Reach (geography)

Source: Wikipedia, the free encyclopedia.

A reach is a segment of a stream, river, or arm of the sea,[citation needed] usually suggesting a straight, level, uninterrupted stretch.[1][2] They are traditionally defined by the capabilities of sailing boats, as a stretch of a watercourse which, because it is straightish, can be sailed in one "reach" (that is, without tacking).

Reaches are often named by those using the river, and a reach may be named for landmarks, natural features, and historical reasons (see, for instance, Gallions' Reach, named after the family that once owned its banks).

A reach may be an expanse, or widening, of a stream or river channel. This commonly occurs after the river or stream is dammed. A reach is similar to an arm, though an arm may bend and thus have multiple reaches. The term "reach" can also refer to a level stretch, as between river rapids or locks in a canal.[citation needed] The word may also be used more generally to refer to any extended portion or stretch of land or water, or even metaphorically.

In fluvial hydrology, a reach is a convenient subdivision of study; it may be any length of river of fairly uniform characteristics, or the length between gauging stations, or simply the length of a watercourse between any two defined points.[3][4] These may be measured in terms of river miles.

As of 2015, the US Board on Geographic Names records 334 place names in the US with the characterization of a named "reach".[5]

Gallery

  • Example: Hanford Reach National Monument, Washington State, US. The last significant free-running (undammed) section of the Columbia River in the US
    Example: Hanford Reach National Monument, Washington State, US. The last significant free-running (undammed) section of the Columbia River in the US
  • A map of the reaches of the River Thames; it can be seen that a reach is a straightish stretch (and can therefore be sailed in one reach, one straight-line path between tacks, unless the wind is too close to head-on to allow the sailing-boat to reach)
    A map of the reaches of the River Thames; it can be seen that a reach is a straightish stretch (and can therefore be sailed in one reach, one straight-line path between tacks, unless the wind is too close to head-on to allow the sailing-boat to reach)
  • Thames barges reaching on the Thames during a race; they are probably on Gravesend Reach
    Thames barges reaching on the Thames during a race; they are probably on Gravesend Reach

See also

References

  1. ^ Macfarlane, Robert, "Landmarks", Hamish Hamilton Press, 2015
  2. ^ Oxford English dictionary, reach, n., third meaning ("part of a river which can be looked upon at once between two bends")
  3. ^ Hydrologic Definitions, Science in Your Watershed, USGS
  4. ^ "Glossary: stream-related terms". Streamnet. 7 December 2014. Archived from the original on 2014-12-07.
  5. ^ USGS Survey GNIS Database