Heavy icebreakers, which can move through 21-foot thick-ridged ice sheets at 3 knots, are needed to provide safe winter passage through the Arctic, a task that falls entirely to the Coast Guard as the only U.S. government agency with an ice breaking mission. The problem is shared by all Arctic nations, with the exception of Russia, which has a half-dozen heavy icebreakers in its fleet of more than 40 ice-capable vessels – and is the only nation with any recent experience in building such ships.

“Our small ATON fleet of river tenders, inland buoy tenders, and construction tenders work on federal inland waterways and western rivers throughout the country, working hard to keep the flow of traffic on rivers going … But as they get older they become more expensive to maintain, even as they keep meeting our mission requirements. We have talked about replacing them in the future, but there are no current plans. …

Winter ice breaking also is important to the maritime safety mission on the Great Lakes, northern New England’s coastal areas, and navigable inland waterways, and the Antarctic. While the Coast Guard’s leadership role in the International Ice Patrol was established after the RMS Titanic struck an iceberg and sank in the North Atlantic in 1912, that task is limited to charting the movement of icebergs, establishing safe passage routes for ships and, on those rare occasions when a ship becomes disabled there, crew and passenger rescue operations.

“We have a system for ATON in waters that are or may be ice covered, replacing standard buoys with a specifically designed ice buoy. That’s a major part of the mission in districts 1 [Boston, Massachusetts] and 9 [Cleveland, Ohio] because they have to replace the regular buoys every fall, then reverse that process in the spring,” Lt. Cmdr. Margaret Kennedy, chief of the Aids to Navigation and Icebreaker Division, told Coast Guard Outlook.

Maritime safety outside the Arctic has been enhanced by the Coast Guard’s in-service vessel sustainment effort for Juniper-class seagoing buoy tenders and Bay-class ice breaking tugs. The former began a mid-life maintenance (MLM) program in July with the CGC Oak, while the service life extension (SLE) upgrade on the first of the latter has been completed and two more are now in the Baltimore shipyard.

The seagoing buoy tenders are multi-mission cutters involved in many of the 11 Coast Guard missions. They are classified as ice-capable rather than icebreakers, able to break through 14 inches of fresh-water ice at 3 knots or 36 inches with a backing and ramming method. Their primary mission is ATON servicing, but those stationed in districts 9 and 1 also do winter ice-breaking on the Great Lakes and northeast coast.

“The plan is for all 16 of those to be completed by 2025. We commissioned the first – the Juniper – in 1996 and the newest – the Alder – in 2004, so they will reach the end of their planned service life by the time the mid-life program is over. But they will continue to operate as long as they are useful, which will be determined by future engineering evaluations,” Kennedy said.

“That is not a service life extension but a mid-life maintenance effort built into the service life to ensure they make their maximum 30 years in service. We are doing some tech upgrades – some haven’t been looked at since they were built – upgrades to the propulsion control system, the machinery plant control system, preservation of underbody hull coatings and weight handling on the buoy and smallboats deck.”

The primary mission of the Bay class is ice-breaking, ice escort, and maintenance; two are equipped with a barge, from which they do ATON servicing. The SLE is intended to add an additional 10 to 15 years to the service lives of the nine tugs. The last Bay class will reach the end of that extension by 2033.

“The SLE doesn’t add any additional capabilities, but does assure they are able to continue operating past the end of their 30-year design service life,” she explained. “So they are getting an upgraded firefighting system, the bubbler system that creates air bubbles underwater to push ice away from the hull, some habitability upgrades for the crew, some exterior work on underbody and superstructure coatings and an overhaul of the main motor.

“Ensuring the flow of commerce through the winter months is our goal and we’ve kept doing that. What we’re doing with the Bay-class SLE and Juniper[-class]MLM means we will have the capabilities we need to make sure the transportation system keeps working smoothly.”

That also applies to the nation’s navigable inland waterways, which are maintained by some of the oldest vessels in the Coast Guard fleet.