MV Cowal in 1954. She inaugurated the regular Wemyss Bay to Rothesay car ferry service, on 1 October 1954 and remained in the upper Clyde for her whole career. From 1957 the three "A, B, C" sisters were working interchangeably. In May 1970, "Cowal" inaugurated a short-lived seasonal Fairlie-Tarbert-Brodick service. When this ended in September 1971, "Cowal" operated between Largs and Millport, until displaced in March 1972 by the former Skye ferry on the quicker Largs to Cumbrae Slip run. With linkspans at Gourock and Dunoon, the hoist-loading "Bute" and "Cowal" were restricted to the Wemyss Bay to Rothesay crossing, where "Cowal"
Lake Cowal benefits economically to the town of West Wyalong with increased employment. Barrick Gold was granted a "Section 90" by National Parks and Wildlife. Lake Cowal is known as the heartland of the Wiradjuri nation and is rich in artifacts. Wiradjuri elder Neville "Chappy" Williams led a campaign to save Lake Cowal and the Wiradjuri heartland. The Lake Cowal Campaign aims to prevent further gold mining by Evolution Mining in the environmentally-fragile area around Lake Cowal and to stop land degradation and possible toxicity problems from the mine and its tailing dams. The Wiradjuri people are being joined in their campaign