Formula

Reference

Total Hardness

TH (CaCO₃) mg/L = 2.5 Ca²⁺ + 4.1 Mg²⁺

[1]

Water Quality Index

$WQI={\displaystyle \sum _{i=1}^n{W}_i{q}_i}{\left[{\displaystyle \sum _{i=1}^n{W}_i}\right]}^{-1}$

[20]

CAI₁

[Cl − (Na + K)]/Cl]

[14] [15] [16]

CAI₂

[Cl − (Na + K)]/SO₄ + HCO₃ + CO₃ + NO₃]

[14] [15] [16]