Thursday 15 May 2008

Toyako Onsen

With less than 2 weeks to go (I can't quite believe it) my time in Hokkaido is drawing to a close. I wish I could spend longer here, but the limitations of public transport really restrict what you can do.

Anyway, before I leave here there is time to see one last volcano. I knew I wanted to head to the Toyako Onsen area, but I had no idea quite how interesting it would be, and how nice the area would be, too.

Toyako Onsen is, as the name suggests, an onsen (hot spring) resort area. Why does it have so many onsen? Because it is right next to an active volcano. It doesn't even have the good fortune, like Kagoshima and Sakurajima, to be across a stretch of water - the town of Toyako Onsen is right at the foot of the mountain.

Om the other side of the town is Lake Toya, a classic caldera lake (the 3rd largest in Japan, apparently) with a small cluster of extinct volcanic peaks in the centre. In the background you can see another perfect cinder-cone known locally as Hokkaido's Fuji (the shape is almost the same perfect cone).


The view across Lake Toya.

As you can see, when I arrived, the weather was great. It didn't hold. The one day I had to explore the area, it rained. A lot. Ah well.

The volcano next to the town is called Mt. Usu (Usuzan). It's erupted 8 times since 1663, and 4 times in about the last 100 years. The last eruption was in 2000. The next is predicted to be around the year 2020.

When Usuzan erupts, it has a particular pattern. First comes about 32 hours or longer of frequent earthquakes, followed by ground deformation, and then the eruption itself. This means evacuation is usually able to be carried out before the eruption begins, and so people living in the town don't seem to mind.

The other pattern shown by Usuzan is that the location of the eruption changes each time, and that eruptions from the summit itself are quite rare. In 1943, a farmer at the foot of the mountain noticed a bump forming in his field. Within 2 years, a 400m high mountain had formed, now known as Showa Shinzan.

As this occurred during the war, the government were keen to keep the new mountain a secret, since they believed it could be taken as an unlucky wartime omen, and so proper scientific measurements couldn't be kept. The local postmaster, Masao Mimatsu, bought the volcano. He kept records of its growth using methods he devised himself, and which are now considered to be standard practise.


Showa Shinzan


Another shot of Showa Shinzan, with a statue of postmaster Masao Mimatsu at the bottom


View down on Showa Shinzan from the top of Usuzan


Masao Mimatsu's diagram of the growth of the mountain

Usuzan erupted again in 1978-79, this time from the summit. A large crater was formed, and volcanic mudflows (lahars) caused extensive damage to the town below. A huge ash column formed and pyroclasts and volcanic bombs rained down below.


The crater at the peak of Usuzan, formed by the '78-79 eruption


Lava dome at the peak


View across Lake Toya from the top of Usuzan, showing the shape of the caldera lake

In 2000, Usuzan erupted again. This time it erupted from the western flank, creating new craters deforming the land as it had in previous eruptions. Mudflows once again did massive damage, volcanic bombs rained down on the tow, and ground deformation left roads unusable.


Truck damaged by ashfall and volcanic bombs from the 2000 eruption

Much of the damage caused by this eruption has been preserved along a few walkable 'promenades' in the area, which are surely unlike anything else you'll find elsewhere.

The Nishiyamagawa promenade shows the damage caused by mudflows.


I think this may have been an onsen building, but I'm not sure


Apartment building - mudflows entered as far as the second floor


This bridge was washed downstream by the lahar


Overview of the whole area

The Nishiyama Crater promenade takes you around the actual site of the 2000 eruption. The eruption occured right next to a major local road, which was thankfully not in use since the evacuation had been completed on time.


The old road leading towards where the new crater formed (steam column is coming from the crater)


Apparently the road was uplifted a total of 50m by the ground deformation


Proof that I was there, in the pouring rain. I had to walk 4km total there and back, plus 3km total along the boardwalk, so I was pretty wet.


Crater formed by the 2000 eruption


More of the still-steaming crater area


Building destroyed by ground deformation and volcanic bombs


...and more...


...and more...


This is what a volcanic bomb does to the roof of a bus


Elementary school near the eruption site


Volcanic bomb still stuck in the wall of the school

Unzen, Sakurajima and Aso were all spectacular in their own ways, but I think this area is surely the most impressive I've visited in Japan or elsewhere (arguably even above Yellowstone, in this regard).

As well as the volcano(es), which I knew were here, if not how impressive they were, this little town had a couple of other suprises up its sleeve.

Firstly, it turns out that the 2008 G8 Summit is being held here. It's interesting to see what a sudden influx of government money does to a small town, with solar panels and wind turbines everywhere to try to impress the visitors, and what appeared to be a brand new building for the summit itself. That said though, the place still had its small-town charm, which made a really nice change from cities like Tokyo, Sapporo and even Asahikawa.


Countdown clock to the 2008 Toyako G8 Summit

The second suprise was one you only see for 15 minutes. Every night, between about March and October, a huge boat goes out onto the lake and launches a full fireworks display over the water. I have no idea why (it's not just a G8 thing) but it's certainly spectacular, and I caught it both nights I stayed there.


Fireworks over Lake Toya


More fireworks, obviously

And so there you have it - Lake Toya. Certainly one of the most suprisingly places I've been in Japan, and probably one of my favourites, too.

As I type this I'm in Hakodate, about the most southern city in Hokkaido, ready to catch a train further south back to Honshu tomorrow. I'll probably stay in Sendai a night or two, and see where I go from there, with an overall aim of heading back down to the Kansai area (Osaka, Kyoto, Kobe) within a week or so.

Anyway, until next time,
James