Triple watershed

A triple divide or triple watershed is a point on the Earth's surface where three drainage basins meet. If two river basins come together at a drainage divide, the meeting of three basins always occurs at the meeting of two drainage divides. Some triple divides are prominent mountain peaks, but often they are minor side peaks, or even simple slope changes on a ridge which are otherwise unremarkable.

Topographic triple divides do not necessarily respect the underground path of water. Thus, depending on the infiltration and the different geological layers, the hydrologic triple divide is often offset from the topographic triple divide.

The term hydrological apex refers to a triple divide considered the dominant one of a whole continent, because its waters flow into three different oceans. Triple Divide Peak in Montana is considered the triple divide "hydrological apex" of North America, though Snow Dome on the Alberta-British Columbia border also has a claim depending on how the Arctic and Atlantic oceans are defined. North America is the only continent, excluding the Antarctica ice fields, that has a triple point dividing basins draining into three different oceans.

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