NDA (I) 2018 General Ability Test · Question 111 of 150

Correct — C, Indravati. The Indravati belongs to the Godavari system, not the Cauvery. It rises in the Kalahandi hills of Odisha, flows west across the Bastar plateau of Chhattisgarh past Jagdalpur, and joins the Godavari as one of that river's major left-bank tributaries. The other three are all genuine Cauvery tributaries: the Hemavati is the Cauvery's largest tributary and joins it at the Krishna Raja Sagara reservoir in Karnataka; the Arkavati, which flows past Bengaluru's western edge, meets it lower down; and the Amaravati joins in Tamil Nadu, further downstream than the Bhavani and the Noyyal. So the odd river out is the only one that drains east into the Godavari basin instead of south-east into the Cauvery.

• (a)Hemavati — The Hemavati is the largest tributary of the Cauvery. It rises in the Western Ghats of Chikkamagaluru district and joins the main river at Krishna Raja Sagara, alongside the Lakshmana Tirtha.
• (b)Arkavati — The Arkavati is a Cauvery tributary that rises in the Nandi Hills and drains the Bengaluru region, feeding the Hesaraghatta and Tippagondanahalli reservoirs before joining the main river in Karnataka.
• (d)Amravati — The Amaravati, printed here as Amravati, joins the Cauvery in Tamil Nadu downstream of the confluence with the Bhavani and the Noyyal. Its name is the source of a second trap — an NDA paper two years earlier offered the pair 'Narmada : Amaravati' as a river-and-tributary match and marked it wrong for exactly this reason.

The Cauvery rises at Talakaveri in the Brahmagiri hills of Kodagu district, Karnataka, and flows south-east across the Deccan and the Tamil Nadu plain to the Bay of Bengal, building the delta around Thanjavur that made the region a rice bowl. Its main tributaries divide neatly by state — Hemavati, Lakshmana Tirtha, Kabini, Shimsha and Arkavati in Karnataka; Bhavani, Noyyal and Amaravati in Tamil Nadu. The Godavari, India's second-longest river, drains an altogether different basin further north, taking in the Indravati, the Pranahita, the Wainganga, the Manjira and the Penganga.

This is a mismatch item, so the reliable route is to pin down the one river whose basin you can name with confidence rather than to verify all four. The Indravati is easy to fix because it runs through Bastar and gives its name to the Indravati National Park in southern Chhattisgarh, and Chhattisgarh has nothing to do with the Cauvery. A second useful habit is to notice the name traps that examiners exploit in this region — Amaravati is both a Cauvery tributary and a Krishna-side town that is now a capital city of Andhra Pradesh, and Bhavani names both a Cauvery tributary and the town at its confluence. Nothing about a name tells you which basin it belongs to; only the geography does.

• Cauvery tributaries include the Hemavati, its largest, along with the Lakshmana Tirtha, Kabini, Shimsha and Arkavati in Karnataka and the Bhavani, Noyyal and Amaravati in Tamil Nadu.
• The Indravati is a left-bank tributary of the Godavari, rising in Odisha and flowing west through Bastar in Chhattisgarh.
• The Cauvery rises at Talakaveri in Kodagu district, Karnataka, and reaches the Bay of Bengal through its Tamil Nadu delta.
• The Hemavati and the Lakshmana Tirtha join the Cauvery at the Krishna Raja Sagara reservoir.

• Matching rivers by the sound of their names rather than by their basins.
• Confusing the Amaravati tributary of the Cauvery with the town of Amaravati in Andhra Pradesh.
• Forgetting that the Indravati flows west across Bastar even though it rises in Odisha.

River-and-tributary mismatch items recur in both NDA and UPSC, usually with three genuine pairs and one river borrowed from a neighbouring basin.

• practice — not a real PYQ

  The Indravati river is a tributary of the

  • (a)Cauvery
  • (b)Krishna
  • (c)Godavari
  • (d)Mahanadi

  Answer(c) Godavari — it is a major left-bank tributary, flowing west through Bastar to meet the main river.

• practice — not a real PYQ

  The largest tributary of the Cauvery, which joins it at the Krishna Raja Sagara reservoir, is the

  • (a)Bhavani
  • (b)Hemavati
  • (c)Noyyal
  • (d)Shimsha

  Answer(b) Hemavati — it rises in the Western Ghats of Chikkamagaluru district and joins at Krishna Raja Sagara.