Backwater (river)

Source: Wikipedia, the free encyclopedia.

A backwater is a part of a river in which there is little or no current. It can refer 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, backed up by the sea tide or by an obstruction such as a dam.[1] Manmade restrictions to natural stream flow or temporary natural obstructions such as ice jams, vegetation blockage, or flooding of a lower stream can create backwater.[2]

Alternative channel

A Kerala houseboat in Kumarakom, India

If a river has developed one or more alternative courses in its evolution, one channel is usually designated the main course, and secondary channels may be termed backwaters.[3] The main river course will usually have the fastest stream and will likely be the main navigation route; backwaters may be shallower and flow more slowly, if at all. Some backwaters are rich in mangrove forest.[4] This results in a more diverse environment of scientific interest and worthy of preservation.[5][6] Backwaters also provide opportunities for leisure activities such as canoeing and fishing.[7][8]

The term has been applied as a metaphor to physical and social areas that have been bypassed. It may apply to places that have been neglected in economic development,[9] or in the expression a "cultural backwater".[10]

Water backed up by an obstruction

Kumarakom lake in Kerala backwaters

When a section of a river is near the coast or another feature that sets its

tides, the 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.[11]

See also

References

  1. ^ Merriam Webster Dictionary
  2. ^ Langbein, W. B.; Iseri, Kathleen T. (1960). "General Introduction and Hydrologic Definitions, Manual of Hydrology: Part 1. General Surface-Water Techniques" (PDF). pubs.usgs.gov. Geological Survey Water Supply Paper 1542-F. U.S. Geological Survey. Retrieved February 10, 2019.
  3. ^ Wargrave Local History Society Latest News - November 2003 Hennerton and the Backwater Archived 2011-07-24 at the Wayback Machine
  4. ^ "Chettuva in Thrissur: Flaunting Kerala's biggest mangrove forest". OnManorama. Retrieved 2018-08-28.
  5. ^ "E. HOHAUSOVÁ, P. JURAJDA Restoration of a river backwater and its influence on fish assemblage Czech J. Anim. Sci., 50, 2005 (10): 473–482" (PDF). Archived from the original (PDF) on 2017-07-05. Retrieved 2010-07-29.
  6. ^ "John C. Marlin BACKWATER RESTORATION OPPORTUNITIES: ILLINOIS RIVER Waste Management and Research Center, Illinois Department of Natural Resources One" (PDF). Archived from the original (PDF) on 2016-03-03. Retrieved 2010-07-29.
  7. ^ "Vistt Thames Free Family Fun". Archived from the original on 2012-01-25. Retrieved 2010-07-29.
  8. ^ "Suggested paddles Cliveden Reach on the Thames". Archived from the original on 2010-07-23. Retrieved 2010-07-29.
  9. ^ The Cambridge Economic History of Modern Britain
  10. ISSN 0099-9660
    . Retrieved 2018-10-07.
  11. ^ Southard, John B. (2006). "Chapter 5: Open-Channel Flow" (PDF). An Introduction to Fluid Motions, Sediment Transport, and Current-generated Sedimentary Structures. MIT OpenCourseWare. Retrieved 16 March 2010.