UPSC Prelims 2002 Q24: Geography – Indian Physical Geography
Which one of the following is NOT a lagoon?
- (a) Ashtamudi lake
- (b) Chilka lake
- (c) Periyar lake
- (d) Pulicat lake
Answer: (c) Periyar lake
Explanation
Water body that is NOT a lagoon
| Water body | Type |
|---|---|
| Chilka (Chilika) lake | Odisha — Asia's largest brackish-water lagoon |
| Pulicat lake | Andhra Pradesh and Tamil Nadu — lagoon behind Sriharikota barrier |
| Ashtamudi lake | Kerala — a lagoon/backwater, a Ramsar site |
| Periyar lake | Kerala — freshwater reservoir formed by the Mullaperiyar dam; not a lagoon |
The question asks which one is NOT a lagoon. A lagoon is a shallow coastal water body cut off from the sea by a sand bar. Chilka, Pulicat and Ashtamudi are coastal lagoons. Periyar lake is an artificial freshwater lake in the Western Ghats, so it is the odd one out.
Answer: (c) Periyar lake.
Why each option is right or wrong
- (a) Incorrect. Ashtamudi is a coastal lagoon, so it is not the answer.
- (b) Incorrect. Chilka is a coastal lagoon, so it is not the answer.
- (c) CORRECT. Periyar is an inland freshwater reservoir, not a lagoon.
- (d) Incorrect. Pulicat is a coastal lagoon, so it is not the answer.
Key point
Lagoon = shallow coastal water separated from the sea by a bar; Chilka, Pulicat, Ashtamudi, Vembanad are examples.
Remember
Periyar lake is a reservoir, not a lagoon.
Common mistakes
- Missing the word NOT and choosing Chilka.
- Believing Periyar is a lagoon because it is in Kerala.
- Forgetting that a lagoon must be on the coast.
Exam tip
Pick the inland or freshwater body; the rest lie on the coast.
Sources
- NCERT Class XI — India: Physical Environment (Drainage)
- Ramsar Convention — Indian sites