Big Chute is the moment every Looper remembers. Your vessel is floated onto a motorized steel cradle, lifted clear of the water, and transported overland on rails across the granite ridge separating the Severn River from Gloucester Pool. Nothing else on the entire 6,000-mile Great Loop compares to riding your own boat down an inclined plane while dry land passes beneath your keel. Georgian Bay is now just one lock away at Port Severn — the final gateway to open water. Learn more at AGLCA: https://www.greatloop.org/
Lock 44 Big Chute sits at Kilometre 374 on the Severn River, deep in the Canadian Shield country of the Township of Georgian Bay. It is the only marine railway of its kind in North America and the most distinctive structure on the entire Trent-Severn Waterway. Rather than raising or lowering vessels within a water-filled chamber, Big Chute uses a motorized steel carriage running on four parallel rails to haul boats completely out of the water and transport them overland across the granite ridge that separates the upper Severn River from Gloucester Pool — a vertical change of 17.7 m / 58 ft. From here, Georgian Bay lies just 13 km / 8 miles downstream through Gloucester Pool, with only Lock 45 at Port Severn remaining before open water.
A marine railway has operated at Big Chute since 1917, when wartime shortages of manpower and concrete prevented construction of the conventional lock originally planned. That first railway could carry only one vessel at a time and had a capacity of just 18 tonnes. It was replaced in 1923, and the current marine railway opened to the public in 1978. The modern carriage is 24.4 m / 80 ft long, rides on four parallel rail tracks, and is hauled by four steel wire ropes powered by four electric motors. It can transport up to nine smaller vessels at once, arranged three abreast in individual adjustable slings. Lock 43 at Swift Rapids also operated as a marine railway from 1917 until it was replaced by a hydraulic lock in 1965, making Big Chute the sole surviving marine railway on the waterway. The facility also serves a critical environmental role — by lifting vessels clear of the water rather than passing them through a shared water chamber, the railway helps prevent the spread of invasive sea lamprey into Lake Simcoe and the inland lakes.
Approaching from upstream, vessels tie to the painted blue line on the port-side wall or secure to one of two floating docks extending into the staging basin. Parks Canada staff call vessels to the carriage over a loudspeaker — the first boat on the blue line is not always the first called. Remove all fenders before driving slowly onto the carriage, where the crew positions the vessel in adjustable slings. The overland transit takes approximately seven minutes as the carriage creeps across the road and down the incline to the lower reach. Larger vessels rest directly on the carriage platform rather than being suspended in slings. Below Big Chute, be aware that considerable discharge from the adjacent power generating station creates a cross current, and the winding channel through Little Chute approximately 1.6 km / 1 mile downstream narrows to just 15.2 m / 50 ft with strong variable current.
| Official Name | Lock 44 — Big Chute Marine Railway Parks Canada |
| Lock Number | 44 |
| GPS Coordinates | 44.8842°N, 79.6715°W [VERIFY — Parks Canada] |
| Street Address | 7001 Upper Big Chute Rd, Coldwater, Ontario Parks Canada |
| KM Marker | KM 374 / Mile 232.5 CHS CEN309 |
| Region | Township of Georgian Bay, Ontario |
| Water Body | Severn River — Upper Severn to Gloucester Pool |
| CHS Nautical Chart | #2029-1 CHS CEN309 |
| Nearest Municipality | Coldwater, Ontario |
| Historic Construction | First marine railway 1917; replaced 1923; current railway opened 1978 Parks Canada |
| Lock Phone | (705) 756-8802 Parks Canada |
| trentsevern@pc.gc.ca |
| Parameter | Metric | Imperial |
|---|---|---|
| Lock Number | 44 | |
| Average Lift | 17.68 m | 58 ft |
| Chamber Length | 30.5 m | 100 ft |
| Chamber Width | 7.3 m | 24 ft |
| Maximum Draft System-wide | 1.8 m | 6 ft |
| Gate Type | Marine railway | |
| VHF Channel | Channel None | |
| Operating Season Parks Canada | Mid-May to mid-October | |
| Max Mooring Period Parks Canada | 5 nights | |
| Permit Required | Yes — 1‑888‑773‑8888 or parks.canada.ca | |
| Electricity | ✗ Not Available | |
| Potable Water | ✔ Available | |
| Pump-Out | ✗ Not Available | |
| Operator | Parks Canada — Environment and Climate Change Canada | |
| Lock Phone Parks Canada | (705) 756-8802 | |
▲ Above Lock
▼ Below Lock
📍 GPS: 44.8847°N, 79.6742°W · 7001 Upper Big Chute Rd, Coldwater, Ontario, Severn Township, Muskoka, Ontario, ON · Get Directions ↗ · Street View ↗
For navigation, use CHS Chart #2029-1 — this map is for reference only and should not be used for marine navigation.
☎ Big Chute Marina — Seasonal Water Taxi — (705) 756-2641 — Seasonal water taxi between Lock 44 (Big Chute) and Lock 43 (Swift Rapids). On-water transportation only — inquire at marina for availability. 🔗
No road taxi, rideshare (Uber/Lyft), or public transit service available at Lock 44. This is one of the most remote locations on the entire TSW.
Boater Orientation Notes:
- Lock 44 is one of the most remote locations on the TSW — ~20 km north of Coldwater, ~15 km east of Port Severn. No confirmed road taxi or transit.
- Big Chute Marina (~200 m, across the road) is the ONLY commercial business within walking distance — restaurant, variety store, fuel, propane, and marine services.
- Nearest grocery, LCBO, pharmacy, hardware, and laundromat are in Port Severn (~15 km) or Coldwater (~20 km) — both require a vehicle.
- Max mooring at blue line: 2 nights. Parks Canada boater camping permitted on lock grounds. Visitor Centre has observation deck and interpretive displays.
- Big Chute Marina has gas (no diesel), pump-out, propane exchange (20/30/100 lb), transient slips to 45 ft, and monitors VHF Ch 68.
🛒 Grocery
| Name | Directions | Phone | Rating | Distance | Access |
| Big Chute Marina Store 🔗 | Let’s Go! | (705) 756-2641 | ⭐ 4.2 | 200 m | Walkable |
🍴 Restaurants
| Name | Directions | Phone | Rating | Distance | Access |
| Big Chute Marina Restaurant 🔗 | Let’s Go! | (705) 756-2641 | ⭐ 4.2 | 200 m | Walkable |
🏛 Local Interests
| Name | Directions | Phone | Rating | Distance | Access |
| Big Chute Hydro Generating Station — Interpretive Display | Let’s Go! | N/A | ⭐ N/A | 200 m | Walkable |
| Big Chute Marine Railway — Parks Canada Visitor Centre 🔗 | Let’s Go! | (705) 750-4900 | ⭐ 4.8 | On-site | Walkable |
| Big Chute Picnic Grounds and Boater Campground 🔗 | Let’s Go! | (705) 750-4900 | ⭐ N/A | 100 m | Walkable |
| Old Marine Railway (Little Chute) — Historic Site | Let’s Go! | N/A | ⭐ N/A | 300 m | Walkable |
🔧 Support & Services
| Name | Directions | Phone | Rating | Distance | Access |
| Big Chute Marina — Marine Services 🔗 | Let’s Go! | (705) 756-2641 | ⭐ 4.2 | 200 m | Walkable |
Last Updated: March 18, 2026
Post-Kirkfield: red and green channel buoys are on opposite sides from the lower system. Red-right returning applies southbound, not northbound. Verify with CHS Chart #2029-1 before transiting. CHS CEN309
Shoal locations, rock hazards, and current data for Lock 44 – Big Chute Marine Railway are being compiled from CHS CEN309 and current Notices to Mariners. Check notmar.gc.ca for active advisories. CHS
Weather data for navigation planning purposes only. Always check Environment and Climate Change Canada’s official marine forecast before making operational decisions. weather.gc.ca ↗