It was decided to evacuate the "Knospe" weather station during the summer of 1942, as the ice-free season made an Allied attack possible.
The short ice-free season made it difficult to take all the posts in one year.
Factors such as prolonged ice-free seasons and increasing water temperatures could have unforeseen effects on the environment.
The ferry is free of tolls and operates between 7:00 am and midnight, during the ice-free season.
The barge has tolls and operates twice per day during the ice-free season while an ice-road is used during part of the winter.
There are no permanent settlements but there are fly-in fish camps where large lake trout can be caught during the 2-month ice-free season.
The ferry operates during the ice-free season; during the winter months the department lays out and maintains an ice road across the lake.
During the ice-free season, the Mackenzie is a major transportation link through the vast wilderness of northern Canada, linking the numerous scattered and isolated communities along its course.
Due to its dependence on water transport, the railroad only operated during the ice-free seasons.
When Fennica entered service in 1993, it was agreed that the multipurpose icebreakers would be chartered for offshore duties about 180 days per year during the ice-free season.