Wednesday
The road to the visitor centre was cleared and opened to the public on May 10th and we have camped at Toutle ready to visit the mountain. We started as early as possible and drove up the 47 miles to Johnstone Ridge Observatory. We have found out that it was named after one of the scientists who were killed when MSH exploded on May 18th 1980. We arrived at about 10.00 to find that the centre was still closed due to a water pipe breaking (no water - no toilets - no public), but were able to have a good wander round on the many trails. Our visit was made better by a volunteer who gave us a guided tour of the area, showing us many of the features that were changed or added when the eruption took place.
There are two aspects to MSH, one is the sheer size and beauty of the mountain, the other is to see and understand that it is the site of a massive volcanic eruption, the largest in living memory in North America. Johnstone Ridge is on the side of the mountain that was blown away, so you can see all the effects that the eruption had on the area. It is not until one actually experiences the place that one can understand the power and size of the eruption that took place. Although the mountain was still 6 miles away our view point enabled us to see the crater where the volcano had blown away the mountain side, below us we could see the lava plain, ash slurry and bits of mountain that had been rapidly eroded away. The rock ridge we were standing on was curiously bare of ash and we found out that the gas/ash/mountainside had slipped down some 4000 feet from MSH, into the valley area and its momentum had forced it up over the ridge, scrapping the facing side and top bare, before breaking over the ridge into the next valley, or falling back, just like a wave breaking on a seawall. Except the ridge stands 900 feet above the valley below! Awesome really was the word. The ash/debris layer on the valley floor is over 200 feet thick and in places has been washed away into intricate gorges, except the gorges were eroded by the hot slurry within the first few days, not over years as with water. The visibility was excellent and we could even see the steam that is still rising from the magma bulge which is again building inside the crater. Looking around, away from the mountain, one could see tree trunks lying in line with each other, where they that had been felled by the explosion. Except in odd places where they had been protected by the blast by being on the other side of a hill, there they were just dead, but still standing. In the valleys on the way up Sally had spotted tree trunks that had been buried in the ash, but now exposed in the river banks.
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