Into the 1920s, the Moyie continued as a relief vessel. Her duties were many and varied and, except for refitting, she appears to have been in almost constant service—on average, all but one or two days a month. She was sometimes used as a tug on the Procter–Kootenay Landing Route, but more often she worked barges around the lake on a varied daily schedule that saw the steamer leaving early in the morning and not tying up until late in the evening. With a crew comprised of from 14 to 21 men, she hauled such commodities as powder, oil, apples, lumber, coal and ore concentrates.
The Moyie was also used on excursions during this period and as many as 200 passengers were carried. For example, on July 30, 1924 an excursion was operated between Nelson and Procter with 217 people on the eastbound trip and 183 returning to Nelson late in the day. Nelson to Procter and Nelson to Kaslo were favourite excursion routes. Vessels were operated to Kaslo as a traditional part of the May 24th holiday celebrations.
The extension of the CPR mainline along the West shore of Kootenay Lake in December 31, 1930, enabled the railway to retire its mainline steamer and tug and barge service on Kootenay Lake, leaving only limited passenger and barge service to outlying points along the lake. With the retirement or sale of all vessels except the S.S. Moyie (and S.S. Granthall, her relief vessel), a new pattern of operation was established that remained in place until the retirement of the Moyie in 1957. Based at Procter, the Moyie provided once-weekly scheduled passenger service to Kaslo and other lake points and also moved railcar barges (transfer barges) to Lardeau and Riondel as required. The Moyie also continued to provide excursion service on the lake.
The day-to-day routine was not significantly different from the previous period in the vessel’s history, but the passenger service standards were lower and the Moyie was part of a much smaller operation. Her role was equivalent to the service provided by a mixed train on a branch line of the railway. The Moyie also served as a relief vessel for the government ferries crossing Kootenay Lake when they were being refitted.
By the 1950s the Moyie had become, in effect, a sternwheeled, passenger carrying tug, a role she was not originally designed to fill but had been doing so effectively for many years. On April 27, 1957, the Moyie was retired from CPR service. At high water the next spring, the vessel was moved to Kaslo and beached. The City of Kaslo had purchased the SS Moyie from the Canadian Pacific Railway for $1.00. To oversee preservation of the ship, the Kootenay Lake Historical Society (KLHS) was incorporated under the Societies Act on June 12, 1958, with the mandate to preserve and maintain the 1898 CPR passenger sternwheeler, and to promote awareness of Kaslo and area’s local history.
Since then a dedicated group of volunteers has brought the ship through 40 years of fundraising, preservation and restoration to see her celebrate her 100th year in 1998. In 2002, the site welcomed over 25,000 tourists: 12,500 visitors from around the world toured the ship. With an active Board and membership of over 200, the KLHS distributes periodic newsletters and participates in various community events. With the Moyie’s restoration phase nearly complete, the Kootenay Lake Historical Society is currently developing a long-range business plan to carry the ship into her next 100 years.