It is defined as the presence of materials in the water which are harmful to the living beings when they cross their threshold concentration levels. It includes the heat, organic, inorganic and biological along with the radiological compounds. The surface water is not fit for drinking. It has organic, inorganic components along with the presence of bacteria, fungi, viruses, algae, protozoa’s and the other organisms. The water gets polluted when these organisms are present in the higher concentration. It makes the water unfit to drink. The degree of pollution depends upon the concentration of substances. There are some substances which can cause the pollution even at the low concentration. It includes the poisons, toxins, chemicals and few pathogens. The water pollution is not natural and is mainly man made. The natural water pollution consists of clay, animal wastes, minerals and leaves etc.