A Canadian navy submarine that has undergone nearly three quarters of a billion dollars in repairs and upgrades after running aground off British Columbia in 2011 has returned to active service for the first time since the accident.
The Royal Canadian Navy, in a social media post on Wednesday, described HMCS Corner Brook as “now the most advanced submarine in the Canadian fleet,” adding the vessel “will play a key role in supporting a free and open Indo-Pacific region.”
The submarine returned to the waters off Victoria for sea trials in February, nearly 14 years since it struck bottom near Nootka Sound on the west coast of Vancouver Island.
The collision tore a hole in the submarine’s hull and triggered a cascade of system failures requiring repairs, refits and further delays in drydock.
Repairs, upgrades total $715M
Those repairs included $20 million worth of work to fix the immediate damage sustained in the grounding incident, plus an additional $695 million in further repairs and upgrades as part of the sub’s maintenance cycle, according to a National Defence spokesperson.
HMCS Corner Brook is one of four hunter-killer subs Canada bought second-hand from Britain in 1998. The initial $750-million price tag for the vessels is a fraction of the billions of dollars the federal government has since poured into maintaining them.
Read more: Canadian submarine returns to sea 14 years after collision
The repairs and upgrades undertaken on HMCS Corner Brook since it struck the ocean floor in 2011 include structural fixes to its bow and corrosion repairs on the external pressure hull and ballast tanks, Kened Sadiku, a spokesperson for National Defence, said in an emailed statement to CTV News in February.
The vessel has also undergone an estimated 56 engineering changes to replace obsolete systems and improve its operating capabilities, Sadiku said, including the installation of a new mast – an upgrade that is planned for all four of Canada’s subs.
The new mast, manufactured by L3Harris, was acquired from the United States under its foreign military sales program, and is similar to those on the U.S. navy’s Virginia-class submarines, according to National Defence.
New cooling and refrigeration systems were also installed on HMCS Corner Brook “to comply with modern environmental standards and support modern weapon systems,” Sadiku said.
🟢 #HMCSCornerBrook is back online and ready to return to operations. Freshly upgraded, it's now the most advanced submarine in the Canadian fleet, and will play a key role in supporting a free and open Indo-Pacific region.#HelpLeadFight@CanadianForces pic.twitter.com/OZNkrXx3h7
— Royal Canadian Navy (@RoyalCanNavy) April 2, 2025
At no point over the past decade have more than two of Canada’s four submarines been operational at any one time. The navy attempted to hit that milestone in 2020, and tried again in 2021, but the service’s ambitions for the sub fleet largely hinged on the health of HMCS Corner Brook.
In August 2019, while the submarine was docked for repairs near Victoria, a damaging fire broke out on board. Then in March 2021, the sub’s main ballast tank ruptured during testing by contractor Babcock Canada, extending the sub’s already lengthy dry-dock period and putting further tests on hold.
Last September, the federal government formally launched its plan to acquire up to 12 new submarines to replace the existing fleet, which is expected to be decommissioned in the mid to late 2030s.
