Water Quality Index Calculator for Surface Water
The Water Quality Index is a 100-point scale that summarizes results from a total of nine different measurements when complete.
A teacher using the Water Quality Index for Surface
Waters as an educational tool in the classroom.
Using the book, Field Manual for Water Quality Monitoring, the National Sanitation Foundation surveyed 142 people, representing a wide range of positions at the local, state, and national level, about 35 water quality tests for possible inclusion in an index. Nine factors were chosen and some were judged more important than others, so a weighted mean is used to combine the values.
So that field measurements could be converted to index values, respondents were asked by questionnaire to graph the level of water quality (0 through 100) corresponding to the field measurements (e.g., pH 2-12). The curves were then averaged and are thought to represent the best professional judgment at this time.
The Water Quality Index Calculator below allows you to enter the latitude and longitude for your site or to pick your location from the Google Earth Map. The calculator completes the individual and group calculation and permits you to generate a customized report.
Two Modes - Actual and Training
The Water Quality Index Calculator has two modes - Actual and Training. Actual is meant for real-world testing of actual sites; Training mode is used for educational simulations. If you choose actual, your data will be contributed to our Citizen Science Global Water Quality Database & Map that we will be making available as a shared public resource.
Click here to learn more about how to collect sample data for the nine surface water quality index calculator input values. Ensure sample values are in the correct measurement system for each input value below. This calculator utilizes nine input values chosen as the most important factors when determining the quality of an outdoor water source from Field Manual for Water Quality Monitoring. You will have an opportunity to download calculated results after the submission as a PDF file.
For users that are part of an Educational Outreach / Conservation Program or those who are actively sampling and testing in order to provide actual data to this effort - please register to join the Global Directory of Citizen Scientist Teams, Conservation Groups, and Watershed Organizations.
Notes: mg/L approx. equal to ppm
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