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Concept
Portage (transport fluvial)
Résumé
Portage or portaging (Canada: pɔːrˈtɑːʒ; ˈpɔːrtɪdʒ) is the practice of carrying water craft or cargo over land, either around an obstacle in a river, or between two bodies of water. A path where items are regularly carried between bodies of water is also called a portage. The term comes from French, where porter means "to carry," as in "portable". In Canada, the term "carrying-place" was sometimes used.
Early French explorers in New France and French Louisiana encountered many rapids and cascades. The Native Americans carried their canoes over land to avoid river obstacles.
Over time, important portages were sometimes provided with canals with locks, and even portage railways. Primitive portaging generally involves carrying the vessel and its contents across the portage in multiple trips. Small canoes can be portaged by carrying them inverted over one's shoulders and the center strut may be designed in the style of a yoke to facilitate this. Historically, voyageurs often employed tump lines on their heads to carry loads on their backs.
Portages can be many kilometers in length, such as the Methye Portage and the Grand Portage (both in North America) often covering hilly or difficult terrain. Some portages involve very little elevation change, such as the very short Mavis Grind in Shetland, which crosses an isthmus.
This section deals mostly with the heavy freight canoes used by the Canadian Voyageurs.
Portage trails usually began as animal tracks and were improved by tramping or blazing. In a few places iron-plated wooden rails were laid to take a handcart. Heavily used routes sometimes evolved into roads when sledges, rollers or oxen were used, as at Methye Portage. Sometimes railways (Champlain and St. Lawrence Railroad) or canals were built.
When going downstream through rapids an experienced voyageur called the guide would inspect the rapids and choose between the heavy work of a portage and the life-threatening risk of running the rapids.
Source officielle
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