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[Graphic: Ship's seal]


WTGB 102/CGB 12001

The Mission

The Bristol Bay's mission in the Detroit River and surrounding waters varies according to the season. During the winter, she operates without the companion barge as an ice-breaking ship. With 2,500 horsepower and a strong reinforced bow, she can smash continuously through ice up to 18-20 inches thick, and can break through windrows from eight to twelve feet high! She also has special pumps for bubbling air under the ice, which help to break it up. As the shipping season now continues well into the winter, the Bristol Bay is kept busy maintaining an open navigation channel on the St. Clair and Detroit Rivers. She is also called upon to assist stranded freighters, stuck in the heavy ice that often piles up in the lower St. Clair River near Algonac and elsewhere.

Once the ice clears in the spring, the Bristol Bay begins the yearly job of installing and positioning 170 floating navigation aids in western Lake Erie, Lake St. Clair, and the Detroit River. For this task the tug is paired with her companion Aid-to-Naviation (ATON) barge to create a much larger working platform. Many buoys and their anchors can be stored on the barge deck, from which they can be hoisted over the side and carefully dropped into position. This is demanding work because these markers must be very accurately located. It requires extremely precise ship handling to manuever the anchors --which weight thousands of pounds-- to the exact location required. The bouys are also rather large, much bigger when on-deck than they appear from the water on a foggy day, and they must be attached to the anchors with just the right amount of chain to prevent them from wandering too far off station. Prior to the development of GPS and Differential-GPS, a corps of observers on the large bridge deck above the wheelhouse would coordinate the placement by concurrent observation of bearings on fixed (shore) objects.

During the summer, the ship and barge may leave the Detroit area for additional work in other parts of the Great Lakes. She may provide a floating home for researchers investigating water quality, or she might cruise to the top of Lake Superior to participate in military exercises. Summer is also a time for some repairs and refitting, perhaps made necessary from the winter ice-breaking duties, so a trip to the shipyards might be included. Lighthouse restoration and environmental protection are additional duties for the ship.

Once fall comes, the Bristol Bay begins the task of removing the floating aids from the surrounding waters. You might think that taking the buoys out is a little easier than putting them in, since you don't have to be so precise about locating them. However, if you give this some thought, you'll realize that an Aid-to-Navigation often marks a navagational hazard, and, once the aid has been removed, the hazard --now lurking unmarked-- still remains. The (unmarked) hazard is still as dangerous as it always was and must be avoided by the ATON ship that just removed it's buoy. Fall weather can be just as rotten as in the icy springtime, and to make things more difficult, anchors and anchor chains usually accumulate a coating of zebra mussels over the 8-10 months they've been in the water, adding thousands of little sharp edges to the handling of the navigation aids. (Not to mention a rather salty smell once they have died and begin to decay while out of the water.)

When ice conditions have laid up almost all other boats, the big freighters and ice-breakers like Bristol Bay keep working. Finally, even when the shipping season closes, the Coast Guard may have to mount wintertime Search and Rescue (SAR) missions and the Bristol Bay may be called to assist.

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Copyright © 1996, 1997 by James W. Hebert. All rights reserved.
Page Last modified: January 26, 1997;