250 mL of Adyar Sewage river was taken.The odour of the sewge water was not good. 5 mL of sodium hypochlorite solution was added intially to the sewage water which changed the colur and on extra addition of 4 mL of sodium hypochlorite solution the colour of the solution became clear. After addition of sodium hypochlorite to the water as mentioned above the odour wasn't anymore unpleasant. Images post addition of sodium hypochlorite has been shown.