A backwater is a part of a river in which there is little or no current. It refers either to a branch of a main river which lies alongside it and then rejoins it or to a body of water in a main river which is backed up by an obstruction such as the tide or a dam.
If a river has developed one or more alternative courses in its evolution, then one channel is usually designated the main course and secondary channels may be termed backwaters. The main river course will usually have the fastest stream and will likely be the main navigation route, whereas backwaters may be more shallow and flow more slowly if at all. This results in a more diverse environment that is of scientific interest and worthy of preservation. Backwaters also provide opportunities for leisure activities such as canoeing and fishing.
In this sense, the term is extended to apply to physical and social areas that have been by-passed. It may apply to places that have been neglected in economic development or in the expression a "cultural backwater".
Water backed up by an obstruction
When a section of a river is near the coast or another feature that sets its base level, then the section which is influenced by the conditions at its mouth is termed a backwater. If a river flows into a lake or sea, this is the region in which the slope of the river decreases because the lower water flux permitted at the mouth causes the water to back up. Where the river outlet is strongly affected by tides, this cyclic change in base level changes the portion of the river that is a backwater. As a result fresh and salt water may become mixed to form an estuarine environment.
- Merriam Webster Dictionary
- Wargrave Local History Society Latest News - November 2003 Hennerton and the Backwater
- E. HOHAUSOVÁ, P. JURAJDA Restoration of a river backwater and its influence on fish assemblage Czech J. Anim. Sci., 50, 2005 (10): 473–482
- John C. Marlin BACKWATER RESTORATION OPPORTUNITIES: ILLINOIS RIVER Waste Management and Research Center, Illinois Department of Natural Resources One
- Vistt Thames Free Family Fun
- Suggested paddles Cliveden Reach on the Thames
- The Cambridge Economic History of Modern Britain
- Australian Broadcasting Corporation - Australia's century of federation A Cultural Backwater Date of Broadcast: Monday, 25 June 2001
- Southard, John B. (2006). "Chapter 5: Open-Channel Flow". An Introduction to Fluid Motions, Sediment Transport, and Current-generated Sedimentary Structures. MIT OpenCourseWare. Retrieved 16 March 2010.