The Calmar Steamship Co. was a subsidiary of the Bethlehem Steel Co. which had operated since the 1920s on an intercoastal route linking the U.S Atlantic and Pacific Coasts via the Panama Canal.
After the end of World War II, the Calmar company operated ten Liberty-type ships and, in the early 1960s, the decision was made to replace six of its tired war-built ships with an equal number of larger and faster C-4 type vessels.
In 1964, arrangements were made with the government and six 523-foot, 15,000 dwt C-4 troopships were taken out of ‘mothball’ status at the National Defense Reserve Fleet at Suisun Bay, Calif., and converted at a total cost of $27 million into bulk cargo carriers.
Like their predecessors, the new ships sailed on a nine-day rotation carrying Bethlehem Steel products from Philadelphia and Baltimore to Long Beach, San Francisco, Portland, and Seattle on the westbound leg, and an eastbound return voyage with general cargo and lumber.
Each of the new C-4s was capable of carrying 5,000 tons more cargo than a Liberty-class ship, and, with a cruising speed of 17 knots, cut the westbound Baltimore-U.S. West Coast trip from 18 to 12 days.
The Calmar was built for the U.S. Navy in 1944 as the C-4-type cargo transport General O. H. Ernst by the Kaiser Co. at its yard in Richmond, Ca., before being converted into a troopship to serve in both the Atlantic and Pacific war zones during World War II.
On January 29, 1965, the new Calmar arrived on its Port of New York maiden call with a cargo of 5.5 million board feet of Pacific Northwest lumber aboard. At the time, the ship was the newest, largest, and fastest intercoastal ship in the U.S. merchant fleet.
Bethlehem Steel Co., once second only behind U.S. Steel as the largest steel producer in the world, decided to dissolve the Calmar Steamship Company and end its intercoastal service in 1975 when increasing competition from imported steel and a loss of market share to Canadian lumber mills forced the company to reevaluate its corporate business strategy.
That same year, the Calmar was sold to Venezuelan interests. Renamed Orinoco, it was put into service carrying bulk commodities along the East Coast of South America for five years before going to the scrapyard.