freestone
A river or stream fed primarily by rainfall and snowmelt rather than by springs or dam releases. Freestone streams are wilder and more variable than tailwaters — their flows rise and fall with the weather, their temperatures fluctuate with the seasons, and their character changes year to year. The word implies independence from human infrastructure.
Etymology
Originally a masonry term for stone that can be cut freely in any direction. Applied to rivers, it suggests water that runs free — unregulated, undammed, subject only to weather and gravity.
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