Nullah
Encyclopedia
A Nullah or Nulla is an arm of the sea
, stream
, or watercourse
, a steep narrow valley
. Like the wadi
of the Arabs, the nullah is characteristic of mountainous or hilly country where there is little rainfall. In the drier parts of India
, and in many parts of Australia
there are small steep-sided valleys penetrating the hills, clothed with rough brushwood or small trees growing in the stony soil. During occasional heavy rains torrents rush down the nullahs and quickly disappear. There is little local action upon the sides, while the bed is lowered, and consequently these valleys are narrow and steep.
In Hong Kong
, a nullah is typically a concrete lined channel designed to allow rapid run off of storm water from high ground, to prevent flooding of urbanised coastal areas.
Arm of the sea
An arm of the sea may refer to a sea loch or:*Arms of the Sea, a 2006 album by Celtic musician Heather Alexander*Nullah, in Hindi*Gulf of Lune, a fictitious sea arm in J.R.R. Tolkien's Middle-earth fantasy universe...
, stream
Stream
A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...
, or watercourse
Watercourse
A watercourse is any flowing body of water. These include rivers, streams, anabranches, and so forth.-See also:* physical geography* Environmental flow* Waterway* Hydrology* Wadi-External links:...
, a steep narrow valley
Valley
In geology, a valley or dale is a depression with predominant extent in one direction. A very deep river valley may be called a canyon or gorge.The terms U-shaped and V-shaped are descriptive terms of geography to characterize the form of valleys...
. Like the wadi
Wadi
Wadi is the Arabic term traditionally referring to a valley. In some cases, it may refer to a dry riverbed that contains water only during times of heavy rain or simply an intermittent stream.-Variant names:...
of the Arabs, the nullah is characteristic of mountainous or hilly country where there is little rainfall. In the drier parts of India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
, and in many parts of Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
there are small steep-sided valleys penetrating the hills, clothed with rough brushwood or small trees growing in the stony soil. During occasional heavy rains torrents rush down the nullahs and quickly disappear. There is little local action upon the sides, while the bed is lowered, and consequently these valleys are narrow and steep.
In Hong Kong
Hong Kong
Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...
, a nullah is typically a concrete lined channel designed to allow rapid run off of storm water from high ground, to prevent flooding of urbanised coastal areas.