Dredge Merritt to Undergo Major Maintenance

Merritt arriving at Ensley Engineer Yard for major upgrades. (Photo by Ken Williams)

The U.S. Army Corps of Engineers Dredge Merritt, homeported in the Corps’ Wilmington District, has arrived at Memphis District’s Ensley Engineer Yard where the vessel will undergo major maintenance to extend its service life.

According to the Corps, the vessel left Wilmington on October 19th for the long voyage around the coast to Mobile, Ala., up the Tennessee–Tombigbee Waterway to the Ohio River and finally down the Mississippi River to Memphis.

This is the first time we’ve had this type of dredge at Ensley Engineer Yard,” Tim Fudge, Memphis District’s Operations Division Chief said. “We’re excited about this opportunity to put our skills to work on it and help out one of our sister districts maintain their readiness.”

Andrea Williams – project manager for this work and Chief of the Memphis District’s Plant Section – said that the centerpiece of this large project is to “rehull” the Merritt. In other words, Ensley workers will remove all of the existing plating from the hull of the dredge and replace it with new steel.

We also plan to do some work on the framing (the skeleton of the vessel), and replace the potable water and marine sanitation device tanks,” she said.

The 104-feet-long Merritt is a side-cast dredge and typically works in the numerous inlets along the South Atlantic coast. Unlike the dredges used on the Mississippi and other inland rivers, the Merritt has two drag arms on each side of the vessel that operators lower into the water.

The dredge removes sediment from the bottom and pumps it through a discharge pipe outside of the channel and into the direction of the current. It can dredge to a depth of up to 20 feet.

The Merritt is especially suited for maintenance of shallow, un-stabilized inlets where larger hopper dredges cannot operate due to strong currents and ocean environment. It often works with hopper and larger side-casting dredges by constructing pilot channels across limiting shoals, and widening channels into high bank areas.

Built in 1944 at the U.S. Navy Yard in Charleston, S.C., and designated YSD-59 – a Seaplane Wrecking Derrick, it carried a ten ton revolving crane to salvage downed seaplanes in harbors. The Corps of Engineers later acquired the vessel and converted it to a dredge in 1964.

Workers at Ensley Engineer Yard plan to spend about 10 days initially preparing the Merritt, then will raise it in the Memphis District’s large floating Drydock 5801 to begin the rehulling process. Williams said that they plan to complete work on the dredge around March 30, 2018.