| The users are certainly willing to assume their share with regard to icebreaking, dredging and the setting up of the signals, but they want to do it at the lowest possible cost. |
| There is not sufficient icebreaking capacity to do the job and because of the narrow channels it is very difficult to keep them open as the ice closes in behind the icebreaker very quickly. |
| The Seaway is coordinating closely with the Canadian Coast Guard on setting a date for icebreaking activity in the upper St. Lawrence River. |
| By the 1970s, icebreaking ships were equipped with automatic transmissions of satellite photographs of ice in Antarctica. |
| Six of those vessels are classified as icebreaking ships. |
| The Sir Wilfrid Laurier, an icebreaker, also played a major role in the icebreaking operations on the river. |
