UPSC Prelims 2004 Q70: Geography – Indian Rivers & Water Resources
Assertion (A): West - flowing rivers of Peninsular India have no deltas.
Reason (R): These rivers do not carry any alluvial sediment.
- (a) Both A and R are individually true and R is the correct explanation of A
- (b) Both A and R are individually true but R is not the correct explanation of A
- (c) A is true but R is false
- (d) A is false but R is true
Answer: (c) A is true but R is false
Explanation
Deltas of west-flowing peninsular rivers
| Part | Verdict |
|---|---|
| A. West-flowing rivers have no deltas | True — they form estuaries |
| R. They carry no alluvial sediment | False: they do carry sediment, but flow in a rift valley, are short and fast, and drain into the sea through narrow estuaries |
A is true and R is false: the west-flowing rivers, like the Narmada and Tapi, do carry sediment, but their steep, short courses and the rift-valley mouths give estuaries instead of deltas.
Answer: (c) A is true but R is false.
Why each option is right or wrong
- (a) Incorrect. R is false, so it cannot be the explanation.
- (b) Incorrect. R is not true, as these rivers carry sediment.
- (c) CORRECT. A is true as they end in estuaries, but R is false as they do carry alluvium.
- (d) Incorrect. A is true, as they have estuaries.
Key point
Narmada and Tapi: estuaries; Mahanadi, Godavari, Krishna, Cauvery: deltas.
Remember
West-flowing rivers form estuaries, not deltas.
Common mistakes
- Believing these rivers carry no sediment.
- Mixing estuary and delta formation.
- Forgetting the strong tidal action on the west coast.
Exam tip
West coast: narrow coastal plains, estuaries; east coast: broad plains, deltas.
Sources
- NCERT Class XI Geography — Drainage System
- Central Water Commission and National Remote Sensing Centre — India-WRIS: River Basin Atlas (Narmada and Tapi basins)