali and low salinity hazard), C2S1 (low alkali and medium salinity hazard) and C3S1 (low alkali and high salinity hazard) categories. Thus most of the groundwater samples are acceptable for irrigation purpose.
Keywords: Groundwater, Irrigation, Hydrochemistry, Kannur