Replacement Cook Strait ferry Stena Alegra will be out of service for five days after it was damaged berthing yesterday.
The ferry is tied up at Wellington wharf, with a gash about six metres long visible in its hull above the waterline.
Workers were this afternoon seen repairing the gash.
The accident happened about 1pm yesterday as the chartered ferry was berthing after a voyage from Picton.
All passengers and cargo were taken off before the ship was moved to nearby Aotea Quay for a detailed damage assessment.
An Interislander spokeswoman said the accident, which happened while the ship was berthing at Wellington, happened in "the midst of extreme weather conditions".
Repairs would take four to five days and all Stena Alegra sailings until Sunday had been cancelled, she said.
All other ferries were running to schedule, despite the Interislander website showing all but one sailing today were suspended.
The spokeswoman said that while bookings were suspended, sailings were not.
The Stena Alegra has been on the Cook Strait run since February, as the replacement for the Aratere, which is still in dry dock in Singapore after losing a propeller in Cook Strait in November.
Interislander general manager Thomas Davis this week confirmed cracks had been found in both of the Aratere's rudders.
Aratere was on the verge of being returned to the water for sea trials this week with two new propeller shafts and refurbished stabilisers, after one propeller shaft snapped in Cook Strait on a routine sailing from Picton to Wellington on November 5.
Davis said Aratere's rudder problem was discovered when Aratere's two rudders were being refitted to the ship.
Commenting on Aratere's rudder problem on Monday, Davis said Stena Alegra would continue on the Cook Strait run as the replacement charter ship for Aratere.
- The Dominion Post