Repairs to the last of Canada's Second World War corvettes will be extended into next year after crews uncovered more hull deterioration on the HMCS Sackville than they'd hoped to find.

That means the popular Halifax waterfront tourist attraction likely won't be returned to her berth near the Maritime Museum of the Atlantic until 2019.

"We knew that we were dealing with a lot of unknowns," said Cdr. Ret'd Wendall Brown, who chairs the board of the Canadian Naval Memorial Trust. "It was cautious optimism to have it back in the water this season."

Cdr Ret'd Wendall Brown chairs the board of the Canadian Naval Memorial Trust, the guardian of HMCS Sackville. (Elizabeth Chiu/CBC)

In January, the federal government earmarked $3.5 million to refit the ship, which was designated Canada's Naval Memorial in 1985.

HMCS Sackville last underwent repairs in 2008.

More 'tender loving care'

Brown said the team will secure the ship for the next five years by cladding the underwater hull with a sheet of steel. That will buy the trust time to fundraise money to permanently replace its steel skin — a solution that would extend the Sackville's life for another 50 years, he said.

The repair may include some cosmetic projects if there's time and money left before next summer.

"It does require some tender loving care to keep it seaworthy and secure it into the future," Brown said.

Meet its waterfront proxy: a movie prop

Having the ship out of the water this season means the trust will miss out on ticket sales. In 2017, about 25,000 people visited the Sackville at her berth.

To fill her shoes this year, Brown said they're bringing in a six-metre-long movie prop that will sit in a cradle on the waterfront.

"I think it was in the 90s, there was a movie made that involved the Sackville," Brown said. "To get some shots that were difficult to get with the ship itself, they constructed a 20-foot-long model.

"It's quite a realistic exterior representation of a corvette."

HMCS Sackville at its Halifax berth near the Maritime Museum of the Atlantic. (CBC)

The model has appeared as a parade float by the South Shore Naval Association. But it will mimic the full-size Sackville in more ways than one — restoration work on the model will also be underway on the Halifax waterfront docks.

Interpreters will still be available to answer questions about the Sackville for tourists, Brown said.