Power and Water has completed desludging works at Pond 5 of the Palmerston Waste Stabilisation Ponds.
Desludging is a periodic maintenance process where treatment ponds are emptied, dried out and the sludge removed from the ponds to increase the efficiency and effectiveness of these facilities.
Residents in surrounding suburbs may have noticed an increase in odours during the desludging process over the past few months.
We attempt to mitigate this by implementing the management actions identified in our risk assessment for the activity. This includes:
- increasing oxygen levels in the ponds using reticulation and/or aeration
- stabilising removed sludge with natural chemicals to limit odour generation.
Once a pond is desludged, the risk of odour generated from a pond in normal operation is significantly reduced.
Some of the benefits of desludging include improving water discharge quality, allows ponds to operate at its original designed capacity and reduces odour through improved treatment processes.
Desludging takes several months and is carried out during the dry season. This allows us to drain the pond and allow it to dry naturally so sludge can be removed and stabilised on-site.
Upgrade works to the recirculation system is still underway. This process will help provide more oxygen into the primary ponds to mitigate odours and improve treatment processes.