List of rivers that have reversed direction
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A number of rivers are known to have reversed the direction of their flow, either permanently or temporarily, in response to geological activity, weather events, climate change, or direct human intervention.
Permanent reversals[]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/5/52/Chicago-Sanitary-and-Ship-Canal.jpg/280px-Chicago-Sanitary-and-Ship-Canal.jpg)
Construction of the Chicago Sanitary and Ship Canal
River | Original outlet | Current outlet | Continent | Date of reversal | Cause of reversal | References |
---|---|---|---|---|---|---|
Amazon River | Pacific Ocean | Atlantic Ocean | South America | Cretaceous period | Formation of Andes Mountains | [1] |
Chicago River | Lake Michigan | Mississippi River | North America | 1900 | Construction of Chicago Sanitary and Ship Canal | [1] |
Temporary reversals[]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/8/8c/ReversingFalls_inbound.jpg/280px-ReversingFalls_inbound.jpg)
Intermittent reversals[]
Hurricane storm surges often cause temporary reversals of coastal rivers.[1]
River | Outlet | Continent | Date of reversal | Cause of reversal | References |
---|---|---|---|---|---|
Chicago River[a] | Mississippi River | North America | 2017 and others[b] | Storm surge | [2] |
Mississippi River | Gulf of Mexico | North America | 1812 | Tectonic uplift caused by New Madrid earthquakes | [3] |
2005 | Storm surge from Hurricane Katrina | [1] | |||
2012 | Storm surge from Hurricane Isaac | [1][4] | |||
2021 | Storm surge from Hurricane Ida | [5] |
Regular reversals[]
All tidal sections of rivers reverse their flow with the tide about twice a day, by definition. The Hudson and the Saint John River are just examples.[6]
River | Outlet | Continent | Frequency of reversal | Cause of reversal | References |
---|---|---|---|---|---|
Hudson River | Upper New York Bay | North America | semidiurnal | Tide in Upper New York Bay | [6] |
Petexbatún River | Pasión River | Central America | annual | Winter rain flooding of the Pasión River | [7] |
Qiantang River | Hangzhou Bay | Asia | annually around August 15th | Tidal bore in Hangzhou Bay | [8] |
Saint John River (Reversing Falls) | Bay of Fundy | North America | semidiurnal | Tide in the Bay of Fundy | [9] |
Tonlé Sap River | Mekong River | Asia | annual | Monsoon flooding of the Mekong River | [10] |
See also[]
- Stream capture, in which a stream or river is diverted from its own bed, and flows instead down a neighboring channel
References[]
- ^ a b c d e Borneman, Elizabeth (November 24, 2014). "Rivers that Flow Backwards". Geo Lounge. Retrieved 18 March 2019.
- ^ a b "How Climate Change Is Making This River Run Backwards". EcoWatch. Natural Resources Defense Council. June 4, 2017. Retrieved 19 March 2019.
- ^ Soniak, Matt (January 25, 2013). "Has a U.S. River Run Backwards Before?". Mental Floss. Retrieved 18 March 2019.
- ^ "Mississippi River Flows Backwards Due to Isaac". USGS Newsroom. United States Geological Survey. August 29, 2012. Retrieved 19 March 2019.
- ^ "Hurricane Ida Is So Strong It Reversed the Mississippi's Current". interestingengineering.com. 2021-08-30. Retrieved 2021-08-30.
- ^ a b "The Hudson Estuary: A River That Flows Two Ways". New York State Department of Environmental Conservation. Retrieved 19 March 2019.
- ^ The Petexbatún eco-system (in Spanish) Retrieved 30 January 2021.
- ^ The Bore Tides of the Qiantang River Retrieved 30 January 2021.
- ^ "Reversing Falls". New-Brunswick.net. Retrieved 18 March 2019.
- ^ Jennings, Ken (February 2, 2015). "Why the Tonle Sap River Is Unlike Any Other River in the World". Condé Nast Traveler. Retrieved 18 March 2019.
Categories:
- Lists of rivers
- Hydrology
- Fluvial geomorphology