
Canadian Coast Guard Multi-Purpose Icebreaker (MPI). Source: Seaspan
Note: The MPI image does not show the right propulsors; it will use Steerprop’s contra-rotating propulsors (CRP). Additionally according to Seaspan, the design could easily be upgraded to PC3. Confirmation from Seaspan and Aker Arctic.
Sixty Degrees North provides an excellent overview of what happened in the Great Lakes and St Lawrence Seaway including both the US and Canadian Coast Guards.
There is a particularly interesting paragraph,
“As I reported in the December U.S. Coast Guard Roundup, the U.S. Coast Guard is looking to expand its domestic (i.e. Great Lakes) icebreaking fleet by adding 18 new icebreaker— ten Homeland Security Cutter-Mediums (HSC-Ms) to replace the Bay-class, and seven Homeland Security Cutter-Light (HSC-Ls) to replace its aging 65-foot light icebreaking tugs (WYTLs) and 49-foot buoy utility stern loading boats (BUSLs). There is also a U.S. Coast Guard web page for a Homeland Security Cutter-Heavy (HSC-H), a vessel designed to augment the Great Lakes heavy icebreaker Mackinaw , although there is (as of today) no official Request for Information (RFI).”
The author also speculates,
Interestingly, the Canadian Coast Guard plans on replacing its older light icebreakers with the Multi-Purpose Icebreaker (previously called the Multi-Purpose Vessel). According to the Canada’s National Shipbuilding Strategy, the missions of the MPIs include:
- icebreaking in the Arctic in moderate ice conditions
- assisting with shipping and springtime flood control in the St. Lawrence waterway and Great Lakes regions
- conducting missions involving search and rescue, emergency response, and security and protection
- maintaining Canada’s marine navigation system, composed of approximately 17,000 aids to navigation
The U.S. Coast Guard is acquiring six Arctic Security Cutters that use the MPI design. It will be interesting to see if any of those vessels end up operating in the Great Lakes. (emphasis applied–Chuck)
These ships (pictured above) are larger and more powerful than USCGC Mackinaw, but are small enough to transit the St Lawrence lock system. Like many Canadian icebreakers, they also include a buoy tending capability.









