Identification of Pollutant Concentration in Water Body using Remote Sensing Techniques

Remote sensing techniques are capable of enhancing the abilities of resource managers to monitor water bodies in a timely and cost-effective manner. Water can be used for several purposes. The water is pumped from various water bodies such as river, lake and reservoirs. Water is being polluted by direct discharge of effluents into the water bodies without proper treatment from industries. So, there is necessity for identification of the pollutants and their concentration in water. Remote sensors are capable to identify and quantify the composition of the materials in the water through their 'spectral signature'. The identification of pollutant type and their concentration in water is possible by spectral reflectance measured through spectroradiometer. There are several methods to determine the pollutants and their concentration by lab tests but it is tedious, so an innovative methodology by remote sensing techniques have proposed in this work.

The Noyyal river in Tamil Nadu have been selected as the study area for the current work. The reason is that the river is polluted by the dye industries in and around the Tirupur district. The type of pollutant and their concentration present in water have been determined using specroradiometer.

Three type of chemical salts calcium chloride, magnesium sulphate and sodium nitrate have been selected for this study. The spectral reflectance obtained for each salt in distilled water with various concentrations and also spectral curves were taken for water samples collected from Noyyal river. The different kind of salts identified by their absorption point 683nm,704nm and 690nm for calcium chloride, magnesium sulphate and sodium nitrate respectively. The type of pollutant in water samples from Noyyal river have identified through spectral curves of salts and mixtures of salts.