In 1920, after 87 years in the making, the federal government completed the lock system on the Trent-Severn Waterway, connecting Lakes Ontario, Simcoe, and Huron. The 368-km route, developed for trade and defence, had been previously portaged by Indigenous and European travellers for centuries. Now featuring 40-plus locks, 50 km of canals, and 150 dams, it allows boats to cruise across cottage country without ever leaving the water.
Well, just once.
Lock 44 in Coldwater, Ont.—the Big Chute—carries boats over an 18-metre hill that breaks up the Severn River using the only marine railway in North America. While conventional locks raise or lower boats by adjusting water levels in a chamber, the Big Chute pulls vessels on a cable-drawn, winch-powered rail carriage.
Epic photos from the Parks Canada Lock & Paddle event
“The railway was meant to be a temporary measure until after World War I,” explains Dennis Carter-Edwards, the former cultural resources manager of the Trent-Severn Waterway. The original structure, operational as of 1917, only lifted boats up to 11 metres and 5 tonnes, and when the carriage reached the hill’s summit, operators manually rehooked the cable on the other side of the platform to begin lowering it. However, post-war government funding cuts cancelled the locks and canal, leaving the small railway to complete a passage linking the Severn River and Gloucester Pool. “Tourism promoters pressured the government to maintain the waterway in the 20th century,” says Carter-Edwards. “Particularly in the Severn River, boating was booming.” Rebuilds in 1923 and 1978 made the Big Chute’s platform bigger, its tracks wider, and its winch stronger (and automatic) to accommodate bigger vessels. Today’s carriage hauls boats around 30 metres long and as heavy as 90 tonnes.
The Big Chute lifts dozens of boats daily in the summer, but more substantial is what it doesn’t transport. When rebuilding the railway in 1965, the government ruled out replacing it with a conventional lock; retaining a land obstacle in the Severn had prevented sea lamprey, a parasitic, invasive species, from reaching in-land lakes.
In 1929, the TSW became a National Historic Site; it takes seven days to travel. Big Chute is followed only by Port Severn’s Lock 45—saving the best for (second) last?
This article was originally published in the Early Summer 2026 issue of Cottage Life.
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