September 4, 2019 – Responding to a request from U.S. Naval Forces Europe and U.S. Army Europe to remove a sunken dredge barge from the port of Alexandroupoli, Greece, NAVSEA Supervisor of Salvage and Diving, SEA 00C, has developed a plan and assembled a team to remove the barge and restore access to the pier for future NATO missions.
The dredge barge, Olga, which has laid on the harbor bottom since 2010, is over 150’ long and weighs approximately 800 metric tons. The barge is laying on its side and blocking the center portion of the 500’ long cargo pier which represents a vital asset for NATO logistics operations.
Following a site survey in June, SUPSALV returned in early August with their team to begin vessel removal. The team consists of NAVSEA salvage engineers, a salvage master from SUPSALV’s Atlantic region salvage contractor, DONJON, and a Greek salvage company, Five Oceans, supported by a local dive team.
Using the crane barge Hercules, the salvage team’s plan is to section the barge using a chopping beam (also known as a crane chisel) into 30-ton hull sections for lift and removal. When this technique is effective, large sections can be quickly removed and processed for scrap. The following image shows a section of the hull sitting on a trailer, demonstrating the effectiveness of this method.
This dredge barge was a very complex and unwieldy vessel. There are portions of the vessel where the removal of clean hull sections is complicated by an immense layer of entangled debris made up of the dredging equipment, booms, buckets, chain, and remnants from previous salvage attempts. This layer of debris prevents an effective strike from the chopping beam and therefore the loose debris must be removed first. The following image shows an example of a lift of debris which was cut free by divers to allow access to the hull sections beneath.
The team makes progress daily and plans to continue removal operations through the end of October when 500 ft of additional pier space in Alexandroupoli, Greece will be available for future NATO operations.