The St. Lawrence River is one of the largest inland waterways in the world. Its channel, which is 11.3 metres (37 feet) below the lowest water line (chart datum), is open year-round to all types of ships, including containerships that can carry as many as 4,100 TEU (twenty-foot equivalent unit) containers.

Whether on ships or at its terminals, work at the Port of Montreal is relentless when it comes to providing year-round, first-rate service – and it has been that way for close to 40 years.

In 1964, the Canadian Coast Guard began to use icebreakers to keep the navigation channel open, first and foremost as an environmental measure designed to protect riverside communities from spring floods caused by ice jams. The practice continued, and ever since, winter and navigation at the Port of Montreal have gone hand in hand.

Ice breaking has made winter navigation possible, but so has the arrival of ships with reinforced hulls and high-tech navigational aids, and the construction of major ice-control works at strategic locations along the river.

The Canadian Coast Guard (CCG) facilitates commercial navigation in many ways: through co-ordination and deployment of icebreakers, helicopter surveillance, and rapid and effective transmission of information to navigators.

The following are just some of the measures the CCG has put in place to improve winter navigation:

• The installation of steel ice booms to speed up the more effective formation of a solid, protective ice cover outside the shipping channel of Lake St. Pierre (some 100 kilometres downstream from Montreal) and other strategic locations. This prevents the production of loose ice and strengthens the current, accelerating ice evacuation;
• A system to measure in real-time the tension of the protective ice cover on ice booms;
• The restoration of artificial islands on Lake St. Pierre to stabilize the protective ice cover on the lake;
• An improved video camera surveillance network that instantaneously transmits images of ice movements to icebreakers, helping improve response time;
• A new sonar detection system that monitors ice movements in the channel, further improving the ability to foresee and prevent potential ice jams.

For safe navigation
Extremely competent pilots and the Canadian Coast Guard ensure navigational safety on the St. Lawrence. A computerized system of 13 electronic readers located between Montreal and Quebec City helps to optimize the loading of deep-draught vessels by continuously communicating water levels. Vessels also benefit from satellite-navigation technology and electronic marine charts. An elaborate radio-communications system regularly transmits navigational conditions on the river.