Published 21/09/2026
Moa Point wastewater report by AECOM now available
A report by consultant engineering firm AECOM into the failure of the Moa Point wastewater plant earlier this year has been published on the Tiaki Wai website.
The final report into the incident was commissioned by Wellington Water soon after the February 4 incident and was provided to Tiaki Wai on 13 August.
An initial delay in its availability to the public allowed time for discussions with insurers. Those conversations are now complete.
Tiaki Wai chief executive Mike Brewster said he was pleased it was now available and that the first principle of the organisation’s communications round Moa Point has always been transparency.
“It’s taken slightly longer to get this report out there because some insurance issues had to be worked through first, but we understand that people want as much information as they can get and we’ve been open in our commitment to make it available as soon as possible.
“There were concerns some content in the report could impact the insurance policy covering the plant, which had implications for Wellington ratepayers but that has been resolved.
“AECOM’s report is an important addition to our understanding of what happened on February 4, and it’s consistent with the findings of the Crown Review.
“The findings have directly informed our ongoing work to strengthen resilience across the region’s wastewater network, and as we’ve said we are well underway with the fix.”
The plant will start treating water again in November, with full operations expected by February 2027.
Known as the Moa Point Investigation Report, the AECOM report looks at the technical contributors to the plant failure, while the Crown Review looked at important contextual factors including oversight and management of contractual arrangements, setting of performance expectations, risk monitoring and incident response.
Notes for editors
The report is available here: tiakiwai.co.nz/moa-point-info-hub/reports
Parts of the AECOM report relating to personal information or commercially sensitive material have been redacted. Redactions are made on withholding grounds under the Local Government and Official Information and Meetings Act.
About Tiaki Wai
Tiaki Wai is the water services provider delivering safe, reliable, and sustainable drinking water, wastewater and stormwater services to around 155,000 homes and businesses across Wellington, Porirua, Lower Hutt and Upper Hutt.
We are responsible for over 6,800 km of pipelines, four drinking water treatment plants, four wastewater treatment plants, 140 drinking water storage reservoirs, and 354 pump stations across the region we serve.
Tiaki Wai took over from local councils on 1 July 2026 as the region-wide, publicly owned water services provider.
We are jointly owned by Wellington City Council, Porirua City Council, Hutt City Council, Upper Hutt City Council and Greater Wellington Regional Council as our shareholding councils, with mana whenua partners Ngāti Toa Rangatira and Taranaki Whānui ki Te Upoko o Te Ika.
We are governed by a Board of Directors and accountable to our community through the Tiaki Wai Partners Committee of representatives from our shareholding councils and Mana Whenua Partners.