Canso Canal Operations

The Canso Canal is located in the Strait of Canso, which separates Cape Breton Island from the mainland of Nova Scotia. It links Chedabucto Bay to Northumberland Strait.

It’s open from April 14, 7:30 pm local time, to December 24, 7:30 local time, 24 hours a day, 7 days a week, unless otherwise advertised.

The Canal serves mostly commercial ships, 85%, which are owned and/or operated by:

• shipping companies
• fishermen
• government

How Canso Canal operates

A canal is a manmade waterway connecting two bodies of water. When one body of water is higher than the other, the canal uses a lock to compensate for the difference in water levels.

In the case of the Canso Canal, water levels can vary as much as a metre due to tidal differences. Also, the construction of the causeway diverted an enormous amount of water with a strong current through the canal.

To manage the high water-level differences and the strong current, the canal uses a tidal lock that consists of two sets of gates to allow ships to pass safely.

Typical operation of the canal locks is as follows:

1. When a ship approaches the canal, the first set of lock gates is slowly opened to equalize the water levels on both sides. The ship arrestor is placed in the raised position. If a ship approaches from the south, the swing bridge for the Trans-Canada Highway and the Cape Breton and Central Nova Scotia Railway must be rotated to allow the ship to pass. The north gates remain closed and the north ship arrestor is in the lowered position.
2. When water stabilizes, the ship enters the lock, the ship arrestor is lowered and the first set of gates closes behind the ship.
3. The ship is then moored while the second set of gates at the other end of the lock opens and the ship arrestor is raised. The water between the gates once again stabilizes at the same level as the second body of water to which the vessel will be exiting.
4. The ship is then permitted to safely leave the canal.

History and key facts

Strait of Canso becomes as a passageway

• The Mi'kmaq were the original settlers in the area until the 1780s, when other settlements were established on both shores.
• Fishermen used the Strait of Canso as a passageway between the Atlantic Ocean and the Gulf of St. Lawrence, establishing the Strait as a water route. Eventually coastal freighters used the deep waters of the Strait of Canso, and later oil tankers. Ferries also used the Strait of Canso to transport trains and vehicles between the two shores.
• Sailing through the Strait saved time and fuel costs. It trimmed 70 nautical miles off the voyage to Montreal and 171 nautical miles off a trip to Charlottetown versus sailing around the tip of Cape Breton.

Need for a causeway and canal grows

• As vessel traffic congestion on both sides of the Strait increased, demand for a permanent crossing grew.
• The creation of a causeway and canal complex was announced in 1951.
• The Canso Causeway joined Cape Breton Island to mainland Nova Scotia, but it also blocked marine traffic from travelling between the Gulf of St. Lawrence and the Atlantic Ocean through the Strait of Canso.

Construction of Canso Canal

• The work on Canso Canal began in 1953 under a tri-party agreement between:
  • the federal Department of Transportation
  • the Nova Scotia Department of Highways
  • Canadian National Railway
• Balhache Point, also known as MacMillan Point, just off Port Hastings, was selected as the site for the canal construction. It was cheaper to drill, blast and dig the canal through the point than any other option.
• The soil and rock that was removed was used as fill for the rest of the canal site.
• Close to 700 metres of temporary steel enclosure had to be built to keep the waters of the Strait out of the construction site.
• The canal is 250 m long, 24.4 m wide and 9.8 m deep at low tide. It makes it compatible with the St. Lawrence Seaway, capable of passing a ship 224 m in length, with a draft not exceeding 8.5 m.
• The Canso Canal was opened to shipping traffic on September 2, 1955. It allowed the continued movement of marine traffic between Chedabucto Bay and St. George's Bay.
• The Donna Louise, a fishing boat owned by Capt. Tom Dodge, was the first ship to travel through the canal.
• On average a 1,000 ships with gross tonnage of 500,000 pass through the canal annually from Chedabucto Bay to St. George's Bay and vice versa. The remaining 15% are pleasure craft users.
• The Government of Canada owns the Canso Canal, under the custodianship of the Department of National Defence, and the Canadian Coast Guard (CCG) Atlantic Region operates it.