List of rivers that have reversed direction

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, tides, or direct human intervention.

Permanent reversals Natural 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 Wisconsin River Great Lakes Basin Mississippi River North America Pleistocene Epoch Pre-Illinoian glaciers

Artificial River Original outlet Current outlet Continent Date of reversal Cause of reversal References Chicago River Lake Michigan Mississippi River North America 1900 Construction of Chicago Sanitary and Ship Canal

Temporary reversals Daily All tidal sections of rivers reverse their flow with the tide about twice a day (or semidiurnally), by definition. The following are notable examples.

River Outlet Continent References Hudson River Upper New York Bay North America Saint John River (Reversing Falls) Bay of Fundy North America Salmon River Bay of Fundy North America Channel of Vivari Straits of Corfu Europe Butrint National Park - Combining Natural Park with Cultural Heritage Retrieved 8 May 2024.

Annual River Outlet Continent Cause of reversal References Krupa River Neretva River Europe High water levels of the Neretva River Krupa River Retrieved 30 August 2022. Petexbatún River Pasión River Central America Winter rain flooding of the Pasión River The Petexbatún eco-system (in Spanish) Retrieved 30 January 2021. Qiantang River Hangzhou Bay Asia Tidal bore in Hangzhou Bay The Bore Tides of the Qiantang River Retrieved 30 January 2021. Tonlé Sap River Mekong River Asia Monsoon flooding of the Mekong River

Intermittent Hurricane storm surges often cause temporary reversals of coastal rivers.

River Outlet Continent Date of reversal Cause of reversal References Chicago River Mississippi River North America 2017 and others Storm surge Mississippi River Gulf of Mexico North America 1812 Tectonic uplift caused by New Madrid earthquakes 2005 Storm surge from Hurricane Katrina 2012 Storm surge from Hurricane Isaac 2021Storm surge from Hurricane Ida

See also Stream capture, in which a stream or river is diverted from its own bed, and flows instead down a neighboring channel

References