Which one of the following is NOT a tributary of Indus River ?
- (a)Beas
- (b)Ravi
- (c)Chenab
- (d)Tawi
Correct — D, Tawi. School geography gives the Indus a standard set of Himalayan tributaries — the Jhelum, the Chenab, the Ravi, the Beas and the Satluj, the five rivers that give the Punjab its name. Beas, Ravi and Chenab are all on that list, and the Tawi is not. The Tawi is a much smaller river, rising in the Himalaya of the Jammu region and flowing past Jammu city before joining the Chenab; it is therefore a tributary of a tributary, and it does not appear among the rivers named as tributaries of the Indus. It is the odd one out, and the key marks it.
- (a)Beas — The Beas rises near the Rohtang Pass in Himachal Pradesh and is one of the five rivers of the Punjab, listed as a tributary of the Indus. It is the only one of the five that lies wholly within India.
- (b)Ravi — The Ravi rises in the Kangra region of Himachal Pradesh and is likewise one of the five Punjab rivers named as tributaries of the Indus.
- (c)Chenab — The Chenab is the largest of the five, formed by the union of the Chandra and the Bhaga at Tandi in Himachal Pradesh. It carries the waters of the others down to the Indus, and it is unambiguously a tributary.
The Indus rises near Lake Mansarovar in Tibet, enters India through Ladakh, and is joined on its way by the Zaskar, the Shyok, the Nubra and the Hunza in the mountains and by the five Punjab rivers further down. Those five do not each meet the main stream separately. The Beas joins the Satluj; the Ravi and the Jhelum join the Chenab; the Satluj and the Chenab then unite to form the Panjnad, and it is the Panjnad that meets the Indus. The waters of all five are shared between India and Pakistan under the Indus Waters Treaty of 1960, which allots the three eastern rivers — Ravi, Beas and Satluj — to India and the three western ones — Indus, Jhelum and Chenab — largely to Pakistan.
There is a real tension in this item and it is worth naming honestly, because a well-prepared candidate will spot it. On a strict reading of the drainage map the Tawi does belong to the Indus system — it flows into the Chenab, whose water reaches the Indus — so it is not outside the basin. But so does the Beas belong only indirectly, since it flows into the Satluj rather than into the Indus itself. What the question is really testing is membership of the named list that textbooks supply, and on that list the Beas, Ravi and Chenab appear while the Tawi does not. Author and candidate alike should therefore read 'tributary of the Indus' here as 'one of the rivers conventionally named as its tributaries', and the key is sound on that reading. The safest habit for this whole family of questions is to learn the five Punjab rivers as a block, then to learn separately which smaller river joins which of them — the Tawi into the Chenab, the Beas into the Satluj.
- The Indus rises near Lake Mansarovar in Tibet and enters India through Ladakh.
- Its five conventionally named Himalayan tributaries are the Jhelum, Chenab, Ravi, Beas and Satluj.
- The Tawi rises in the Jammu Himalaya, flows past Jammu city and joins the Chenab.
- The Beas joins the Satluj; the Ravi and Jhelum join the Chenab; the Satluj and Chenab unite as the Panjnad.
- Under the Indus Waters Treaty of 1960 the Ravi, Beas and Satluj are allotted to India and the Indus, Jhelum and Chenab largely to Pakistan.
- Assuming every river in a basin counts as a tributary of the master stream; most join another tributary first.
- Mixing up which Punjab river joins which — the Beas goes into the Satluj, not into the Indus directly.
- Confusing the Tawi with the Ravi, which are similar in name but very different in status.
NDA sets Indus-system questions as odd-one-out items like this one, as river-and-tributary pairs, or by naming the river on which a hydro project stands.
Which one of the following rivers does not originate in India ?
- (a) Beas
- (b) Chenab
- (c) Ravi
- (d) Sutlej
Answer(d) Sutlej
The same three rivers as this NDA item's wrong options, tested on where each rises rather than on where each ends. UPSC keys the Satluj as the Tibetan-born one, which is a useful second fact about the same set.
Consider the following pairs: Tributary River – Main River 1. Chambal : Narmada 2. Sone : Yamuna 3. Manas : Brahmaputra Which of the pairs given above is/are correctly matched?
- (a) 1, 2 and 3
- (b) 1 and 2 only
- (c) 2 and 3 only
- (d) 3 only
Answer(d) 3 only
Exactly the trap this item sets — the Chambal and the Sone are real rivers wrongly attached to the wrong master stream, just as the Tawi is a real river of the Indus basin that is not one of the Indus's named tributaries.
River Beas, flowing from Himachal and Punjab, joins the river
- (a) Indus
- (b) Satluj
- (c) Chenab
- (d) Ravi
Answer(b) Satluj
NDA's own key says the Beas joins the Satluj rather than the Indus, yet the 2018 paper counts the Beas as an Indus tributary. Together the two items show that 'tributary of the Indus' in these papers means membership of the standard list, not a direct confluence.
Which one of the following pairs of a river and its tributary is not correctly matched ?
- (a) Godavari : Wainganga
- (b) Cauvery : Bhavani
- (c) Narmada : Amaravati
- (d) Krishna : Bhima
Answer(c) Narmada : Amaravati
The same odd-one-out format applied to peninsular rivers, and set by NDA two years earlier. River-and-tributary pairs are a standing feature of this paper.
- practice — not a real PYQ
The Chenab is formed by the confluence of which two streams?
- (a)Alaknanda and Bhagirathi
- (b)Chandra and Bhaga
- (c)Shyok and Nubra
- (d)Beas and Satluj
Answer(b) Chandra and Bhaga — which meet at Tandi in Himachal Pradesh.
- practice — not a real PYQ
Under the Indus Waters Treaty of 1960, which three rivers were allotted to India?
- (a)Indus, Jhelum and Chenab
- (b)Ravi, Beas and Satluj
- (c)Jhelum, Ravi and Beas
- (d)Chenab, Satluj and Beas
Answer(b) Ravi, Beas and Satluj — the three eastern rivers; the western three go largely to Pakistan.