flumes

Noun

flume (plural flumes)

1. A ravine or gorge, usually one with water running through.
   • Near the upper end of the portage the river falls 100 feet in as many rods, the water going at lightning speed through a natural flume in the rock. So rapid is the descent that the water in the flume is but 3 feet deep. We named this the "Devil's Slide."1898, Recreation, page 31
2. An open channel or trough used to direct or divert liquids, especially to carry materials (logs, mined material, etc) or people (as a water slide), especially (but not always) one where the walls are raised above the surrounding terrain rather than recessed like a ditch.
   • [...] the flumes are generally not dark rides and they run much faster. Two notable exceptions are the Timber Mountain[…]2001, Dale Samuelson, Wendy Yegoiants, The American Amusement Park, Motorbooks International, →ISBN, page 90

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