Ice caves are spectacular natural attractions, but they鈥檙e not exactly known for being safe places to hang out. These caverns are, after all, formed by melting, shifting swaths of snow and ice that can collapse or crumble without warning. 鈥淒eceivingly friendly鈥 is how Seattle-based Mount Everest guide David Morton describes them.
On Monday, hikers at the Big Four Ice Caves in Washington found out just how volatile these environments can be, and with tragic results. A major collapse in one of the caves left a 34-year-old woman dead and five people injured, including two children and one man in critical condition. Those people, and several others, entered the caves despite warning signs outside.聽The cause of the collapse can largely be chocked up to unseasonably warm temperatures that has destabilized the caves. 鈥淲e鈥檙e looking at conditions that we usually don鈥檛 see until September,鈥 says Aleta Eng, partnership specialist for Mt. Baker-Snoqualmie National Forest.
Warm weather notwithstanding, these caves are dangerous.聽This isn鈥檛 the first time there鈥檚 been an accident at the Big Four. In 2010, 11-year-old Grace Tam was killed by a boulder of falling ice just outside the聽caves. Now, a 聽commemorating Tam鈥檚 life鈥攁nd warning others of the dangers鈥攊s posted right outside the caves. Other signs on the one-mile trail to the caves also warn of falling ice and instruct people not to get too close to the caves, much less enter them. On the same day the accident happened, 聽went live on YouTube showing another collapse at the very front of the caves.
鈥淲hen you鈥檙e trying to figure out if an area is safe, you have to look at the history,鈥 says Gordon Janow, Director of Operations for , a mountain guide service in the Seattle area. 鈥淚t鈥檚 clear that these caves are unsafe because there鈥檚 a record of bad events here.鈥
It takes years of experience with snow and ice environments to evaluate the stability of a specific ice cave, Morton says. These features are delicate, and only form within a rare nexus of conditions. The caves at Big Four form when聽running water from the mountain above tunnels through a snowfield at its base.
In winter and spring, avalanches shoot down the north face of Big Four Mountain, creating a snowfield at the bottom. As the area melts out in warmer months, water runs down off the mountain and drills through the snow, creating the caves visitors travel from hundreds of miles around to hike through. Thousands of visitors flock to the caves during summer, Eng says.
The saddest part of Monday鈥檚 tragedy may be that it was preventable.聽Now, some in the outdoor industry say that aggressive measures need to be taken to keep people from accessing the caves at all. 鈥淚 think we need to just put up a fence around it and keep people out. People don鈥檛 read signs,鈥 said Jason Martin, Director of Operations for the , another Northwest guide service. 鈥淚t鈥檚 just way too easy to get to the caves via the trail right now, and people get hurt.鈥
For now, it appears the U.S. Forest Service is heeding the message. It has closed off access to the Big Four Ice Caves at one-third of a mile down the trail. Whether the caves will ever be reopened is unclear.