Avalanche Cycle and Avalanche Control Yoho National Park

<p>Parks Canada Visitor Safety observed evidence of a natural cycle today in Yoho National Park as we arrived to conduct avalanche control work on Mt Dennis. Visibility remained poor all day due to valley fog although we were able to come and go through the fog at different times on our flights. Avalanches had run into all three fans on Mt Field however these were relatively small slabs in the scope of what w remains above Silk Tassel etc. No control work was conducted on Mt Field. Large slabs from the alpine on Mt Dennis had filled the fans of Pilsner Pillar and Heineken Hall, control work added to these piles however we do not think we hit Carlsberg/ Kroneburg. A shot was placed on Guiness Stout and the resulting avalanche buried the road 3m deep. The Guiness descent gully remains un-touched. CP / Parks Canada also conducted control work on Mt Stephen. High targets above Twisted resulted in some slab activity on the approach slopes and hit the tracks. 2 shots were placed in the Home Brew gully. Results hit the tracks but there are untouched targets higher up that could not be reached. Nothing had run or was controlled on Super Bock. Cougar and Cool Spring and Massey's (see earlier post) have all run into the fans but the start zones were obscured. On a pass by the north side of Burgess Pass/ Wallcot Peak we saw extensive slab activity in glades below treeline with a few notable examples of the December 2 crust evident in the bed surfaces. 2 of the 3 Burgess road paths above the Emerald Lake Road had run full path. </p>