Ocean Completes Sept-les Maintenance Job Using Clamshell Dredge
On the March-April cover: A 16-cubic-yard Cable Arm bucket on the dredge Ocean Borromée Verreault prepares to unload into a barge during a maintenance project at Sept-Îles on the St. Lawrence River in Quebec. Hughes Douville watches as operator André Gauthier maneuvers the bucket.
André Gauthier, Hughes Douville and a deckhand rig the Cable Arm bucket.
The Ocean Borromée Verreault is equipped with a Liebherr 895 crane, mounted on a spud barge.
Last year, Quebec-headquartered Ocean performed a maintenance contract for the Port of Sept-Îles using its clamshell dredge Ocean Borromée Verreault. Sept-Îles is on the north shore of the St. Lawrence River, 325 miles east of Quebec City. The project included dredging the multi-users wharf #35 at Pointe Noire.
Working from August 6 to October 15, the dredge removed 350,000 cubic yards of material using a 16-cubic-yard CableArm environmental bucket with a 15-foot by 16-foot open footprint. The bucket was designed with an open center to increase lowering speed. The material was a clean, plastic clay, which could be placed in an in-water site a half mile from the dredge. The round trip was about 20 minutes.
The OBV dredge is Liebherr 895 crane mounted on a 140-foot by 45-foot barge. The dredge has three 100-foot spuds, two welding machines, two compressors, a Hiab deck crane used to load equipment and the small 20 by six-foot tender boat. There are two drum winches to handle the anchors. One of Ocean's 4000-hp tugs with Z-drive moves and positions the dredge.
Ocean used its two self-propelled, 225-cubic-yard, 250 hp bottom dump scows on the project. Each scow has a bow and stern thruster driven by a 180 hp engine, and can achieve up to eight knots.
The Bay of Sept-Îles is shaped like a horseshoe with Pointe-Aux-Basques and Pointe a la Marmite forming its two points. Its entrance, protected by the seven islands, can be accessed by three channels (the eastern, western and the middle channel).