The Tale of Hebgen Lake

backroadblues:

Friday, August 2, 2013 – Hebgen Lake, Quake Lake and Whitefish, MT It was a warm summer day at Yellowstone Park. The couple had been camping at several different spots. They had visited the park the day before and they were witness to several odd events. Geysers that hadn’t erupted in years were suddenly erupting with unexpected regularity. Other geysers that typically would erupt for a minute or two were erupting on this day for up to 2 hours. Also, several of the thermal pools that ordinarily shimmered like jewels with clear transparent water of varying hues of blues, greens, reds and oranges on this particular day they had become roiling muddy messes. It was as if the earth itself was ill at ease, as if it was belching its unhappiness with something unknown.That evening, the couple decided to head down to set up camp at Hegben lake out on route 287. There was a dam that was built in 1919 along the Madison River to help widen and deepen the lake and also to better control the flow of the river in times of heavy rains or high snow melt. Beyond the dam, the Madison River flowed gently and calmly toward the town of Ennis. Most people camping along the river would opt to camp on the south side downstream from the dam and just below Sheep Mountain. These campsites would give the eager fishermen quick and easy access to the river in the early morning. On this night the couple opted to stay at a cabin on the north side of the river. They had selected a spot on higher ground so that they could have a nice view of Lake Hegben and of the river down below.The couple thought it felt a bit warmer than usual for this time of the year. Yes, it was summer, but at this altitude the temperature would usually drop dramatically as the sun went down – but not tonight. Here it was coming up on 11:30 PM and the couple could still see the outline of the lake and the river in the near full moon. By this time of the evening, the multitude of birds that make their home along the river would normally be comfortably nesting in the trees. But on this night the birds were anything but comfortable. They seemed to be flying in large flocks from one tree to another seemingly unsure of where they needed to be. Also, the horses in the nearby stables were equally uneasy. They were banging against the metal pipes of the coral and throwing up a lot of dust in the air. It made the couple nervous that perhaps a bear may be on the prowl nearby. Lastly, in the far off distance they could hear the howls of wolves. They first assumed that this was normal due to the near full moon on this warm cloudless night. But the howls were different; they were not the typical plaintiff wails that the couple had heard before. There seemed to be an unknown tension in the howls that permeated the air.At 11:36PM, the events that would change the landscape forever began. It started with a very large bump in the night. The kind you might feel if you had stumbled out of bed in the dark of night and accidently run into a nightstand. It was hard and solid and it was felt by both of the campers. At 11:37 the sound of rumbling began to grow from deep inside of the earth. It soon sounded as if a thousand locomotives were rumbling straight toward the campers. Then the earth began to heave violently; first side-to-side and then violently up and down. The tremors were so large it tossed the campers completely from their beds as if they were rag dolls. Everything in the cabin was being thrown all about. Window were crashing and imploding in to the cabin. All the couple could do was hold on to one another and huddle as best they could under and amid the beds and furniture that by now had been strewn haphazardly about the cabin. The shaking lasted for what seemed like an eternity, when in fact it lasted about 40 seconds – less than a minute. As the tremors began to abate, the couple could now hear another huge roar, but this one was different than the first. The first seemed to be coming up from the bowels of the earth and this rumbling seemed to be much closer. The couple stumbled out of what was left of their cabin, just in time to look up and see that a large part of Sheep Mountain was racing down toward the river. The falling boulders and earth were snapping over 100 year old trees as if they were toothpicks. The scale of the avalanche was larger than anything anyone had ever seen before. The mountainside continued to rain down on the river. Suddenly, the couple looked at one another with horror as they realized that the spot where the campers were staying was now buried under tons of rock and debris. The slide was so great that the debris had now formed a huge earthen dam stopping the river in its tracks. The river by now was not the gentle and peaceful flow they were accustomed to seeing it was now a raging torrent. The couple ran further up the hill to look at Hebgen Lake and the dam that was built in 1919. Did it survive the earthquake, they wondered. As they crested the ridge the lake was now fully in sight and they could not believe what they saw. The Lake was now awash in huge waves towering 20 to 50 feet high and those waves were crashing over the entire length of the dam. The dam appeared to be in tact, but the water was rushing over the dam with such force, it was as if the dam was 10 feet lower than it had been before the earthquake struck. It was clear now that the force of the earthquake that was sufficient to bring down half of a mountain taking 28 people to their certain death was also powerful enough to “tilt” Hebgen Lake. It was now clear that the huge waves were caused by the tremendous shift in the lake. The eastern part of the lake was now much higher, by as much as 7 feet in parts, and the western part of the lake that included the dam was now lower by several feet. The fact that the dam had withstood the violence of the evening at all was indeed a miracle. The question was, would it survive the torrent of water from Lake Hebgen that was rushing over the dam.By morning, the torrent of water raging over the dam at Lake Hebgen had slowed and another huge lake had now been formed beyond the dam. This new lake was a result of the new natural dam created by the massive avalanche. This new lake would be as deep as 190 feet in parts and the unending flow of the river caused the water to continue to rise up the face of this natural dam and it soon crested the dam. Far away in the town of Ennis, the townspeople although shaken by the powerful earthquake were quickly gathering their belongings and heading to higher ground. The fear was that if either the dam at Lake Hebgen or the natural dam were to give way, the ensuing release of water would crush the small town, washing it completely off the map.There were countless miracles that night. Both dams held up and although the damage from the 7.5 Richter Scale earthquake was extensive, the only loss of life were the campers who had the bad luck to camp below Sheep Mountain on that fateful night. Damage to roads and buildings were extensive. These things could be rebuilt over time. Many features in Yellowstone were altered, but Mother Nature takes these things in stride. This fictionalized account is how I imagine events may have unfolded on that fateful night of August 17, 1959. What is true is that it was a warm August night, the sky was clear and it was the eve of a full moon. A 7.5 scale quake did occur.. Hebgen Lake was tilted on end and Sheep Mountain did come tumbling down. A new lake, which still stands was created and is now named Quake Lake. When the mountain came crashing down, 28 people did lose there lives. In the aftermath of the quake one of the largest Army Corps on Engineer projects was undertaken; first to repair the extensive damage to the 1919 dam; then to move and restructure the natural dam that was created so that it would withstand erosion. What is also true is that what we now call Quake Lake did not exist before the evening of August 17, 1959. That lake is now 6 miles in length and it is over 190 feet deep in parts. The remnants of tall pine trees can still be seen poking up out of Quake Lake. Photo 1&2 – a view if Hebgen lake on Rte 287 heading west Photo 3 – a view of Sheep Mountain, or what is left of it Photo 4 – a view of Quake Lake – you can see the trees from the forest that the lake covered in 1959 Photo 5 – down stream from Quake Lake the Madison River flows like nothing ever happened.