The rāhui placed on Wellington harbour after possibly millions of litres of sewage poured into it has been lifted although some parts remain off-limits.

Photo: RNZ / Rob Dixon

The rāhui from Ngauranga to Point Halswell, put on by Taranaki Whānui, had forbidden swimming, fishing and the collection of shellfish. Public health warning signs were also erected near the shorelines.

Waste began spilling into the harbour on December 20 after a pipeline collapsed, blocking sewage from being able to flow to the treatment plant.

Wellington Water acting chief executive Jeremy McKibbin confirmed people could now swim in Oriental Bay and paddle and canoe in the inner harbour.

However the Whairapo Lagoon entrance through the dive platform to the Overseas Passenger Terminal will remain off-limits because of a separate sewage issue.

McKibbin said cooperation between contractors, engineers, council and other agency staff was critical in getting the overground pipe completed by Christmas eve.

"It's thanks to their hard work in the lead up to Christmas, and since then, that we've been able to get to this point so quickly. We're very grateful for the support that they and the community have shown us."

Work on a permanent, underground pipe will start in January 2020 and is expected to be finished by the end of February.

Until then businesses around will have to live with a sewage pipe, which is 600mm in diameter, running over ground.