River source

Starting point of a river

The source or headwater of a river or stream is the geographical point of its beginning, specifically where surface runoff water begins to accumulate into a flowing channel of water. A river or stream into which one or many tributary rivers or streams flow has many headwaters, these being all of the individual headwaters of its tributaries. Each headwater is one of the river or stream's sources, as it is the place where surface runoffs from rainwater, meltwater, or spring water begin accumulating into a more substantial and consistent flow that becomes a first-order tributary of that river or stream.

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