Earthquake Lake

This trip to Yellowstone has really been diverse for us.  Besides our efforts to see some of the “off-the-beaten-path” stuff and doing new things we had not done before at Yellowstone, we also set out to explore the area outside Yellowstone.  In the north, we did the Beartooth Highway. During our travels these last few weeks, we heard about an area west of Yellowstone that suffered a tremendous earthquake just 60 years ago, and formed Earthquake Lake.  Having moved to the West Yellowstone area we thought it was a great opportunity to explore it.

Earthquake Lake was formed when an earthquake caused the side of a mountain to slide down into the Madison River valley and effectively dam up the Madison River.  It is a fascinating and sad story.  The raw power of nature, the suddenness of tragedy and the resolve to presever.   We stared our journey leaving West Yellowstone on Highway 20 then west on Highway 287. The scenery was a contrast to Yellowstone, populated ranch country and lakeside homes along Hebgen Lake.

There are markers along the route explaining and highlighting the various aspects of the events that happened on Aug. 17, 1959, around midnight, when the quake hit.  The quake was caused when two blocks of the Earth’s crust north of Hebgen Lake dropped over existing faults, setting off an earthquake measuring 7.5 on the Richter scale.  When the fault dropped, it caused the north shore of Hebgen Lake to tilt downward. It sent Seiches, a standing wave,  across the lake flooding lakeside cabins and setting them afloat in the lake.  Many parts of the old Highway 287 were washed away, trapping residents and visitors, sending lakeside cabins into the water and flooding other parts of Highway 287.  The south side of the lake was raised so high that beach front cabins were left dry.  There are stories of people waking up to cabins floating in the lake.

Further along Highway 287 below Hebgen Dam is a campground, Cabin Creek. The night of the quake, this campground was on the faultline.  There was a campsite that straddled the fault.  The scarp the fault created was dramatic.  It split the middle of the campsite leaving the fire ring in place, and the picnic table raised over 20 feet.  This scarp line stretched the length of the fault extending almost 14 miles.  As a testament to the engineers, the dam cracked, but did not fail.

Highway 287 continues along the Madison River and past outfitters and private campgrounds.  The Madison River is long famous for its fly fishing and runs along forming a canyon as it flows west.  We were inspired by its beauty and ruggedness.

Earthquake Lake was formed by the damming up of the Madison River Canyon by a giant landslide, caused by the earthquake.  In less than a month, the lake formed down stream from the dam.  It consumed everything in its path.  The trees, which used to line the river,  are still standing and visible.  Giant tall grey skeletons, the only visible remains of what was once a grand river.  The creation of the lake, and the standing tree trunks have brought new birds, previously never seen in the area, Double Crested Cormorants.

The landslide that dammed up the canyon and formed the lake was over 80 MILLION tons of rock sliding down the mountain creating 100 mph winds.  Nearly half of a 7600 ft mountain broke away and slide down into the river canyon damming up the river.  The slide rocks came down and moved across the valley in just 20 seconds.   There is a memorial and visitors center explaining the events of that night with first-hand accounts from survivors.

Along the river was a National Forest campground, Rock Creek Campground.  This is where the real tragedies occurred.  With the earthquake coming at midnight,  campers were sleeping in their tents.  Some campers were crushed in their tents while the neighboring tent was untouched. The hurricane force winds were so strong it tore off clothing and some people were blown away.  In total, 28 people died in the quake.  26 in the campground.  19 of the bodies were never found.  There is a boulder on the north side of the slide, it came across the valley floating on the top of the slide.  It did not roll or tumble, it just floated like a branch on water.  As a memorial to the people lost in the earthquake, there is a plaque on the bolder with the name of each person that was killed.

Our drive along Highway 287 and visit to Earthquake Lake turned out to be a very moving experience for us.  We had no idea of the massive power of the earthquake, nor of the tragedy that ensued for people who were just out camping for one more vacation before school started.  It was a complete surprise and over in just minutes.  How easily could this have been any one of us who enjoy time in the outdoors?