Tidal race

Tidal race or tidal rapid is a natural occurrence whereby a fast-moving tide passes through a constriction, resulting in the formation of waves, eddies and hazardous currents. The constriction can be a passage where the sides narrow, for example the Gulf of Corryvreckan and the Saltstraumen maelstrom, or an underwater obstruction (a reef or rising seabed), such as is found at the Portland Race in the United Kingdom.

In extreme cases, such as Skookumchuck Narrows in British Columbia, through which tides can travel at more than 17 knots, very large whirlpools develop, which can be extremely hazardous to navigation.

Notable tidal races

Cape Reinga in New Zealand
Skookumchuck Narrows in British Columbia, Canada
The Bitches in Wales, United Kingdom^[1]^[2]^[3]^[4]^[5]
Falls of Lora in Scotland, United Kingdom
Portland Bill on the Isle of Portland, United Kingdom
The Alderney Race (12 knots+) between Alderney and La Hague, Normandy, France
The Raz de Sein in western Brittany, France
The Fromveur Passage in western Brittany, France
Horizontal Falls in Western Australia, Australia
Naruto Strait between Shikoku and Awaji Islands, Japan
Reversing Falls in Saint John, New Brunswick, Canada

Sources

^ "Nature"
^ The-Bitches.co.uk
^ UK Riversguidebook
^ CanoeWales Archived 2014-09-11 at the Wayback Machine
^ "Bitches and Tides"

[1] "Nature"

[2] The-Bitches.co.uk

[3] UK Riversguidebook

[4] CanoeWales Archived 2014-09-11 at the Wayback Machine

[5] "Bitches and Tides"

[1]

[2]

[3]

[4]

[5]

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Notable tidal races

See also

Sources