Sampling Sites
| Name of water | Number of sites |
| Daff y Nant brook | 1 |
| Dore | 10 |
| Dulas | 2 |
| Ennig | 2 |
| Felindre Brook | 1 |
| Gamber | 3 |
| Garren | 6 |
| Ithon | 1 |
| Llanerch Brook | 1 |
| Llynfi | 2 |
| Lugg | 4 |
| Luke Brook | 1 |
| Monnow | 1 |
| Olchen Brook | 1 |
| Pentaloe Brook | 2 |
| Pont y Weston Brook | 4 |
| West Brook | 1 |
| Worm | 7 |
| Wye | 13 |