Which one of the following is not a desert river?

Correct — A, Barak. The Barak rises in the Manipur hills, flows west through Assam's Barak valley past Silchar, and crosses into Bangladesh, where it splits into the Surma and the Kushiyara and eventually feeds the Meghna. That is one of the wettest corners of India — the opposite of a desert regime in every respect. The other three are western Indian streams of the arid and semi-arid belt. The Rupen and the Machchhu drain into the Little Rann of Kachchh, and the Banas of north Gujarat ends in the Rann as well, all of them running dry for much of the year and dissipating inland instead of reaching the sea.

• (b)Rupen — A north Gujarat river rising in the Aravalli foothills and losing itself in the Little Rann of Kachchh — an inland-draining stream of the arid belt.
• (c)Banas — The Banas of north Gujarat rises in the Aravallis near Mount Abu and also ends in the Rann. A separate river of the same name in Rajasthan is a Chambal tributary, and either way the name belongs to the dry west.
• (d)Machchhu — A Saurashtra river flowing north past Morbi into the Little Rann. Its dam failure in 1979 is the reason the name is remembered outside Gujarat.

Rivers of the arid west share a set of features that mark them out: they are seasonal or ephemeral, they carry salt, and many of them never reach the sea, ending instead in an inland depression such as the Rann of Kachchh. The Luni is the type example — rising in the Aravallis, turning saline downstream and dissipating in the marshes of the Rann. Rivers of the north-east belong to a completely different regime, fed by monsoon rain and snowmelt and flowing all year.

A candidate who has never met the Rupen or the Machchhu can still answer this. Three names cluster in Gujarat and Rajasthan and one belongs to a valley in the north-east that shares a name with a well-known Assam district. The test is regional placement, not hydrology. It is also worth keeping the two Banas rivers apart — the Gujarat one drains to the Rann, the Rajasthan one joins the Chambal.

• The Barak rises in Manipur, flows through the Barak valley of Assam and becomes the Surma and Kushiyara in Bangladesh, feeding the Meghna.
• The Rupen, the north Gujarat Banas and the Machchhu all drain inland to the Rann of Kachchh.
• The Luni is the best-known desert river, rising in the Aravallis and turning saline as it approaches the Rann.
• Inland drainage means these rivers do not reach the sea; their water is lost to evaporation and seepage.
• The Barak valley is one of the wetter parts of India, which places the Barak outside any desert classification.

• Confusing the Gujarat Banas with the Rajasthan Banas, a Chambal tributary.
• Reading Barak as a western river because of its short, unfamiliar name.

A negative-stem placement item where three obscure names share a region and one familiar name does not.

• practice — not a real PYQ

  The Luni river finally ends in

  • (a)The Arabian Sea at the Gulf of Khambhat
  • (b)The Rann of Kachchh
  • (c)The Sambhar lake
  • (d)The Chambal

  Answer(b) The Rann of Kachchh — the Luni turns saline downstream and is lost in the marshes without reaching the sea.

• practice — not a real PYQ

  The Barak river is a part of which river system?

  • (a)Brahmaputra
  • (b)Meghna
  • (c)Mahanadi
  • (d)Subarnarekha

  Answer(b) Meghna — the Barak becomes the Surma and Kushiyara in Bangladesh and joins the Meghna.