Long term solution for Shotover Wastewater Treatment Plant

Work is already underway to construct and commission a new, additional Modified Ludzack-Ettinger (MLE) reactor train which is due to be completed before the end of 2025.  This will result in further significant improvements to the quality of the treated water discharged from the facility by enabling the removal of oxidation ponds from the treatment process. Currently 20% of the raw wastewater continues to be treated within the pond system, which we are progressively decommissioning.

Following the decommissioning of the remaining oxidation ponds, an additional ‘calamity pond’  will be constructed by the end of 2027 in the southern area of Pond 3. This will enable treated water to be diverted away from the disposal solution and temporarily stored in the unlikely event the quality of the treated water is compromised. If that ever was the case, the stored water will then be able to be pumped back for re-processing through the facility.

In response to the current challenges with the existing disposal field, QLDC has allocated $77.5M through the current Long Term Plan to implement a new disposal strategy for the Shotover WWTP.  This project commenced in October 2024 and a new disposal solution is expected to be in operation by the end of 2030.  

More information on the new disposal strategy will be shared with the community once options have been assessed and a preferred solution identified.