Newly released Moa Point report reveals ignored design flaws and risk assessments before February flood

A newly released Aecom study, commissioned by Wellington Water and disclosed after a local-government information request, outlines a series of design and procedural failures that led to the Moa Point wastewater plant flood in February 2026. The report points to critical flaws such as underground electrical equipment, missing water-level alarms, and air-relief valves that were too small and could jam. It also notes that hydraulic and air-handling capacities were never reassessed during UV channel upgrades, despite identified risks.

Five earlier inundation incidents and recommended flow-limiting measures were ignored, and a communications breakdown delayed operator response until after emergency services had arrived. Veolia, the plant’s operator, argues the report is not independent and emphasizes that it was not responsible for the upgrade decisions. Tiaki Wai chief executive Michael Brewster said the findings are being used to improve regional wastewater resilience.