Great Lakes Dredge & Dock Company, LLC | 25,523 followers on LinkedIn. IT ALL STARTS WITH DREDGING | Great Lakes Dredge & Dock (GLDD) is the largest provider of dredging services in the United States and the only U.S. company with significant international dredging operations. GLDD employs more than 1,000 dedicated engineering, operations, and support personnel. GLDD has a rich 135-year history of developing and executing successful dredging and marine construction projects, operating the largest and most diverse dredging fleet in the U.S. comprising approximately 200 specialized vessels.