UPSC Prelims 2021 Q55: Rivers of the Eastern Ghats — Explained
Consider the following rivers:
1. Brahmani
2. Nagavali
3. Subarnarekha
4. Vamsadhara
Which of the above rise from the Eastern Ghats?
- 1 and 2
- 2 and 4
- 3 and 4
- 1 and 3
Answer: (b) 2 and 4
Statement-wise explanation
- 1: incorrect — The Brahmani does not rise in the Eastern Ghats. Its upper course, the South Koel, rises near Nagri village in Ranchi district, Jharkhand, at about 600 m on the Chota Nagpur Plateau. It is joined by the Sankh near Vedavyas, close to Rourkela in Odisha. Below that confluence the river is called the Brahmani. The Central Water Commission gives its total length as about 799 km.
- 2: correct — The Nagavali (also called the Langulya) rises near Lakhbahal in Kalahandi district, Odisha, at about 1,300 m. These are Eastern Ghats hills. The Central Water Commission gives its length as 256 km. It flows south-east through Odisha and Andhra Pradesh to the Bay of Bengal.
- 3: incorrect — The Subarnarekha rises near Nagri village in Ranchi district, Jharkhand, at about 600 m. That is the Chota Nagpur Plateau, not the Eastern Ghats. It flows about 395 km through Jharkhand, Odisha and West Bengal to the Bay of Bengal.
- 4: correct — The Vamsadhara rises near Lanjigarh in Kalahandi district, Odisha, in the Eastern Ghats. It runs about 254 km and enters the Bay of Bengal at Kalingapatnam in Andhra Pradesh. Its waters are shared by Odisha and Andhra Pradesh. The Vansadhara Water Disputes Tribunal was set up in 2010 to settle that dispute.
How to eliminate
Start with the river you are surest of. The Subarnarekha is the river of Ranchi and Jamshedpur, so it rises on the Chota Nagpur Plateau. That rules out every option that includes statement 3, leaving two options: 1 and 2, or 2 and 4. Both contain the Nagavali, so you only need to decide between the Brahmani and the Vamsadhara. The Brahmani forms at Rourkela, where two Chota Nagpur streams, the Sankh and the South Koel, meet. So it is not an Eastern Ghats river, and the answer is 2 and 4. A rule of thumb that helps here: rivers that reach the sea in north Odisha or West Bengal (Subarnarekha, Brahmani) mostly come down from the Chota Nagpur Plateau. Rivers that reach the sea in south Odisha or north Andhra Pradesh (Vamsadhara, Nagavali, Rushikulya) rise in the Eastern Ghats of Kalahandi, Kandhamal and Koraput. The question has no absolute words to exploit. What you need to remember is where the rivers rise: the Vamsadhara and Nagavali in Kalahandi, the Brahmani and Subarnarekha near Ranchi.
Know more
Peninsular rivers and where they rise
The Peninsular rivers that drain into the Bay of Bengal come from three different highlands:
- The Western Ghats: the big east-flowing rivers (Godavari, Krishna, Kaveri). They cross the whole plateau because the Peninsula tilts towards the east.
- The Chota Nagpur Plateau and the Chhattisgarh highlands: the rivers of north Odisha and West Bengal (Subarnarekha, Brahmani; the Mahanadi rises in Chhattisgarh).
- The Eastern Ghats: shorter, swift rivers of south Odisha and north Andhra Pradesh (Vamsadhara, Nagavali, Rushikulya).
The Eastern Ghats are low, broken hills, not a continuous wall. They are cut through by the larger rivers, and they are the source of only short coastal rivers. That is why so few major rivers rise there.
| River | Where it rises (CWC) | Highland | Length |
|---|---|---|---|
| Subarnarekha | Near Nagri, Ranchi district, Jharkhand (600 m) | Chota Nagpur Plateau | ~395 km |
| Brahmani (as South Koel) | Near Nagri, Ranchi district, Jharkhand (~600 m) | Chota Nagpur Plateau | ~799 km |
| Baitarani | Keonjhar hills, Odisha (~900 m) | North Odisha highlands | 355 km |
| Mahanadi | Near Pharsiya, Chhattisgarh (~422 m) | Chhattisgarh highlands | ~851 km |
| Rushikulya | Near Matabarhi, Phulbani (Kandhamal), Odisha (~1,000 m) | Eastern Ghats | — |
| Vamsadhara | Near Lanjigarh, Kalahandi, Odisha | Eastern Ghats | ~254 km |
| Nagavali | Near Lakhbahal, Kalahandi, Odisha (~1,300 m) | Eastern Ghats | 256 km |
Points to remember
- The Subarnarekha and the South Koel (the upper Brahmani) both rise near the same Nagri area of Ranchi district.
- The Vamsadhara and the Nagavali flow from Odisha into Andhra Pradesh, so they are inter-state rivers. The Vamsadhara is the subject of a water-sharing tribunal set up in 2010.
- Kalahandi, Rayagada and Koraput lie in the Eastern Ghats and hold bauxite hills such as Niyamgiri near Lanjigarh. Questions on the Vamsadhara and Nagavali often overlap with mining and tribal-rights news from this belt.
NCERT Concepts to Revise
- Eastern Ghats: The question asks which rivers rise in these broken hills along the Odisha–Andhra coast, so you need to know where they run.
- East-flowing rivers of the Peninsula: Places these four smaller rivers alongside the big east-flowing rivers that also end in the Bay of Bengal.
- Western Ghats: Helps you avoid confusing the source of the large east-flowing rivers with the Eastern Ghats.