UPSC Prelims 2013 Q15: Geography – Indian Rivers & Water Resources
The Narmada river flows to the west, while most other large peninsular rivers flow to the
east. Why?
1. It occupies a linear rift valley.
2. It flows between the Vindhyas and the Satpuras.
3. The land slopes to the west from Central India.
Select the correct answer using the codes given below:
- (a) 1 only
- (b) 2 and 3 only
- (c) 1 and 3 only
- (d) None
Answer: (a) 1 only
Explanation
Why the Narmada flows west
Most peninsular rivers flow east because the plateau slopes eastward.
The Narmada flows west because it runs along a rift valley.
| Statement | Verdict | Reason |
|---|---|---|
| 1. It occupies a linear rift valley | Correct | A fault trough guides the river westward |
| 2. It flows between the Vindhyas and the Satpuras | True, but not the reason | This only describes its position |
| 3. The land slopes to the west from Central India | Incorrect | The peninsula slopes to the east |
The west-flowing rift rivers:
| River | Rift between |
|---|---|
| Narmada | Vindhya and Satpura ranges |
| Tapi (Tapti) | Satpura and Ajanta ranges |
Features of the Narmada: rises at Amarkantak; forms the Dhuandhar Falls and the Marble Rocks near Jabalpur; ends in an estuary, not a delta.
Answer: (a) 1 only.
Why each option is right or wrong
- (a) CORRECT. The Narmada flows west because it occupies a linear rift valley.
- (b) Incorrect. Statement 2 is not the cause, and statement 3 is false.
- (c) Incorrect. Statement 3 is false; the land slopes east.
- (d) Incorrect. Statement 1 gives the true reason, so 'None' is wrong.
Key point
Narmada and Tapi flow west through rift valleys; the peninsula slopes east; both form estuaries, not deltas.
Remember
Narmada flows west in a rift valley.
Common mistakes
- Treating a true fact (statement 2) as the reason.
- Thinking the land slopes west in central India.
- Forgetting that west-flowing rivers form estuaries.
Exam tip
The question asks 'why'. A true statement that is not the cause must be left out.
Sources
- NCERT Class XI — India: Physical Environment, Ch 3 (Drainage System)
- NCERT Class IX — Contemporary India I, Ch 3 (Drainage)