See also:

Peel River Ferry
 
Old Crow River Ice-free Period
 
Road traffic

Arctic Borderlands Ecological Knowledge Co-op

What is happening?

• This graph shows variation from year to year in the duration of the Peel River ice bridge, but no obvious trend.
• On average the ice bridge opens on November 14th and closes on May 6th. Over the last 30 years the season has averaged 174 days. The longest ice bridge season was the winter of 2004-05 (192 days) and the shortest season was in 1980-81 (150 days).

Why is it happening?

• The variation in ice bridge season is expected to be based primarily on the natural events that determine freeze-up and break-up of the river. However, engineers determine the depth of ice needed for safe travel over the ice bridge and opinions on what ice thickness is safe is likely to have changed several times during the past two decades. This "human factor" may be responsible for some of the variation in opening and closing dates.

Why is it important?

• The timing of spring break-up and winter freeze-up influences many parts of the ecosystem, including movement of wildlife and habitat characteristics of the river. These dates also have an economic impact on people living in the Delta as transportation costs change dramatically when rivers cannot be crossed.

Technical Notes

• The data presented here only go back as far as 1980 although there is limited information for the years 1975-1979. Data provided by Government of Northwest Territories Department of Transportation.
• The dates shown in this graph are based on ice road openings for small vehicles (less than 5 tonnes).