| Index | Quality | WQI-wet | % | WQI-dry | % |
| 0 - 25 | Excellent | 10 | 50 | 1 | 5 |
| 26 - 50 | Good | 6 | 30 | 3 | 15 |
| 51 - 75 | Poor | 4 | 20 | 2 | 10 |
| 76 - 100 | Very poor | 0 | 0 | 0 | 0 |
| >100 | Unsuitable | 0 | 0 | 14 | 70 |