Water Quality Index Calculator

Calculate a simplified water quality index (WQI) from dissolved oxygen, pH, turbidity, and temperature parameters.

0-100
0-100
0-100
0-100
0-100

Water Quality Index

74.3 WQI

DO Contribution22.5 points
Turbidity Contribution14.0 points
Nutrient Contribution13.0 points

Water Quality Index vs Dissolved Oxygen Score

How to Calculate Water Quality Index

The WQI combines multiple water quality parameters into a single score.

Formula

WQI = DO(0.30) + pH(0.15) + Turbidity(0.20) + Temp(0.15) + Nutrients(0.20)

Rating Scale

  • 90-100: Excellent
  • 70-89: Good
  • 50-69: Medium
  • 25-49: Bad
  • 0-24: Very Bad
  • Each parameter is first converted to a 0-100 sub-index score based on its measured value.

    Example Calculation

    A water body with DO=75, pH=80, Turbidity=70, Temperature=85, Nutrients=65.

    1. 01DO: 75 * 0.30 = 22.5
    2. 02pH: 80 * 0.15 = 12.0
    3. 03Turbidity: 70 * 0.20 = 14.0
    4. 04Temperature: 85 * 0.15 = 12.75
    5. 05Nutrients: 65 * 0.20 = 13.0
    6. 06WQI = 22.5 + 12.0 + 14.0 + 12.75 + 13.0 = 74.3 (Good)

    Frequently Asked Questions

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