| Date | Town | Level | Pesticide |
| 8/09/2011 | Nathalia RAW | Atrazine | 0.3 μg/L |
| 22/09/2011 | Nathalia | Atrazine | 0.1 μg/L |
| 22/09/2011 | Nathalia RAW | Atrazine | 0.1 μg/L |
| 22/09/2011 | Nathalia WTP | Atrazine | 0.1 μg/L |
| 4/10/2016 | Nathalia RAW | 2,4-dichlorophenoxyacetic acid | 0.1 μg/L |
| 4/10/2016 | Nathalia RAW | Atrazine | 0.1 μg/L |
