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head of navigation

n. (context nautical English) The farthest point above the mouth of a river that can be navigated by ships. This term can be somewhat subjective on many streams, as this point may vary greatly with the size of the ship being contemplated for navigation. On others it is quite objective, being caused by a waterfall, dam or lock.

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Head of navigation

Head of navigation is the farthest point above the mouth of a river that can be navigated by ships. Determining the head of navigation can be subjective on many streams, as this point may vary greatly with the size of the ship being contemplated for navigation and the seasonal water level. On others, it is quite objective, being caused by a waterfall or a dam without navigation locks.

Usage examples of "head of navigation".

Where a waterfall marked the head of navigation on that great river known variously as the Zeus, Mississippi and Longflood, a basically agricultural people who had not developed air transport as far as in Eutopia were sure to build a city.

It will doubtless take us half of the remaining time just to walk to the head of navigation on the river.

It was head of navigation on the Colorado, and last I'd seen there were only three or four buildings there, and about that many folks.