Manson is one of the nation’s leading heavy civil marine construction and dredging companies. We take great pride in our reputation for safely completing our work on time and on budget. Established in 1905, Manson began as a small, family-owned Puget Sound marine pile driving business. Today, Manson thrives as an employee-owned company with a second, third and even fourth generation workforce. Our fleet of heavy marine construction and dredging equipment includes 60 specialized vessels and over 50 barges. Headquarters remain in Seattle, though we have expanded to include permanent facilities in Northern and Southern California, Louisiana, and Florida.