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drainage basin
A parent river the principal channel of a drainage basin; also called a main stem.
The boundary of the drainage basin is called a drainage divide. Sometimes drainage basin is called catchment area referring to an area where water flows into a stream or a number of streams. In North America drainage basin is also called Watershed.
There are lots of possible answers,A drainage basinA watershedA drainage systemDendritic drainage patternTrellis drainage patternParallel drainage patternRectangular drainage patternRadial drainage patternAnnular drainage patternDiscordant drainage patternA spring headTributariesConfluencesA river system
a drainage divide
A canal can be called an artificial waterway.
Because, drainage basins are high elevated
Drainage basins are separated from each other by an area of higher ground called a drainage divide. North America has 5 large Continental Divides that separate the drainage basins of the Pacific, Arctic, and Atlantic Oceans, Hudson Bay, the Great Lakes, and the Gulf of Mexico.
drainage system (guessing)
Drainage basins are separated from each other by an area of higher ground called a divide.
Divides are the boundaries that separate streams in adjacent drainage basin.