Kluane Lake presented the soldiers of the 18th with a bridge problem that ingenuity alone would not solve. Fifty miles of their road to Alaska would run along the shore of Kluane Lake. Not a problem. But they had to get themselves and their equipment around the end of Kluane Lake before they could start building road up its far shore.
Slims River flowed down from the Kaskawulsh Glacier and into the southern end of Kluane. Glacial rivers bring debris down the face of the glacier and spread it in a great fan. Over centuries miles of mud, quicksand and unstable debris had accumulated around the end of the lake—between it and the glacier. The soldiers had to bridge Slims River itself, but before they could do that, they had to get a road over those miles.
Through most of July everything going to the other side of Kluane had to go across the lake on a raft. Rules decreed that soldiers couldn’t ride on the raft with the equipment. They rode in the tow launch. But carrying a twenty-three-ton bulldozer, a pontoon raft had little freeboard, rode extremely low in the water, and pulled the stern of the tow launch almost as deep. Given the slightest turbulence, water flooded into both vessels.
Today eight miles of road carries vehicles along the southern shore of Kluane Lake to the Slims River. The 18th struggled throughout July to build that eight miles of road and the 1044-foot-long Slims River Bridge over permafrost and mud. Even in July the bottom of Slims River consists of frozen gravel and dirt. To drive piles into the frozen river bottom, the engineers pressurized water and blasted the bottom to thaw and soften it.
As they worked in the frigid water, it flowed past them at six miles an hour. And its depth changed constantly, ten inches on an average day, eighteen inches on a particularly difficult day.
