Idaho is a relatively seismic state, but in terms of weather is blessedly mild with regards to devastating acts of nature. While natural, large-scale events impact the state every year, only a few events across the country receive formal Federal Major Disaster Declarations from the President, a program which was created in the 1950s. At the time of writing and since the program began, 23 major disasters have been declared in Idaho, along with two federal emergency and 10 fire management assistance declarations.
Idaho is a wonderful place to live; however, the same natural and geologic forces that make it so beautiful can often result in natural disasters of epic proportions. These five events, while they may or may not have been registered as Federal disasters, were devastating enough to Idaho's population, landscape, and industry that they make notable historical moments. These five natural disasters in Idaho also mark incredible moments of our state coming together to help those in affected communities recover and promote healing across the Gem State.
1. Borah Quake, 1983
It was one of the most powerful temblors to strike North America in the 20th century at 7.3 on the Richter scale... but did you know Idaho is at risk for more natural disasters just like it? The Borah Quake struck the middle of Idaho's wilderness, rattling Challis and the Lost River Valley. Two were killed, with total damages exceeding $2.5 Million - not including the irreplaceable and inexplicable disappearance of natural spring water which was used to maintain local livestock.
The quake made global headlines not only for its magnitude, but because its faulting was up and down, whereas most other earthquake zones shift side to side. Most notably, this horrific natural disaster caused Mount Borah - already Idaho's tallest peak - to grow by around six inches, while also dropping the entire valley anywhere from five to nine feet. Also created? One giant rift and a number of sinkholes, some over 10 feet across, pocking the valley floor. These holes were caused by soil "liquefaction" - the violent shaking of loose earth until it compacts into a quicksand-like material. The 21-mile long scarp that was created by the Borah Quake is raised at points by as much as 14 feet and is still visible today. You cross the scarp on the west side of the mountain en route to the Borah trailhead.
But be warned: Idaho has two other "natural wonders" in its landscape that are a part two
waiting to happen.
2. The Plague, 1985
In a plague of biblical proportions, and with infestations so bad in parts of the state that the ground was literally crawling, historical reports document an incredible natural disaster never before seen in Idaho: the Grasshopper Epidemic of 1985. This unrivaled natural disaster caused severe crop damage to more than 6 million acres in the state. The insects would enter the edge of a field and munch their way through from start to finish, leaving no stalk untouched.
The grasshopper swarms occurred throughout the Northwest, but the U.S. Department of Agriculture specifically declared four counties in Idaho to be disaster areas - total damages exceeded $11 Million in the first year alone. The disaster was compounded by the state's drought conditions and simultaneous hatching of Mormon crickets. Fortunately, heavy aerial pesticide attacks and a lucky break of cooler-than-normal weather in 1987 finally enabled farmers across the state to get an edge against the crop-devouring adversaries. Not-so-fun Fact: 17 grasshoppers per square yard can devour one ton of alfalfa per day.
3. The Big Burn, 1910
Idaho was home to the largest forest fire in US history in 1910, which burned through Northern Idaho on August 20 and 21. A dry summer, sudden lighting, and intense wind combined to create the incalculable inferno. Over three million acres of virgin timberland were destroyed across three states by the blaze, which also took 87 lives. Idaho is no stranger to devastating wildfires, but the Big Burn was a disaster of different proportions. Horrifyingly, most of the damage was due to hurricane-force winds that turned the immense wildfire into a venerable blowtorch, with flames that could be seen shooting straight into the air.
Red balls of fire rolled up mountainsides; crown fires, some up to 10 miles wide, streaked through treetops while the central blaze consumed everything in its path at an incredible 70 miles per hour. The sky was pitch black with ash that mid-afternoon, save for the blinding red glow of the blaze. Since the area had received only an inch or so of rain that season - a mere fraction of the normal rainfall - the crisp, withered trees made perfect tinder. Meanwhile, thousands of other fires burned nearby and were all left to die out of their own accord as all resources were allocated towards combating the behemoth flames.
With U.S. military assistance, the flames seemed to be contained. Then, on Aug. 20, the red-hot forest exploded into "The Big Blowup." A cold front moved in and fed the flames with new oxygen, combining multiple smaller fires into one incinerating vortex. The fire was only placated by the arrival of rain, and ultimately, was the first test of the newly established U.S. Forest Service (1905).
You can learn more about the Big Burn of 1910 by paying a visit to the town of Wallace in Northern Idaho, where you can see some of the remnants firsthand.
4. Salmon Flood, 1984
Where the Salmon and Lemhi rivers meet, unusually cold temperatures in 1984 caused two ice jams to form along the river. Ice jams are caused when a buildup of ice blocks the river’s flow, causing the water upstream to slow down and rise higher. If the jam suddenly breaks apart, rapidly releasing upstream water and causing large-scale flash flood conditions. That chilly winter, freezing temperatures allowed the formation of "frazil ice," a slushy ice that forms in turbulent open waters, which then began sticking together in two separate instances only a week apart in December. They reached 22 and 30 miles long, respectively. Frigid waters flooded the small town of Salmon, Idaho causing mass evacuations and rescues, with relief and cleanup efforts hindered by emergency funds depleted by the Borah Quake the year before.
No lives were lost in this natural disaster, but the damage was severe. When the floodwaters receded, residents found nearly three feet of ice inside their homes and five feet of ice outside. The subzero temperatures had literally left the town encased in ice. Ultimately, a Presidential disaster declaration was made.
5. Mount St. Helens, 1980
In 1980, Idaho was plunged into darkness when Washington's landmark volcano collapsed and erupted in a lateral explosion of magma and ash. The state was coated in around two inches of volcanic ash, which is composed of tiny shards of pointed glass and rock that form a concrete-like material when wet and can significantly damage a person’s lungs. Washington was immediately declared a natural disaster area, and Idaho was declared one the following day.
While the eruption and subsequent ash didn’t cause severe injury or loss of life in Idaho directly, it was a disaster of its own accord projected to have cost tens of millions of dollars in loss of business, clean-up, and vehicle damage. Thousands of residents also suffered lung damage from inhaling the dangerous substance.
Wow. Idaho is incredibly fortunate to have not only recovered from these devastating events but to have quite literally "grown" from them. Our state's sense of community is unrivaled, and had Idahoans not banded together in these times of need, the damage could have been much worse.
Were you or a family member in Idaho or nearby when any of these natural disasters occurred? Feel free to share your stories and pay tribute to the countless organizations and individuals who played roles in the aftermath.
Man-made disasters can wreak havoc on an entirely different scale. The collapse of the Teton Dam in 1976 is one such disaster that, while it wasn't caused by Mother Nature, was just as devastating as those listed above.
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