Editor’s note: This is Rick’s abbreviated summary of Haneda et al.’s (2010, pp. 7-96) in-depth analysis and record of the disaster (published in Japanese, 2012 new edition here). Photos used to illustrate the summary are from the Daisetsuzan Range, but not associated with the disaster. A full report of the incident was also prepared by The Japan Mountain Guides Association (日本山岳ガイド協会), and is available on the web here (PDF in Japanese).
On 13 July 2009 the members of a tour group organized by the Tokyo adventure tourism company Amuse Travel (Amyuuzu Toraberu in Japanese) gathered in the lobby of Shin-Chitose Airport in Hokkaido. The 15 clients and three guides were to undertake a three day trek along the spine of the rugged Daisetsusan mountain range that rises to a number of peaks over 2000m in the centre of the island. Included in the itinerary were two mountains on the ‘100 Famous Peaks’ (hyakumeizan) list that has fuelled a massive boom in mountain walking among Japan’s senior citizens in the last twenty years.
The average age of the ten female and five male clients was 64, and most of them were well into their hyakumeizan campaigns. All had taken up or restarted mountain walking in their later years and most were repeat clients with Amuse or had been on similar organized mountain adventure tours. They were reasonably well equipped and carried three days supply of food. Of the three guides, who were meeting for the first time that day, the 61 year-old tour leader was a qualified mountain guide while the other two had experience of guiding for Amuse or other companies, but only one of them actually had firsthand knowledge of the intended route.
The weather forecast was for a low pressure system to pass over Hokkaido in the next couple of days, so the guides warned the clients to expect deteriorating conditions on their second and third days on the mountain. The first day’s (14 July) weather was fine and the group made good progress over the summit of Asahidake (2291m) to the first hut.
The second day it was raining, but visibility remained fair and the group reached the second hut in the early afternoon without incident. A number of the party, however, had managed to get wet from a combination of the rain, wet trails and overhanging vegetation despite having generally good equipment. The second hut was crowded and cramped, with no space to dry wet gear; some of the clients kept their wet clothes on in an attempt to dry them out. During the night the weather deteriorated further.
July 16 greeted the party with ferocious winds and squalls of rain. Nevertheless, the group set off from the hut at 5.30am into the teeth of the gale. The route from the hut to the summit of Mt. Tomuraushi (2141m) involves about 300m of ascent over 4km, mostly along a broadly defined ridge. In good conditions it should take about two and a half hours. After ascending a short snowfield where some of the clients had to be assisted in putting on their instep crampons, the group reached the main ridge and turned south towards the summit.
Here they encountered extremely strong winds from the west blowing at 20m/second accompanied by rain squalls. Progress along the broad and easy angled ridge became very slow and difficult, with clients repeatedly being blown off the path or off their feet, or having to crouch down in the face of the stronger gusts. In places there were fields of large boulders to be negotiated.
By the time the group reached Kitanuma, a small tarn on the shoulder of the mountain where the summit path branches off, some five hours had passed. A number of clients were beginning to display symptoms of hypothermia, one female client in particular unable to walk unaided and needing to be supported by a guide.
Further time was lost here fording the outflow of the tarn, which had turned into a 2m wide torrent. The guides helped most of the clients across one by one, while the others waited in an extremely exposed position in the full force of the wind. Yet more time was spent waiting while the guides attempted, unsuccessfully, to revive the female client. Finally, after one of the clients voiced concern, the guides conferred and the tour leader decided to bivouac on the spot with the unconscious client while the rest of the party would continue on the traverse path around the summit to the descent route. The guide and the client had an emergency shelter, but both perished from hypothermia within a few hours.
Once alerted, the Mountain Rescue (a specialist police unit in Japan) and the Japan Air Self-Defense Force attempted helicopter flights but conditions were too bad. Only five members finally made it down to the lodge at the foot of the mountain at around midnight to find the Mountain Rescue teams fully mobilized. During the night the weather improved dramatically and in the early hours of the following morning the surviving clients and guides were rescued by helicopter.
Aftermath Notes (by Rick)
In the aftermath of the incident Amuse Travel was placed under police investigation and forced to suspend operations for nearly two months by the Japan Tourism Agency; it would eventually cease trading altogether after another incident in 2012 in which clients lost their lives. The disaster was the worst in a series of similar incidents involving senior citizens on guided mountain tours and prompted Japan’s adventure tourism industry to review guidelines, safety, guiding qualifications and risk management procedures. Although the immediate cause of death on Tomuraushi was hypothermia, it was clear that poor planning and decision making had played a central role. In particular, the pressure on the guides to keep to the schedule to avoid accommodation and flight cancellations was a major factor in their decision to press on in horrendous conditions. In March 2018, the police finally dropped charges of professional negligence against the company president and the surviving guides.
NOTE: Locations are approximate