In 1976, America was celebrating it's 200 year birthday and Colorado its 100th. No one expected a flood to temper Colorado's celebration, though.

The Big Thompson River is 78 miles long and is a tributary of the Platte River and flows through Rocky Mountain National Park. Flowing through Thompson Canyon, as it always had, the river was usually quite serene. But on July 31, 1976, something happened to change all of that.

Twelve inches of rain fell in less than four hours, 75% of the annual rainfall for the year for the area. As day turned into night, the river was about to turn deadly.

Around 9 pm, the river, which had held back as long as it could, rushed headlong into Thompson Canyon, producing a 20-foot wall of water that would kill 143 people, five of who were never found. 400 cars, 418 houses and a good portion of Route 34 was wiped out as well.

Flooding returned in 2013 to the area, but not with the devastation the earlier one had. A hydroelectric plant in Loveland as well as well as a reservoir were completely filled with rocks and silt and a good part of the highway was wiped out.

Rebuilding once again, they are hopeful the redesign of several areas will help hold back flood waters, should they rise again. But with flash floods, there is a rule of thumb to follow. It's not if, but when they occur.

It was also recently announced that US 34 would reopen after two years of construction. Let's hope they never go through that again.

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