SQUAMISH 鈥� Crews have built an emergency bridge to give safe passage to hundreds of campers stranded by a road washout near Squamish.
About 250 people had been stuck after heavy rains several days ago stirred a torrent of mud and water over the weekend, rendering the Squamish Valley Forest Service Road impassable.
Ministry spokeswoman Vivian Thomas says access to the area cut off by the slide was restored Monday afternoon.
"The work going better than planned because it is sunny today," said Vivian Thomas.
Many people on the wrong side of the road had pitched tents for a music festival.
They had been asked by authorities to share food and supplies while waiting for an impromptu roadway to be secured.
Police, search and rescue personnel, and staff from the provincial forests ministry were keeping an eye on the scene.
There were no reports of injuries.
The Squamish Valley has a long history of rock, mud, and debris flows associated with past volcanic activity.
In June 1984, an estimated 3.2 million cubic metres of volcanic debris travelled two kilometres down Avalanche Creek on Mount Cayley to dam the confluence of Avalanche and Turbid creeks.
The breaking of the dam "caused super-elevations, hurled rocks and wood through the air, uprooted trees, and spattered mud 16 metres up trees," according to a 1992 report on the event.
"The debris flow removed the logging road bridge and road approaches at the mouth of Turbid Creek, blocked the Squamish River during surges, and introduced huge quantities of sediment to the Squamish River."
Another report, dated 1991 and involving radiocarbon dating of tree fragments, found evidence of at least three major debris avalanches initiated by the collapse of the western flank of Mount Cayley, including 4,800, 1,100 and 500 years earlier.
"All three debris avalanches dammed the Squamish River and formed temporary lakes upstream of the debris," the report concluded. "Debris avalanches from Mount Cayley and the effects of a possible damming of the Squamish River are major geomorphic hazards to public safety and economic development in the Squash Valley."
