Engine technology that’s proven itself onboard tankers, cargo vessels and cruise ships has now made its way to the dredge market. The new General MacArthur, the largest fully diesel-electric dredge of its kind in North America, gets its power from three MaK™ 12M 32 C generator sets producing a total of 24,000 hp (18,000 kW).

A cutter suction dredge, the General MacArthur is owned and operated by Callan Marine, a family-owned dredging business that works to facilitate transportation on U.S. waterways. That includes restoring berthing depths for ship docks and navigation channels, as well as marsh creation and beach re-nourishment. Callan Marine and the company it acquired in 2017, Bean Coastal, were longtime Cat® marine engine customers, but this was the Texas-based business’s first experience with MaK.

“They approached us with the idea of building a large diesel-electric dredge, mostly to improve the overall efficiency of dredge operation itself,” says Chandler Cleveland, general manager with Resource Power Group, an MaK marine dealer that’s a subsidiary of Cat dealer Louisiana Cat. “They were looking for high-output engines and wanted to stay in the Cat family. They toured our facilities, saw our inventory and met our product support staff, and that made them comfortable going with MaK.”

 Efficient power for work and life onboard

The General MacArthur’s three MaK generator sets provide electricity for everything onboard that operates on electric power, including the electric motors that drive the cutter head loosening the dredge material on the ocean floor and the pumps removing the dirt and silt through a steel, large-diameter pipeline to the placement area(s).

“With electric power, they can get to work right away versus traditional engines that have to ramp up before dredging can begin,” Cleveland says. “The generators also run at an optimal range all the time, which could be a money-saver for them.”

The MaK generator sets don’t just power the General MacArthur’s work, however. They also power the onboard accommodation, which on this 290-foot vessel are significant. The new dredge is built with all the modern conveniences today’s workforce demands — including a full galley, gym, TV/rec room, laundry facility, conference room, 33 cabins with private bathrooms and staterooms for the captain and chief engineer. That allows the crew to stay onboard for long stretches of time and operate the dredge 24 hours a day on different shifts.

“Typically a dredge would have engines for dredging plus auxiliary generator sets for these accommodation loads, but the General MacArthur gets it all from the MaK power plant,” Cleveland says. “This is a new, market-leading way to operate that we hope becomes a trend.”

Also onboard are individual Cat C18 and C4.4 generator sets, which can be used for back-up or emergency power or to run hotel loads when the vessel isn’t dredging.

Team effort brings vessel to life

Nothing like the General MacArthur had ever been built at the C&C Shipyard in Belle Chasse, Louisiana, and the SPI/Mobile Pulley Works Shipyard in Mobile, Alabama. Design and construction required a large team made up of representatives from Callan Marine and both shipyards plus support from MaK and Caterpillar. That included a service engineer, technical service manager and project manager from Resource Power Group who had experience in diesel-electric projects in other applications, along with the head electrical commissioning engineer from Louisiana Cat.

“Together, we all helped take the idea Callan Marine had and turned it into reality,” Cleveland says. “They had confidence in us since we were there from the beginning.”

Cleared by the U.S. Coast Guard and classified by the American Bureau of Shipping in May 2020, the General MacArthur has the capability to work on all U.S. coasts and waterways. One of its first projects is to continue the deepening and widening of one of the nation’s key energy transportation channels, as part of Phase II of the Corpus Christi Ship Channel Improvement program.