Parameters | Dimension | Weight | Function |
Dissolved oxygen | % saturation | 0.109 | 0.82 DO + 10.56 |
BOD5 | mg/L, at 20˚C | 0.097 | 108 (BOD)−0.3494 |
Coliform | NMP-Coli/100 ml | 0.090 | 136 (COLI)−0.1311 |
E. coli | Faecal-Coli/100 ml | 0.116 | 106 (E-COLI)−0.1286 |
Alkalinity | ppm CaCO3 | 0.063 | 110 (ALK)−0.1342 |
Hardness | ppm CaCO3 | 0.065 | 552 (HA)−0.4488 |
Chloride | Mg/L, fresh water | 0.074 | 391 (CL)−3480 |
Sp. Conductance | µmhos/cm 25˚C | 0.079 | 506 (SPC)−0.3315 |
pH | pH < 6.9 pH-units (6.9 - 7.1) pH > 7.1 | 0.077 | 100.6803 + 0.1856 (pH) 1 103.65 − 0.2216 (pH) |
Nitrate | As NO3, mg/L | 0.090 | 125 (N)−0.2718 |
Temperature | ˚C | 0.077 |
|
Colour | Colour units-Pt std | 0.063 | 127 (C)0.2394 |