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Why a Canadian Road Holds Loaded Trucks to 25 km/h on Its Frozen Lakes, Source & Pace (The WEDGE Method LLC).

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Why a Canadian Road Holds Loaded Trucks to 25 km/h on Its Frozen Lakes on YouTube

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  1. 0:00 “On the 9th of February 2015, two radar satellites of the German TanDEM-X mission passed over a frozen lake in Canada's Northwest Territories.” [c01.00, sourced]
  2. 0:10 “They imaged the same ice twice, ten seconds apart.” [c01.01, sourced]
  3. 0:16 “Processed together, the two images show how far the ice surface moved up or down between them.” [c01.02, sourced]
  4. 0:23 “Across the lake ran a road. And around one truck on it, the ice had formed a pattern of waves.” [c01.03, sourced]
  5. 0:30 “The researchers modelled the ice there as more than a metre thick.” [c01.04, sourced]
  6. 0:34 “So why would ice that thick ripple like water?” [c01.05, framing (no factual claim)]
  7. 0:39 “The answer helps explain why this road has a speed limit as well as a weight limit.” [c01.06, framing (no factual claim)]
  8. 0:50 “It's called the Tibbitt to Contwoyto Winter Road. It starts at Tibbitt Lake, where Highway 4 ends, east of Yellowknife.” [c02.00, sourced]
  9. 0:58 “From there it runs north for about 400 kilometres, and about 85 per cent of it is built over frozen lakes.” [c02.01, sourced]
  10. 1:05 “The rest, the joint venture says, crosses land between the lakes, on stretches called portages.” [c02.02, as reported]
  11. 1:11 “According to CBC News, it connects to three diamond mines northeast of Yellowknife: Diavik, Ekati and Gahcho Kué.” [c02.03, as reported]
  12. 1:19 “No other highway reached that region, researchers wrote in 2016. For ten months of the year, it was only accessible by air.” [c02.04, sourced]
  13. 1:28 “So the heavy supplies come in over the ice. Diesel fuel is one of the main loads.” [c02.05, sourced]
  14. 1:33 “The same paper puts the trucks' gross weights at up to 40 tonnes, and sometimes more.” [c02.06, sourced]
  15. 1:39 “In the joint venture's figures for 2007 to 2020, the busiest season was 2007, when 10,922 truckloads went north.” [c02.07, sourced]
  16. 1:49 “And because most of it sits on ice, the joint venture that runs it says, the road must be rebuilt for every season.” [c02.08, as reported]
  17. 1:56 “Construction normally starts in mid-December, it says, aiming to open around the 1st of February.” [c02.09, as reported]
  18. 2:05 “A big part of building it is dealing with snow.” [c03.00, framing (no factual claim)]
  19. 2:08 “Snow on lake ice acts like a blanket. A 2017 study notes that heavier snowfall slows the thickening of lake ice by insulating it.” [c03.01, sourced]
  20. 2:17 “So crews remove the snow, and flood the ice with water to build it thicker and repair damage.” [c03.02, sourced]
  21. 2:23 “Built with sound practice, once completely frozen and inspected, the Northwest Territories' ice guide says flooded ice can be considered as having similar strength to natural ice.” [c03.03, sourced]
  22. 2:34 “The territory's guide names ground-penetrating radar as its primary method for measuring the thickness.” [c03.04, sourced]
  23. 2:40 “On the territory's lake roads, when radar is used, it asks for at least one reading every half metre along each survey line.” [c03.05, sourced]
  24. 2:47 “For routine operations, the territory's guide then estimates the allowed load with Gold's formula: P equals A times h squared.” [c03.06, sourced]
  25. 2:56 “h is the minimum thickness of good-quality ice, in centimetres. P is the allowed gross vehicle weight, in kilograms.” [c03.07, sourced]
  26. 3:03 “And A depends on the operating level, which sets how much testing and control the road needs.” [c03.08, sourced]
  27. 3:09 “For routine operations on a lake road, the territory's guide uses an A of 4.” [c03.09, sourced]
  28. 3:13 “With the same A, twice the ice gives four times the allowed weight.” [c03.10, sourced]
  29. 3:18 “In the guide's own table, 50 centimetres of ice allows 10,000 kilograms. 100 centimetres allows 40,000.” [c03.11, sourced]
  30. 3:27 “On the Tibbitt to Contwoyto road, the joint venture says, the road opens at a minimum of 29 inches of ice, about 74 centimetres, and reaches full load capacity at 39 inches, about 99.” [c03.12, as reported]
  31. 3:40 “That's the weight rule. Speed brings a different kind of stress.” [c03.15, framing (no factual claim)]
  32. 3:47 “Lake ice floats because it is 8 to 10 per cent less dense than water.” [c04.00, sourced]
  33. 3:53 “It may look rigid, but under a load it bends.” [c04.01, sourced]
  34. 3:57 “The dip under the load is called the deflection bowl.” [c04.02, sourced]
  35. 4:00 “Under the load, bending puts the bottom of the ice in tension. If that stress passes the ice's strength, it cracks.” [c04.03, sourced]
  36. 4:08 “Next, set the truck moving. The bowl travels with it, at the truck's speed.” [c04.04, sourced]
  37. 4:13 “As the truck speeds up toward a certain speed, the bowl gets deeper and narrower. In Takizawa's field tests, its lowest point lagged behind the load.” [c04.05, sourced]
  38. 4:23 “At that speed, the guide says, the bowl reaches its deepest and the bending stress its highest. It's called the critical speed.” [c04.06, sourced]
  39. 4:31 “The guide says a series of waves is trapped underneath the vehicle. In the theory, wave energy travels at the truck's own speed, so it can't escape, and builds up.” [c04.07, sourced]
  40. 4:42 “Theoretical studies show the stresses can be 50 per cent higher than below the critical speed.” [c04.08, sourced]
  41. 4:47 “Floating ice and the water under it carry waves of their own, and in the theory, their crests have a slowest possible speed.” [c04.09, sourced]
  42. 4:55 “Below that speed, a truck still bends the ice, but no steady wave can keep pace with it. That slowest wave speed is the critical speed.” [c04.10, sourced]
  43. 5:04 “In February 1981, on the sea ice of Lake Saroma in Hokkaido, Japan, Takatoshi Takizawa tested it with a snowmobile.” [c04.11, sourced]
  44. 5:13 “The ice was 17 to 18 centimetres thick, over 6.8 metres of water. He made 141 test runs, at up to 14.2 metres a second.” [c04.12, sourced]
  45. 5:24 “The deflection was amplified most at an estimated 5.8 metres a second, just under 21 kilometres an hour.” [c04.13, sourced]
  46. 5:31 “Just above that speed, two waves appeared: a shorter one ahead of the snowmobile, and a longer one behind it.” [c04.14, sourced]
  47. 5:41 “The critical speed depends on the ice's thickness and stiffness, and on the depth of the water under it. A 2022 study calls the depth the most important factor.” [c05.00, sourced]
  48. 5:52 “Over very deep water, the guide says, it's usually higher than a typical vehicle speed. As the water gets shallow near a shore, it drops.” [c05.01, sourced]
  49. 6:01 “In the right conditions, a 2022 study says, it can fall as low as 10 kilometres an hour.” [c05.02, sourced]
  50. 6:08 “Near shore, the waves can also reflect off the land, back toward the truck. The guide says reflected waves are strongest when the road meets the shore at a right angle.” [c05.03, sourced]
  51. 6:18 “So where possible, the guide recommends approaches built to meet the shore at 45 degrees.” [c05.04, sourced]
  52. 6:24 “Near the shore, a 2022 study says, waves from heavy vehicles can add up until the pressure blows a hole in the ice. Researchers call it a blowout.” [c05.05, sourced]
  53. 6:33 “When trucks pass close together, their bowls can overlap. So when loaded trucks meet on a lake, both slow to 10 kilometres an hour.” [c05.06, sourced]
  54. 6:42 “The guide also has heavy trucks going the same way keep 500 metres apart. A 2016 paper describes the same 500-metre rule on the Tibbitt to Contwoyto road.” [c05.07, sourced]
  55. 6:53 “And the speed limit. In the joint venture's rules for 2026, unless posted otherwise, a loaded truck on a lake may do 25 kilometres an hour.” [c05.08, sourced]
  56. 7:02 “An empty truck may do 40, those rules say. Pickups and service vehicles rated three tons or less, up to 90.” [c05.10, as reported]
  57. 7:09 “Those are the rules. Satellites gave researchers a way to compare the ice's real movement with the theory.” [c05.11, sourced]
  58. 7:19 “Gordon Lake is one of the larger lakes on the route: up to 45 kilometres long.” [c06.00, sourced]
  59. 7:24 “Researchers from the National Research Council of Canada and Natural Resources Canada compared the satellite data with the theory.” [c06.01, sourced]
  60. 7:31 “For the 10th of February, they studied a truck heading north, modelled as a heavy one, at an estimated 7 metres a second: about 25 kilometres an hour.” [c06.02, sourced]
  61. 7:41 “The critical speed they calculated there was over 12 metres a second. And the satellite showed no wave pattern, just as the theory predicted.” [c06.03, sourced]
  62. 7:49 “For the 9th, a truck heading south, modelled as an unloaded one, at an estimated 16 metres a second: almost 58 kilometres an hour.” [c06.04, sourced]
  63. 7:58 “For the ice values they tried, the critical speed there was 14.51 metres a second or lower. The truck was above it.” [c06.05, sourced]
  64. 8:06 “At the time, the paper noted, empty trucks could be allowed up to 60 kilometres an hour.” [c06.06, sourced]
  65. 8:11 “This time the satellite data showed waves, the pattern the theory predicted for a truck above the critical speed.” [c06.07, sourced]
  66. 8:18 “Along the road, the waves were clearer ahead of the truck. Behind it, the ice was less disturbed, which supports what the theory calls a shadow zone.” [c06.08, sourced]
  67. 8:27 “From these cases, the authors wrote that southbound vehicles on the road seemed to be exceeding the critical speed.” [c06.09, sourced]
  68. 8:34 “Their preliminary results also suggested the stresses fade out about 100 metres from a truck, so the 500-metre spacing could be reassessed, if ice strength is what sets it.” [c06.10, sourced]
  69. 8:44 “The wave was real, and it could be measured from orbit.” [c06.12, framing (no factual claim)]
  70. 8:51 “The road also needs ice that is thick enough, for long enough.” [c07.00, framing (no factual claim)]
  71. 8:55 “In the winter of 2005 to 2006, the 2017 study reports, mild and stormy weather substantially shortened the season.” [c07.01, sourced]
  72. 9:04 “The road shut early on thin ice. The study counts about 1,200 loads that had to be flown to the mines instead, later that year.” [c07.02, sourced]
  73. 9:13 “Its table, taken from joint-venture records, has the road open 80 days in 2002 and 58 in 2012. The joint venture's own 2021 poster lists 53 for 2012.” [c07.03, as reported]
  74. 9:27 “The study notes the mines' changing needs move the season too. Climate is another reason.” [c07.04, sourced]
  75. 9:33 “Its climate projections point to thinner lake ice, and a shorter window when the ice is thick enough for trucks.” [c07.05, sourced]
  76. 9:39 “The authors warn the size of that change is uncertain. The direction, they say, is more certain.” [c07.06, sourced]
  77. 9:45 “Traffic has fallen too. After 10,922 northbound loads in 2007, the joint venture counted about 3,200 in the 2025 to 2026 season.” [c07.07, as reported]
  78. 9:59 “Then came a different threat: the mines' own needs.” [c07.08, framing (no factual claim)]
  79. 10:06 “In September 2026, the joint venture said it is not planning a winter road program in 2027.” [c08.00, sourced]
  80. 10:13 “According to CBC News, it would be the first time since the road first opened in 1982.” [c08.01, as reported]
  81. 10:18 “The Diavik mine ended production, as planned, in March 2026. That July, a court order placed the Ekati mine into receivership.” [c08.02, sourced]
  82. 10:29 “And Gahcho Kué has serious financial problems, CBC News reports, with its planned closure moved up from 2031 to 2028.” [c08.03, as reported]
  83. 10:38 “The joint venture says it could restart planning if needs change. Meanwhile, it says, the camps along the road will be placed into care and maintenance.” [c08.04, as reported]
  84. 10:47 “Officials have said in the past, Cabin Radio reports, that building the road costs 20 million Canadian dollars or more a year.” [c08.05, as reported]
  85. 10:54 “Indigenous-owned contractors have helped build and serve the road. Marc Whitford, president of the North Slave Métis Alliance, said, according to CBC News, that if it doesn't open, it's "going to be another kick in the head" for Indigenous corporations.” [c08.06, as reported]
  86. 11:08 “Planning, the joint venture says, is expected to resume for the 2028 season. Diavik says it expects to use the road that year, for its closure work.” [c08.07, as reported]
  87. 11:18 “So, according to the joint venture's plans, in the winter of 2026 to 2027 these lakes may freeze without the mine road built across them.” [c08.08, as reported]
  88. 11:29 “Floating ice will still bend under a load. The physics doesn't take a winter off.” [c08.09, framing (no factual claim)]

Sources

Corrections are listed with their time stamp under CORRECTIONS in the video's description; a correction that changes what the video claims also goes at the top of the description and in the pinned comment.