How long is the Mackenzie River navigation season?

Due to the cool climate of the Mackenzie Lowlands, navigation on the Mackenzie River system is limited to approximately four months per year.1

The river's seasonal accessibility is heavily influenced by ice conditions. While the ice begins to break up in the southern sections in early to mid-May, the Great Slave Lake—the river's source—is the last part of the waterway to clear, sometimes retaining ice until mid-June. During the late summer, shallow water and shifting sandbars can also present challenges for the shallow-draft barges and tugs that utilize the river for transportation.234