Built in 1980, by Superior Boat Works Incorporated of Greenville, Mississippi (hull #144) as the Theresa L. for Lalande Towing Incorporated of New Iberia, Louisiana.
In 1981, she was sold. And, renamed as the Mary Read Harrison.
In 1997, the tug was acquired by Dixie Marine Incorporated of Houston, Texas. Where the tug was renamed as the Comal.
In 1998, she was acquired by the Kirby Corporation of Channelview, Texas. Where the tug retained her name.
Powered by two, Volvo D12 diesel engines. She is a twin screw, towboat, rated at 900 horsepower.