Ragundasjön

Döda fallet (The dead fall) is a former whitewater rapid in of the river Indalsälven in Ragunda Municipality in the eastern part of the province of Jämtland in Sweden. Glacial debris had blocked the course of the Indalsälven at Döda fallet for thousands of years, creating a reservoir of glacial meltwater 25 km (16 mi) in length known as Lake Ragundasjön. The river water flowed over this dam of debris in a high waterfall known as Gedungsen or Storforsen (The great whitewater rapid). It was one of the most impressive waterfalls in Sweden with a total fall height of about 35 meters (115 feet) and a large water discharge.

The lake and falls were destroyed in 1796 after a flood rerouted the river through a small canal constructed to bypass the falls, emptying the entire lake within hours.

The Indalsälven flows through a valley between mountains in Jämtland province of Sweden. In one place its course before the Ice Age went south of a high rock spur with a round mountain in its end sticking out of the valley's north side. In the Ice Age its course past that spur was filled with glacial and periglacial deposit, and after the ice retreated the river flowed further north, over the neck of the spur, causing Storforsen.

In the late 18th century, logging emerged as a major industry in the heavily forested region of Jämtland. The rivers were used as fast and relatively easy transportation of the timber to the coastal sawmills. The whitewater rapid Storforsen however was a major obstacle as it damaged or destroyed much of the timber, forcing use of land transportation (portaging) past the waterfall. Another issue was that salmon could not swim upstream through Storforsen, and this made the fishing downstream good, but poor upstream.

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