And we also build ice bridges across rivers and some lakes (Lake Williston, a very large man-made lake in central British Columbia) that are capable of 'floating' a 100 ton logging truck. The bridges follow the same construction principle, except that the sides are made of bundled logs so that a depth of water (ice) can be established. The river bridges are generally only a few hundred feet long, but the one that used to be on Lake Willistion spanned a few miles. The trucks would always be climbing up hill when they crossed, as the portion that they were on was in essence sinking lower than the 'resting' level of the road. Scary!! But it was used for about 20 years before an all-weather road was built around the lake. Of course, you need real cold weather to keep these things in operation - generally the winter temperatures are -20C, dropping to as low as -40C in mid winter. No good for kayaking, so you might as well log!!

: In the very north of BC most of the timber harvesting is done during the
: winter when the ground is frozen. In fact many of the roads are "ice
: roads" built on top of muskeg. These are built similar to an outdoor
: hockey rink with water pumps feeding water from nearby creeks. These
: freeze very quickly allowing fully loaded logging trucks to operate for ~4
: months of the year.

: One benefit is that in the summer these are virtually impassable by vehicle.

: And in any season they make for lousy kayaking!

: grant