Heavy rain raises risk of untreated wastewater reaching Wellington south coast

Sunday, 15 February 2026

The incident has been labelled 'devastating' by experts.

Steady progress is being made to clean and inspect damage at the Moa Point Wastewater Treatment Plant, but worsening weather is raising concerns about further contamination along Wellington’s south coast.

The plant is continuing to discharge screened wastewater through the long outfall pipe. This removes solid items such as wipes and sanitary products, but the wastewater has not undergone biological or ultraviolet treatment.

No wastewater has been discharged through the short outfall pipe since 9pm on February 5. However, with heavy rain and high swells forecast, officials anticipate some unscreened wastewater may need to be discharged through the shorter pipe, which releases water closer to shore.

The focus, according to Wellington Water, is to minimise any use of the short outfall while keeping operators safe.

Residents are urged not to flush non-biodegradable items such as wipes and sanitary products to help reduce the amount of solid material entering the system.

Untreated wastewater poses a high risk to public health, and the community is strongly advised to stay away from south coast beaches.

This latest update comes just hours after Wellington Water chairman Nick Leggett resigned from the role citing the failure at Moa Point, and admitting that leadership must accept responsibility for the “deeply serious” event.

Officials monitor Moa Point plant as strong winds, swells and rainfall increase contamination concerns (file pic).

Water sampling carried out on February 13 by Regional Public Health and Greater Wellington Regional Council shows elevated levels of Enterococcus bacteria, as expected in wet conditions.

Heavy rainfall affects water quality across Wellington, and public health officials advise people not to swim for two days following rain.

Strong southerly winds combined with rainfall may increase the likelihood of untreated wastewater being pushed towards the shoreline. Testing takes at least 24 hours, and results can vary significantly depending on conditions.

Officials say odour levels are unlikely today due to forecast strong winds. Shoreline inspections and debris clean-up will resume once the weather improves.

The situation remains complex and changeable, with daily water sampling to continue until further notice.