Built in 1989, by North American Shipbuilding Incorporated of Larose, Louisiana (hull #133) as the C-Tractor 1 for Edison Chouest Offshore Incorporated of Galliano, Louisiana.
In 2005, the tug was acquired by the Bay Houston Towing Company of Houston, Texas. Where she was renamed as the William M.
Powered by two, sixteen cylinder, EMD 16-645 diesel engines. With Ulstein z drive units located forward. Outfitted with two, bronze, fixed pitch propellers. For a rated 4,100 horsepower.
Her electrical service is provided by two, 150kW generator sets. The tug's capacities are 41,475 gallons of fuel, and 43,588 gallons of ballast.