Tibbitt to Contwoyto Winter Road

Tibbitt to Contwoyto Winter Road
The entrance of De Beers' Snap Lake Diamond Mine, NT
Route information
Maintained by Nuna Logistics and RTL-Robinson
Length:	600 km (400 mi) Can be as short as 400 km (250 mi)
Existed:	1982 – present
Major junctions
West end:	Ingraham Trail, Northwest Territories
East end:	Jericho Diamond Mine, Nunavut
Highway system

Tibbitt to Contwoyto Winter Road is an annual ice road first built in 1982 to service mines and exploration activities in the Northwest Territories and Nunavut in Northern Canada. Between 400 and 600 km (250 and 370 mi) long, the road is said to be the world's longest heavy haul ice road and operates for eight to ten weeks starting in the last week of January. Most of the road (85%–87%) is built over frozen lakes, 495 km (308 mi), with the remaining 73 km (45 mi) built on over 64 land portages between lakes. This ice road was the location of the first season of Ice Road Truckers.

The winter road is constructed by Nuna Logistics and RTL-Robinson every January and takes about six weeks to complete. The first vehicle along each season is a Swedish-made Hägglund army-type reconnaissance vehicle designed to float if it falls through the ice; it tows an ice-thickness-detecting sonar. This is followed by road building equipment including "specialized low ground pressure equipment". The road, built extra wide to avoid blockages during blizzards and to allow opposing trucks to pass, is kept clear of snow, which acts as insulation, throughout the season as removal allows the ice to freeze faster and thicker. The road is 50 m (160 ft) wide on the ice, but narrower on land portages ranging between 12 and 15 m (39 and 49 ft) wide. Once initially built, the road is checked by drilling holes into the ice. If the ice needs to be thickened, water trucks are called in to add water to that specific area. The road is only operational during February and March, an average of 67 days per year. The ice has been proven by engineers to support light vehicle loads at 70 cm (28 in) and increasing to full highway truck loads as the ice thickens. A thickness of 107 cm (42 in) is required for a super B tanker carrying up to 50,000 L (11,000 imp gal; 13,000 US gal) and may weigh up to 42 t (41 long tons; 46 short tons).