Built in 1977, by St. Louis Ship of St. Louis, Missouri (hull #3596) as the Ed Renshaw for Federal Barge Lines Incorporated of St. Louis, Missouri.

In 1984, the tug was acquired by Midland Enterprises Incorporated of Cincinnati, Ohio. Where she retained her name.

In 2003, she was acquired by Ingram Barge Company of Nashville, Tennessee. Where the tug retained her name.

In 2010, the Ingram Barge Company renamed the tug as the Mary K. Cavarra.

Powered by two, GM 16-645E7B diesel engines. With Falk reduction gears, at a ratio of 4.345:1. Turning two, fixed pitch propellers mounted in kort nozzles. She is a twin screw towboat, rated at 6,120 horsepower.