Casiquiare canal-Orinoco River hydrographic divide

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Casiquiare canal
Origin	Orinoco River
Mouth	Rio Negro
Basin countries	Venezuela
Length	326 km
Basin area	42,300 km²

The Casiquiare canal-Orinoco River hydrographic divide is a representation of the hydrographic water divide that delineates the separation between the Orinoco Basin from the Amazon Basin. (The Orinoco Basin is west–north–northeast flowing, into the Caribbean; the Amazon Basin is east-flowing into the western Atlantic}. Essentially, a west-flowing, upriver section of Venezuela's Orinoco River has an outflow to the south into the Amazon Basin. This named outflow is the Casiquiare canal, which as it heads downstream, picks up speed and also accumulates water volume. During flood stage, the Casiquiare's main outflow point into the the Rio Negro is supplemented by an overflow that is a second, and more minor entry river bifurcation into the Rio Negro and upstream from its major entry confluence.

The Casiquiare canal connects the upper Orinoco, 9 miles below the mission of Esmeraldas, with the Rio Negro affluent of the Amazon River near the town of San Carlos.

The simplest description-(besides the entire area-floodpain) of the water divide is a "south-bank Orinoco River strip" at the exit point of the Orinoco, also the beginning of the Casiquiare canal. However during the Orinoco's flood stage, that single simply defined beginning of the canal, is turned into a region, and a strip along the southern bank of the Orinoco River.