Water Quality Index Calculator

Water Quality Index(WQI) is a scale which help to estimate an overall quality of water based on the values of water quality parameters.The biggest problem of WQI is, the quality of water varies with the source of water collection and the standard range of acceptability which varies between national and international bodies.The index used for estimation of water quality of drinking water can not give a correct estimation of water quality of industrial effluents.The drinking water standards is very high compare to the effluent coming from the industries.Again,a good water in India may not be good in USA as the prescribed standards of the two countries is different.

Generally water quality depends upon 20 odd parameters like BOD,DO,COD,TDS,TSS,Hardness,Heavy Metals,Colliforms etc.The range of acceptable values prescribed by different international and national bodies for these parameters defines the overall quality or acceptability of the water.The parameters which impacts the quality of water at a large scale, also varies with the source of water collection.

So when a WQI is developed such factors must be considered otherwise the index can be used only on similar kind of water.

WQI calculator given here is independent of the above problems and hence can be used for any type of water collected from any location.As you can change the range of usability and the priority of water parameters,the index is practically free of the constraints discussed above.

So to use the calculator,just collect the standard range of acceptability from the website of the national body of your country,prioritize the water parameters based on the source of the water.Assign high priority for the most influential parameter and least priority to unimportant ones.Then just click "Submit" get the WQI of the water samples.

The last row of the WQI column will give the WQI of the collected water based on the values of the parameter,standards and priority given by you.

Based on WQI,the following scale of acceptability, developed by NSF,USA , can be used to decide the overall quality of water :

* 90-100: Excellent

* 70-90: Good

* 50-70: Medium

* 25-50: Bad

* 0-25: Very Bad