Destruction Bay to Beaver Creek is just over 100 miles. We plan four hours for the drive, not including our lunch stops and doggy pee stops.
Last spring there were a couple of very serious dips between Whitehorse and our place, about half way to Haines Junction on the AK Hwy. These dips weren't marked either. Towing the fifth wheel, we went over them at about 20 mph so the fiver's rear bumper wouldn't hit bottom. My car was okay going over them at 60 mph but DH's vehicle needed a slow down to about 40 mph or he'd bottom out.
Spring 2012 the Alaska Highway was closed for 4 days at Rancheria due to a bridge wash out. The Cassiar Highway closed at the same time. As did the Campbell Highway. The AK Hwy near Kluane Lake also had some washouts/mudslides that closed the highway for two days. All at the same time. Folks in Whitehorse weren't going anywhere and no one was getting to Whitehorse. Snowpack had been very high through the winter and then it warmed suddenly and the water flows were tremendous. So always be prepared to drycamp/boondock for a few days in case you hit one of these blockages.
This winter we have a LOT of snow. If it melts gradually, great. If it is a cold and late spring again, as it was in 2013, we could again be in trouble. There were several washouts in the area in spring 2013. The highway crews are amazing and get things moving as quickly as possible BUT there's only so much they can do when Old Man Winter won't leave Mother Nature alone.