Water class | Alkalinity hazard | SAR values | % during dry season | % during wet season |
Excellent | S1 | <10 | 100 | 100 |
Good | S2 | 10 - 18 | - | - |
Doubtful | S3 | 18 - 26 | - | - |
Unsuitable | S4 | >26 | - | - |