NEW YORK — The crew of the Coast Guard Cutter Thunder Bay, a 140-foot ice-breaking tug home-ported in Rockland, is on the Hudson River this week, breaking ice between Kingston and Albany, to keep shipping channels open. Thunder Bay has a crew of more than 15 Coast Guard personnel, who have traveled southwest from Rockland to New York to help keep the Hudson River channels clear so vessels carrying primarily heating oil can move through the water.

"Today, overall, is a pretty good day,” said Lt. Zac Bender, commanding officer of the Thunder Bay, Feb. 5. “We've got a pretty good wind at about 20 knots and temperatures in the high 20s. We've definitely seen it colder and snowier throughout the week. We'll have to keep an eye on whether the low overnight temperatures created any refreezing, but overall I'd say it's a pretty good day to break ice."

An average of 300 vessels transit the river during the winter, carrying more than 10 million barrels of petroleum products to the Northeast communities, according to a news release from the Coast Guard.

The Coast Guard calls the mission “Operation Reliable Energy Northeast Winters (RENEW).”

“OP RENEW is the Coast Guard's region-wide effort to ensure Northeast communities have the security, supplies, and emergency resources they need throughout the winter,” the release said. “Of the heating oil used in the country, 75 percent of it is transported through New England, New York, and New Jersey, 90 percent of that is delivered by barges.”

Thunder Bay is one of nine 140-foot cutters that specialize in breaking up ice in rivers and bays on the East Coast and on the Great Lakes.

They were all built between 1979 and 1988, and according to Tugboat Enthusiasts of the Americas, they can break through ice up to 20 inches of thickness. They use a low-pressure-air hull lubrication ,or bubbler system, that forces air and water between the hull and ice, according to the Coast Guard.

“This system improves icebreaking capabilities by reducing resistance against the hull, reducing horsepower requirements,” the Coast Guard said.

The cutters are named after bays in the Northeast and Midwest, but to avoid confusion during radio transmissions, they are not home-ported near the bays for which they are named.

For example, the cutter Penobscot Bay is home-ported in Bayonne, New Jersey.

The 140-foot cutters are:

BISCAYNE BAY (WTGB 104) St. Ignace, MI

BRISTOL BAY* (WTGB 102) Detroit, MI

KATMAI BAY (WTGB 101) Sault Ste. Marie, MI

MOBILE BAY* (WTGB 103) Sturgeon Bay, WI

NEAH BAY (WTGB 105) Cleveland, OH

MORRO BAY (WTGB 106) Cleveland, OH

PENOBSCOT BAY (WTGB 107) Bayonne, NJ

STURGEON BAY (WTGB 109) Bayonne, NJ

THUNDER BAY (WTGB 108) Rockland, ME

Reach Editorial Director Lynda Clancy at lyndaclancy@penbaypilot.com; 207-706-6657