Avalanche Terrain Exposure Scale

The Avalanche Terrain Exposure Scale (ATES) is used in conjunction with the CAC Avaluator tool for trip planning.

Avalanche Terrain Exposure Scale (ATES) v.1/04

Description	Class	Terrain Criteria
Simple	1	Exposure to long angle or primarily forested terrain. Some forest openings may involve the runout zones of infrequent avalanches. Many options to reduce or eliminate exposure. No glacier travel.
Challenging	2	Exposure to well defined avalanche paths, starting zones or terrain traps; options exist to reduce or eliminate exposure with careful routefinding. Glacier travel is straightforward but crevasse hazard may exist.
Complex	3	Exposure to multiple overlapping avalanche paths or large expanses of steep, open terrain; multiple avalanche starting zones or terrain traps below; minial options to reduce exposure. Complicated glacier travel with extensive crevasse bands or icefalls.

The detailed technical criteria for Simple, Challenging and Complex ratings are available from the Parks Canada website.

ATES Terrain Ratings for SW BC Destinations

Official CAA ATES ratings are set by avalanche professionals who are memebers of the Canadian Avalanche Association. VOC ATES ratings are suggested by VOC members for interim use until CAA avalanche professional rates these trips.

Avalanche Terrain Exposure Scale:

Trip	Description	CAA ATES Rating[1]	VOC ATES Rating
Mount Seymour to Brocton Point	Ski area parking lot to Brocton Point via BC Parks Trail	Simple
Mount Seymour to 1st Peak	Ski area parking lot to First Peak via BC Parks Trail	Challenging
Mount Seymour to 3rd Peak	Ski area parking lot to Third Peak via BC Parks Trail	Complex
Mount Elsay		Complex
Holyburn Mountain		Simple
Mount Strachan		Complex
Mt. Harvey	From Harvey Creek	Challenging
Ben Lomond	NW Ridge	Complex
Meslillooet Mountain	E Ridge	Complex
Mamquam Mountain	NW Ridge	Complex
Diamond Head: Elfin Lakes Shelter	From Diamond Head parking lot along the marked route on the top of Paul Ridge to the Elfin Lakes Shelter	Simple
Diamond Head: Paul Ridge	Yoyo skiing on the north side of the ridge		Challenging
Garibaldi Neve Traverse	Normal low route from Elfin Lakes Shelter to Garibaldi Lake	Challenging
Mount Garibaldi	NE Face	Complex
Garibaldi Lake Trail (to Burton Hut)	Normal route to the Burton Hut via Rubble Creek Trail and skiing across Garibaldi Lake. Entire route is below treeline.	Simple
Black Tusk	Approach from Garibaldi lake or microwave towers. Objective is skiing slopes just below final rock summit	Complex
Black Tusk East Knob	Approach from Garibaldi Lake with objective of skiing terrain above Black Tusk Meadows up as high as the summit of the east knob		Challenging
Panorama Ridge		Challenging
Guard Glacier	The long ski run from near the top of the Deception Pinnacles down to the Burton Hut	Challenging
Bookworms via Sphinx Glacier		Challenging
Roe Creek to Brew Hut	Access via Roe Creek road and marked trail to Brew Lake. Main hazard comes from crossing a number of open rocky slopes along the trail that are below treeline. These slopes face south and are known to release wet loose snow avalanches with solar heating. Above Brew Lake there are many route finding options and the best route has very little avalanche exposure, however visibility is frequently poor in this area making hazard identification difficult. See Roe Creek Ski Route page.	Challenging
Brew Lake Basin	Most terrain is low angle but there are a few small steeper slopes to watch out for	Challenging
Bowl and Shady Trees East of Brew Hut	Upper bowl has alpine exposure to winds, treeline below the lake down to 1300m		Challenging
Brandywine Bowl near Brew Hut	This is the bowl immediately below the Brew Hut on the Brandywine Creek side. There are a number of steep couloirs that cause frequent avalanches into this bowl.		Complex
Singing Pass Area	Includes Musical Bumps (Flute, Oboe), Singing Pass, Cowboy Ridge and Russet Ridge	Challenging
Mt Whirlwind		Challenging
Mt Fissile		Complex
Spearhead Traverse		Complex
Blackcomb Peak		Complex
Corona		Complex
Husume		Complex
Mt Decker		Complex
Mt Phalanx & Poop Chutes		Complex
Rainbow Mountain		Challenging
Beverley Creek	Whistler Olympic Park to pass with 21 Mile Creek. Keep to climbers left side	Challenging
Whistler Olympic Park to Hanging Lake		Challenging
Mount Sproatt	via hanging valley from 21 mile creek	Challenging
Wedge Mountain	Any Route	Complex
Wedge-Curie Traverse		Complex
North Joffre Creek	Horseshoe route around north Joffre Creek. The main hazards on this route are the large convex slope NE of Saxifrage, and steep slopes going up and over the shoulder of Cirque Peak.	Complex
Joffre Lakes		Challenging
Cayoosh Mtn		Complex
Cerise Creek to Keith's Hut	Normal route up valley bottom is exposed to several large avalanche paths and a terrain trap (Cerise Creek).	Challenging
Vantage Peak	From Keith's Hut via SW ridge	Challenging
Anniversary Glacier	Keith's Hut to Matier - Joffre col. Exposed traverse beneath SE Face of Joffre Peak to gain the Anniversary Glacier is the crux of the route	Complex
Wendy Thompson Hut access	Normal route from Duffey Lake road via Cayoosh Creek.	Challenging
Mount Rohr		Challenging
Steep Creek		Complex
Van Horlick		Complex
Hurley Silver Mine		Complex
Brian Waddington Hut access	Normal access route via Phelix Creek. This route is below treeline, but crosses a number of large avalanche tracks and runout zones near the valley bottom		Simple
Cabin Hill	Popular skiing area near Brian Waddington Hut.		Challenging
Cabin Hill back side	East facing bowl behind cabin hill		Challenging
Cabin Hill west	ski runs descending NW from the ridge behind cabin hill. These slopes have complex gullies and seem to be more wind affected than surrounding areas		Complex
Mount Gandalf	from Brian Waddington Hut via South Face. This is a large open face with numerous avalanche gullies		Complex
Mount Aragorn	from Brian Waddington Hut via Aragorn Glacier		Challenging
Copp Creek	A long ski run from the Brian Waddington Hut accessed via the Aragorn Glacier		Complex
Return of the King	A steep ski run coming off the subsidiary ridge north of Peregrine Peak and ending at the Brian Waddington Hut. This run is often used to return to the hut from the skiing areas around the upper lake.		Complex
Peregrine Bowl	The bowl the leads into the col west of Peregrine Peak		Challenging
Back side of Peregrine col	The steep run on the south side of the col west of Peregrine Peak		Challenging
Gandalf Col	The bowl below the col south of Gandalf Peak. Exposure to large avalanche slopes from north facing slopes on the summit between the gandalf col and the peregrine col.		Challenging
Needle Peak Bowl		Challenging
Zoa Peak		Challenging
Thar Basin		Complex

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