A NOXIOUS weed outbreak capable of completely choking freshwater streams and rivers has been discovered in the wetlands of Connection Creek and the Maria River.
Salvinia molesta – a NSW declared Class 3 Noxious Weed – moved throughout the wetlands and into the systems after the recent bouts of severe flooding.
It was previously contained and monitored in a reserve between Point Plomer and Crescent Head.
To prevent the further bloom of the aggressive aquatic weed the Port Macquarie-Hastings Council, Kempsey Shire Council and the Roads and Maritimes Services are implementing an integrated approach to tackling the problem.
Director of development and environment Matt Rogers said early intervention was key when it came to containing the bloom.
“With these sorts of weeds it is very important you get in on the front foot early if you want to have any chance of keeping it under control,” Mr Rogers said.
Three floating booms will be placed across Connection Creek, some 1.5 kilometres upstream from the junction with the Maria River, to block the movement of salvinia.
“This will allow the targeted treatment of the infestation by containing it within a limited stretch of the stream where it can be accessed by weed control operators using a combination of physical removal, herbicide application and biological control measures,” Mr Rogers said.
The RMS’s forced closure of a section of the creek will prevent boat access until the outbreak is controlled, but determining a specific timeframe would be difficult at this stage of the project.
Mr Rogers said blocking boat access would prevent the accidental spread of salvinia through fishing gear, propellers, boats and other equipment.
Other natural propellants such as birds, ducks, tides and wind will be unpreventable and the high mobility of the weed would make strict control measures paramount during early stages of prevention.
In a worst case scenario favourable conditions could cause the salvinia to completely cover the surface of a creek in the space of just a few months, Mr Rogers said.
This would be of major detriment to the natural ecosystem and native fish populations throughout the Maria River system.
“It is an extremely aggressive weed that can multiply in a matter of days and weeks,” Mr Rogers said.
“There’ll be a long road ahead of us in terms of constant monitoring and inspections.”
Land owners are urged to assist council in the management of this outbreak.
If you are unsure of a particular weed on your property you can contact council for more information.
Council asks locals to assist by remaining out of the closed areas, by advising their local council of any damage to the booms and of any new salvinia infestations.
Land owners are ultimately responsible for any weed infestations on their own property.
Weed control operators will be carrying out regular inspection and control works over the next one to two years to remove the salvinia from affected areas.