Technical information, news, research, and opinion on avalanches, snow safety, and winter backcountry travel.

Wednesday, February 26, 2014

Washington Terrain Ratings

It's the little things that kill—Bush

DISCLAIMER
TRAVELING IN AVALANCHE TERRAIN MAY RESULT IN SERIOUS INJURY OR DEATH. THESE TERRAIN RATINGS DO NOT CONSIDER CRITICAL FACTORS RELATED TO AVALANCHE FORMATION SUCH AS CURRENT WEATHER OR THE STRUCTURE OR MECHANICAL STABILITY OF THE SNOWPACK. NONE OF THE TERRAIN RATED IN THIS DOCUMENT IS COMPLETELY SAFE FROM AVALANCHES. THESE TERRAIN RATINGS DO NOT CONTAIN ANY INFORMATION ON CURRENT INSTABILITY NOR ANY FORECAST OF FUTURE INSTABILITY. YOU BEAR FULL RESPONSIBILITY FOR THE CONSEQUENCES THAT MAY ARISE FROM YOUR CHOICES.

Terrain Ratings
( AUTHOR'S NOTE: This post was originally written four years ago, but it has been one of my most popular posts, and I thought that it deserved to be featured again. )Most people are familiar with the idea of terrain ratings, but if you are not familiar with the ATES technical model, review the following video:



Introduction
This document contains terrain ratings for ski trips in Washington State. These terrain ratings provide an overall picture of the avalanche exposure for the terrain listed. The author's interpretation of ATES parameters are as follows:
  • The ATES rating system considers avalanche exposure. Other hazards exist.
  • The amount of exposure increases by at least 1 order of magnitude for each rating level.
  • Exposure to avalanche terrain does not increase in a linear manner.
  • Exposure for a simple tour might be viewed as a value of 4.
  • Exposure for a challenging tour is 16.
  • Exposure for a complex tour is 64.
  • In addition many tours have elements of each classification but these ratings are constructed with the entire tour, including the return, in mind.
  • Tours rated challenging are not conservative choices when the danger rating is considerable or higher.
  • Combine these ratings with the current avalanche danger and your personal risk acceptance level.
Simple
Exposure to low 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. Choose these trips when avalanche danger is Considerable or higher.
  1. Aiken Lava Bed
  2. Alpental To Source Lake
  3. Amabilis Mountain
  4. Artist's Point
  5. Clara Lake
  6. Hidden Valley Snoqualmie Pass
  7. Hyak Nordic Trails
  8. Diamond Head Road Ski
  9. Diamond Head Trees
  10. Earl Peak Approach via Bean Creek ( Before Climbing To Earl Pass )
  11. Heather Ridge To Skyline Lake
  12. Icicle Ridge
  13. Marble Mountain
  14. Merritt Lake
  15. Mt. Angeles
  16. Narada Falls To Reflection Lakes ( Avoiding the obvious avalanche slope near the parking lot. )
  17. Narada Falls To Paradise
  18. Olympic National Park Lodge Run
  19. Olympic National Park Toilet Bowl
  20. Olympic National Park Waterhole Trail
  21. Olympic National Park Obstruction Point Ridgeline Tour
  22. Olympic Hot Springs
  23. Paradise to Glacier Vista
  24. Silver Basin Flats ( No travel on steep, open slopes around the basin. )
  25. Stetattle Ridge
Challenging
Exposure to well defined avalanche paths, starting zones or terrain traps; options exist to reduce or eliminate exposure with careful route-finding. Glacier travel is straightforward but crevasse hazards may exist. Choose these trips when avalanche danger is moderate.
  1. Alpental To Ridge Above Snow Lake
  2. Cement Basin
  3. Castle / Pinnacle Saddle
  4. Crystal Lake Basin Forested Slopes
  5. Diamond Head Chutes
  6. Eagle Mountain
  7. Earl Peak Approach via Bean Creek, Including Uphill To Earl Pass
  8. Goat Rocks To Treeline
  9. Governor's Ridge
  10. Heather Ridge Backside
  11. Heather Ridge Moonlight Bowl
  12. Hurricane Ridge
  13. Jim Hill Mountain
  14. Jove Peak Approach
  15. Jove Peak South Face Lower Slopes
  16. Kendall Ridge
  17. Lake Stuart
  18. Lichtenburg Mountain North Side
  19. Marmot Pass, To Treeline
  20. Mazama Back Bowls
  21. Mazama Ridge Ski Slopes
  22. Mission Peak
  23. Mt. Catherine
  24. Mt. Margaret
  25. Mt. Roosevelt
  26. Mt. Tamanos
  27. Naches Peak
  28. Narada Falls to Reflection Lakes ( travel up or down the obvious avalanche slope ).
  29. Norse Peak
  30. Paradise To Cowlitz Rocks
  31. Paradise to Panorama Point or McClure Rock
  32. Paradise To Stevens Canyon Via Road
  33. Peak 7828 approach only.
  34. Phantom Trees ( Up to 600 vertical feet / 200 vertical metres below summit. )
  35. Pickhandle Basin
  36. Skyline Ridge
  37. Silver Basin Lower Slopes ( up to the party knoll )
  38. Tunnel Creek ( South side of Cowboy Mountain, Stevens Pass ).
  39. Wedge Mountain, Travel Confined To Ridges, Forested Slopes
  40. Yakima Peak
  41. Yodelin Trees
Complex
Exposure to multiple overlapping avalanche paths or large expanses of steep, open terrain; multiple avalanche starting zones and terrain traps below; minimal options to reduce exposure. Complicated glacier travel with extensive crevasse bands or icefalls. Choose these trips when avalanche danger is moderate or low.
  1. Alaska Mountain
  2. Bacon Peak
  3. Big Slide Peak Summit & North Face
  4. Burroughs Mountain
  5. Butter Creek Drainage
  6. Boston Basin
  7. Camp Muir to Nisqually Bridge
  8. Cannon Mountain Northwest Face via Avalanche Path and Central Colouir.
  9. Cashmere Mountain Summit
  10. Cashmere Mountain Traverse
  11. Chair Peak Circumnavigation
  12. Chair Peak South Basin
  13. Chickamin Peak
  14. Clark Mountain
  15. Colchuck Peak
  16. Colfax Peak
  17. Cowlitz Chimneys
  18. Crystal Lake Basin Open Slopes
  19. Crystal Mountain To Chinook Pass
  20. Cutthroat Pass
  21. Cutthroat Ridge Descents
  22. Dome Peak
  23. Dragontail Peak
  24. Earl Peak Southwest Face
  25. Earl Peak Southeast Face
  26. Earl Peak North Bowls
  27. Eightmile Mountain
  28. Eldorado Peak
  29. Forbidden Peak
  30. Fuhrer Finger
  31. Glacier Peak
  32. Goat Island Mountain
  33. Goat Pass ( Mt. Stuart Area )
  34. Goat Rocks Alpine
  35. Grindstone Mountain
  36. Heliotrope Ridge
  37. Hidden Lakes Peak
  38. Horseshoe Lake
  39. Jack Ridge
  40. Jove Peak South Face From Summit
  41. Lichtenburg Mountain South Side
  42. Lichtenburg Mountain West Side
  43. Lichtenburg Mountain Summit
  44. Lundin Peak
  45. Marmot Pass, To Saddle
  46. Mt. Adams
  47. Mt. Baker Summit
  48. Mt. Buckner
  49. Mt. Howard Summit
  50. Mt. Olympus
  51. Mt. Mastiff Summit
  52. Mt. Maude
  53. Mt. Rainier Carbon Glacier
  54. Mt. Rainier Sunset Amphitheatre
  55. Mt. Rainier Liberty Ridge
  56. Mt. Rainier Summit
  57. Mt. Rainier Glacier Basin
  58. Mt. Rainier Steamboat Prow
  59. Mt. Saint Helens
  60. Mt. Snoqualmie To Summit
  61. Mt. Ross to Davis Peak Traverse
  62. Mt. Shuksan
  63. Mt. Stuart
  64. Mt. Stuart Sherpa Glacier
  65. Mt. Terror
  66. Mt. Triumph
  67. Olympic National Park Klahane Ridge
  68. Paradise to Camp Muir
  69. Peak 7828 To Summit
  70. Ptarmigan Traverse
  71. Pyramid Peak
  72. Red Mountain
  73. Reflection Lakes To Castle Peak
  74. Reflection Lakes To Pinnacle Peak
  75. Rock-Howard-Mastiff Mountain Traverse
  76. Rock Mountain Summit
  77. Ruby Mountain
  78. Sahale Arm
  79. Sarvant Glaciers
  80. Silver Basin Upper Slopes ( to ridgeline or summit of Silver King )
  81. Silver Star Mountain
  82. Sinister Peak
  83. Skidgravel Peak
  84. Slot Couloir
  85. Sylvester Lake
  86. Tatoosh Range Traverse
  87. Table Mountain
  88. Three Fingers Mountain
  89. Tower Mountain Northeast Couloir
  90. Unicorn Peak
  91. Union Creek
  92. Van Trump Park
  93. Vesper Peak
  94. Wedge Mountain, ( Any Travel On East Face )
  95. Whitehorse Mountain
Credits

2 comments:

  1. Wow, this is a great list and a great way to think about approaching terrain and replanning for danger levels. Thanks!

    ReplyDelete
  2. Thanks for the kind words. Please share these with your friends.

    Most of the credit goes to the Canadian Avalanche Centre and ParksCanada, who designed the ATES rating system, and the methodology behind choosing terrain by danger level.

    I just contributed the terrain ratings.

    ReplyDelete