portage

Nie jestem jednak pewien.

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Note added at 55 mins (2017-09-01 16:05:22 GMT)
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https://en.wikipedia.org/wiki/Portage
https://en.oxforddictionaries.com/definition/portage
http://www.thefreedictionary.com/portage

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Note added at 1 hr (2017-09-01 16:15:53 GMT)
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Portage—an overland route of travel between navigable bodies of water.
An overland passage connecting two bodies of water.
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“Portage" means an overland route for manually carrying boats and supplies around dams.
https://docs.legis.wisconsin.gov/code/admin_code/nr/300/330

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Note added at 1 hr (2017-09-01 16:20:46 GMT)
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The world-famous Soo Locks form a passage for deep-draft ships around the rapids in the St. Marys River. Before white men came to the area, the Ojibway Indians who lived nearby portaged their canoes around the "Bawating" (rapids) to reach Lake Superior from the St. Marys River.
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In 1797, the Northwest Fur Company constructed a navigation lock 38 feet long on the Canadian side of the river for small boats. This lock remained in use until destroyed in the War of 1812. Freight and boats were again portaged around the rapids.
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While there is some debate on the exact meaning of "Sault," scholars of early French note that the word translates into jump, referring to the place where one needs to "jump", or put into the St. Mary’s River. This translation relates to the treacherous rapids and cascades that fall over 20 feet from the level of Lake Superior to the level of the lower lakes. Hundreds of years ago, this prohibited boat traffic and necessitated an overland portage from one lake to the other. This is how Portage Avenue, the main street running along the river, got its name.
https://www.saultcity.com/historic-homes