Wellingtonians are being warned to stay out of the water after raw sewage was discharged into the ocean.

An “equipment failure” at the Moa Point Wastewater Treatment Plant early this morning led to the site being evacuated after multiple floors were inundated with untreated wastewater, Wellington Water said.

The capital’s water provider has apologised for the “unacceptable” situation, which is causing raw sewage flood into local beaches.

“Our immediate focus is restoring power to the plant, resuming service, and diverting wastewater,” chief executive Pat Dougherty said.

“Wellington Water has set up an emergency management team and [is] working at pace to stabilise the situation.”

The facility, near the city’s airport, is expected to be closed for “an extended period”, the organisation said.

In a post on social media, Wellington City Council said that “due to high rainfall, there has been a discharge of partially treated wastewater from the Western Wastewater Treatment Plant into the Karori Stream, which flows into the sea on the South Coast.”

“At the Moa Point Wastewater Treatment Plant a mechanical failure has resulted in discharge of partially treated wastewater that will emerge around 1.8km off the coast of Lyall Bay and untreated at Tarakena Bay. Wellington Water are investigating.”

The discharge may cause the water to appear cloudy or murky, the council said.

There was an issue at the Moa Point treatment plant, council said.

“For your health and safety, please stay out of the water and check LAWA.”

LAWA (Land Air Water Aotearoa) is a website that offers environmental data.

The council called it a “major incident” and said they were urging people to avoid beaches on the South Coast and around the harbour.

“Raw, untreated sewage is flowing into the sea from the old ‘short’ outfall pipe,” they said in another post.

Wellington Water said it will have “boots on the ground today, with our customer teams distributing information about public health and advice.”

“An environmental team will be undertaking water quality testing. More information will be provided at lunchtime today. This is a complex incident, and all necessary resources are being utilised,” the capital’s water provider said.