The Petone Wharf in Lower Hutt has been closed down for urgent repair work, after an investigation found more than 20 of the piles keeping it up were in poor or very poor condition.
The wharf, built in 1908 and made of Australian hardwood timbers, was damaged as a result of two earthquakes in late December 2020.
An assessment of the construct found that the "several already deteriorated / weakened timber piles designed to support the Walkway Approach to the outer Petone Wharf failed in a catastrophic manner".
As a result, temporary repairs were undertaken and the wharf was re-opened to public use.
But with long-term repairs beginning this week, it was found keeping the wharf open would compromise public safety.
As common with damage in ageing structures, the report said, "there remains an extremely high risk of major loss if exposure to a further earthquake or storm event were to occur prior to sufficient remedial works being completed to secure and make safe the structure before such a potential event."
It deemed nine piles to be in a very poor condition, and a further 13 in a poor condition. It recommended all those piles to be repaired by remedial process immediately.
Repairs are expected to take six weeks, and the wharf will be closed throughout.