Proposed icebreakers of Canada

In the past years, a number of icebreakers have been proposed but not yet built in Canada.

Polar 8
In 1985 the Government of Canada announced plans to build a fleet of several icebreakers for the Canadian Coast Guard. This was known as the Polar 8 Project and would have consisted of massive icebreakers. The Polar 8 project was cancelled in 1990 while still in the design stage." in favour of refitting the CCGS Louis S. St-Laurent.

The original $700 million per vessel pricetag of an icebreaker from the Polar 8 Project in 1985, when adjusted for inflation to 2008, would be approximately $1.3 billion, therefore it is quite likely that the CCGS John G. Diefenbaker will be a much smaller vessel than the Polar 8 Project envisioned, albeit larger than the CCGS Louis S. St-Laurent.

Arctic Patrol Ship Project
The federal government announced in 2007 that it would procure a fleet of six to eight light icebreaker patrol ships for the Canadian Forces. The Arctic Patrol Ship Project is based on a Royal Norwegian Navy patrol boat design (see NoCGV Svalbard) used in the Barents Sea with a polar class of PC 5; thus they will be significantly smaller and less capable than what was envisioned in the Polar 8 project, which would have extended the capabilities of the Canadian Coast Guard's operations in the Arctic Ocean. Some media and political sources termed these vessels with their limited ice capability to be mere "slush breakers." The Arctic Offshore Patrol Ship Project has been designed by STX Canada Marine, based in Vancouver, BC. The design will be the first ships to be built under the combat ships package awarded to Irving Shipbuilding in the October 19, 2011 announcement of the National Shipbuilding Procurement Strategy. A contract for construction of these ships is currently being negotiated for signing in early 2012 and delivery of the first vessel in 2014.