[6] The destroyers were also equipped beginning in 1958 with Mk 43 homing torpedoes in an effort to increase the distance between the ships and their targets.

[7] St. Croix, named for a river in New Brunswick, was laid down on 15 October 1954 by Marine Industries at Sorel, Quebec.

The ship was launched on 17 November 1956 and commissioned into the Royal Canadian Navy on 4 October 1958 with the classification DDE 256.

[8][9] The following year, with sister ships Terra Nova, Kootenay and Gatineau, she took part in the 500th anniversary of Prince Henry the Navigator's death off Lisbon.

[8] St. Croix, along with Columbia and Chaudière, was one of three Restigouche-class vessels not selected for modernization in the Improved Restigouche (IRE) project of the late 1960s.

[11] In 1967 and 1969, the ship made long cruises across the Pacific, visiting Hawaii, Fiji, Australia and New Zealand.

She was paid off on 15 November 1974 at Halifax, Nova Scotia and placed in reserve as economies required by government reductions in authorized strength.