Lock 42 Couchiching marks a pivotal transition for Great Loop cruisers. After crossing the expanses of Lake Simcoe and Lake Couchiching, Loopers enter the manmade Trent Canal and descend through this lock into the Severn River — the final river system before reaching Georgian Bay. From here, only three locks remain between you and open Great Lakes water, and the landscape shifts decisively from cottage-country lakes to the rugged granite and pine of the Canadian Shield. Learn more at AGLCA: https://www.greatloop.org/
Lock 42 Couchiching sits in the manmade Trent Canal at approximately KM 337.8 (Mile 209.9), roughly 3.2 kilometres south of the point where the canal meets the Severn River. Vessels approaching from Lake Couchiching enter a narrow, ruler-straight channel that local boaters call the “Bowling Alley” — a two-mile stretch with a strictly enforced 6 mph speed limit. This lock is the critical control point where the waters of Lake Simcoe and Lake Couchiching are released westward into the Severn River system, ultimately flowing to Georgian Bay. Situated in the Township of Severn near the community of Washago, Lock 42 holds the distinction of being the last lock constructed on the entire Trent-Severn Waterway.
Construction of Lock 42 began in August 1914 as part of the Severn Division, but wartime material shortages forced work to halt in 1917. The project resumed in 1919 and the lock was officially opened in July 1920, completing the final navigable link in the 386-kilometre waterway between Lake Ontario and Georgian Bay. The lock has a CHS-charted lift of 6.4 m (21 ft), though Parks Canada lists the average lift as 6.2 m (20 ft) — boaters should be aware of this minor discrepancy between sources. A highway bridge (Bridge 56) with a vertical clearance of 9.4 m (31 ft) and an overhead power cable with a clearance of 10.1 m (33 ft) cross the canal at the lock. The fixed bridge was fully replaced in 2019–2020 as part of Parks Canada’s infrastructure investment program.
Lock 42 is a very busy station on summer weekends, as it serves all traffic transiting between Lake Simcoe and Georgian Bay. Overnight mooring is available for a maximum of one night with a valid pass. The lockstation offers washrooms, showers, potable water, a picnic area, and ice. A general store and snack bar operate near the lock, and the Lock42 Grill restaurant is located approximately 100 metres away on Bonsor Road. There is no electrical hookup at this station. Immediately below the lock, the canal joins the Severn River and the main route proceeds west through Sparrow Lake toward Swift Rapids (Lock 43) and Big Chute (Lock 44) — the final stretch before Georgian Bay.
| Official Name | Lock 42 — Couchiching Parks Canada |
| Lock Number | 42 |
| GPS Coordinates | 44°46’11”N, 79°21’01”W Parks Canada |
| Street Address | 4375 Canal Road, Washago, ON L0K 2B0 Parks Canada |
| KM Marker | KM 337.8 Mile 209.9 TSW DB |
| Region | Township of Severn, Simcoe County |
| Water Body | Trent Canal at Severn River Junction |
| CHS Nautical Chart | #2028-2 / #2029-1 CHS |
| Nearest Municipality | Washago, Ontario |
| Historic Construction | Commenced August 1914; opened July 1920 Parks Canada |
| Lock Phone | 705-689-2182 [VERIFY — Parks Canada] |
| trentsevern@pc.gc.ca |
| Parameter | Metric | Imperial |
|---|---|---|
| Lock Number | 42 | |
| Average Lift | 6.4 m | 21 ft |
| Chamber Length | 47.2 m | 155 ft |
| Chamber Width | 9.7 m | 32 ft |
| Maximum Draft System-wide | 1.8 m | 6 ft |
| Gate Type | Standard mitre | |
| VHF Channel | Channel None | |
| Operating Season Parks Canada | Mid-May to mid-October | |
| Max Mooring Period Parks Canada | 2 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) 689-2182 | |
▲ Above Lock
▼ Below Lock
▲ Above Lock
▼ Below Lock
📌 ~6 km from lock
🌊 Depths: 4/5 ft (approach/dock)
📍 GPS: 44.7717°N, 79.3503°W · 4375 Canal Road, Washago, ON L0K 2B0, City of Orillia, Ontario, ON · Get Directions ↗ · Street View ↗
For navigation, use CHS Chart #2025 — this map is for reference only and should not be used for marine navigation.
☎ Muskoka Taxis — (705) 687-2111 — 24/7. Covers Washago, Orillia, Gravenhurst, and Muskoka. Wheelchair accessible vehicles. Pre-payment required for reservations. 🔗
☎ Ontario Northland Bus — 1-800-461-8558 — Intercity bus stop at 3384 Muskoka St (Toronto—North Bay corridor). Not all routes stop here — check schedule. 🔗
☎ Via Rail (Washago Station) — 1-888-842-7245 — First stop after Toronto on The Canadian transcontinental. Unstaffed, infrequent — check schedule well in advance. 🔗
No Uber/Lyft confirmed in this area.
Boater Orientation Notes:
- Lock 42 is ~3.5 km from downtown Washago — only Lock 42 Grill (~100 m) is walkable. All other services require taxi (~5—7 min).
- Overnight mooring limited to one night. Bridge crosses lower lock walls — expect traffic noise overnight.
- Canoe Fresh Food Market on Muskoka St is the best provisioning stop — artisan grocery with bakery, deli, cafe, and famous butter tarts.
- McGregor on the Water Marina (~1.7 mi south by boat before entering the canal) has fuel, pump-out, repairs, and haulout — call (705) 689-9935.
- The 2-mile canal from Lake Couchiching (the “Bowling Alley”) has a 6-mph speed limit. Hamlet Swing Bridge after Lock 42 — current can be strong; slow down and announce approach.
🛒 Grocery
| Name | Directions | Phone | Rating | Distance | Access |
| Canoe Fresh Food Market 🔗 | Let’s Go! | (705) 514-5000 | ⭐ 4.6 | 3.5 km | Short Drive |
| Houston’s Village Grocery | Let’s Go! | N/A | ⭐ N/A | 3.5 km | Short Drive |
| LCBO Washago 🔗 | Let’s Go! | (705) 689-0994 | ⭐ N/A | 3.0 km | Short Drive |
| Washago Variety | Let’s Go! | N/A | ⭐ N/A | 3.5 km | Short Drive |
🍴 Restaurants
| Name | Directions | Phone | Rating | Distance | Access |
| Lock 42 Grill 🔗 | Let’s Go! | (705) 689-4242 | ⭐ 4.6 | 100 m | Walkable |
| Blue Moon Junction Cottage Bar and Grill 🔗 | Let’s Go! | (705) 689-0782 | ⭐ 4.3 | 4.5 km | Short Drive |
| Kim’s Kitchen | Let’s Go! | (705) 689-6522 | ⭐ 4.2 | 3.5 km | Short Drive |
| Scoopz Ice Cream 🔗 | Let’s Go! | N/A | ⭐ 4.9 | 3.5 km | Short Drive |
🏛 Local Interests
| Name | Directions | Phone | Rating | Distance | Access |
| Lock 42 — Couchiching (Parks Canada) 🔗 | Let’s Go! | (705) 689-2182 | ⭐ N/A | On-site | Walkable |
| Art Gallery of Washago | Let’s Go! | N/A | ⭐ N/A | 3.5 km | Short Drive |
| Washago Centennial Park and Beach 🔗 | Let’s Go! | N/A | ⭐ N/A | 4.0 km | Short Drive |
🔧 Support & Services
| Name | Directions | Phone | Rating | Distance | Access |
| Ben’s Washago Pharmacy | Let’s Go! | (705) 689-5515 | ⭐ N/A | 3.5 km | Short Drive |
| JRK Marine 🔗 | Let’s Go! | N/A | ⭐ N/A | N/A | Short Drive |
| McGregor on the Water Marina | Let’s Go! | (705) 689-9935 | ⭐ N/A | 1.7 mi by water | Short Drive |
| Washago Home Hardware 🔗 | Let’s Go! | (705) 689-2611 | ⭐ 4.8 | 3.5 km | Short Drive |
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 #2025 before transiting. CHS CEN309
Shoal locations, rock hazards, and current data for Lock 42 – Couchiching 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 ↗
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