Moa Point Road to Recovery

On 20 May, we released the Recovery Road Map. The road map provides an indicative timeline and key milestones to restore the plant back to the way it was prior to the flooding, and address the design flaw identified in the hydraulic report.  We’ll report back on these key milestones regularly, so the community can hold us to account and keep track of our progress on the road to recovery. These dates are all indicative, and we’ll continue to do all we can to accelerate delivery.

You can view the road map here.

While all major repairs will be completed in November and full treatment processes will be up and running, minor repairs may take a few more months.  

When primary and secondary treatment are started up, the quality of wastewater being discharged out to Cook Strait will be gradually improved. Primary treatment will remove heavy particles like faecal matter and sand from the wastewater, and secondary treatment includes a biological process which breaks down waste, and ultraviolet disinfection. From this point, it may take 6 to 8 weeks for the bacteria to fully stabilise and UV disinfection to be fully effective. We will monitor the quality of this treated wastewater and provide this information to the community.

We’ve prioritised the work to get the core treatment functions of the plant up and running first, so we can get fully treated wastewater flowing through the long outfall pipe as soon as possible. The plant will be fully restored back to pre-4 February 2026 operations in February 2027. At this stage, we expect to have completed work on remediating the hydraulic issue in the bypass in late 2027. This issue was originally identified in the hydraulic report released in March. We may also be continuing work on previously planned aeration system renewal work at this time. 

The short outfall is only being used in heavy rain, when the flow of wastewater to the plant is greater than the amount that can safely be pumped up to the plant and out the long outfall. As of 20 May, this has happened on four occasions. The chance of the short outfall being used will progressively decrease as recovery continues and the pumping capacity to the plant is increased.

Outside of the use of the short outfall in heavy rain, all wastewater is being screened and pumped through the long outfall, which is 1.8km long. Discharging wastewater out the long outfall into Cook Strait allows for greater dilution, and large inorganic solids like wet wipes and tampons are screened out.

The short outfall is the designed overflow point for the inlet pump station to the plant. It was originally built as the main outfall discharge location from 1899 to 1998, and was retained to discharge wastewater in emergency situations like an extreme weather event or mechanical failure to prevent untreated wastewater discharging back up the network where it would pose a greater risk to the community and environment. There is no existing consent for use of the short outfall.

The plant and the long outfall were commissioned at the same time, sending fully treated wastewater out the long outfall pipe. Prior to the plant and long outfall being built, all wastewater was discharged through the short outfall into Tarakena Bay with milliscreening treatment only.