WATER QUALITY INDEX WITH MISSING PARAMETERS

Abstract

This paper presents the efficient modifications in calculating formula of water quality index. Water quality index provides us a single number which expresses overall water quality at a certain location and time which is based on several quality parameters. The objective of an index is to turn complex water quality data into information that is understandable and usable by the public. In this paper a formula will be found to calculate water quality index when the numerical value of some of it’s quality parameters are missing. The standard formula to calculate water quality index has nine water quality parameters- biochemical oxygen demand, dissolved oxygen, pH, nitrate, phosphate, faecal coliform, turbidity, total dissolve solids and temperature. Sometimes it becomes very difficult to find out the values of all these parameters because of lack of time or because of failure in testing. In that case the formula with missing parameters will help us to calculate water quality index.