CDS Geography · Indian Geography — Physical Features
Lakes and Waterfalls
How lakes form and one example of each kind, which state each well-known lake is in, the waterfalls CDS has asked, and the ways of harvesting rain.
Why this matters
Twelve CDS questions from 2017 to 2024: 1 EASY, 8 MODERATE, 3 HARD. Lonar lake alone has come up three times, and most of the rest are match-the-lake-to-its-state items.
Concept 1 of 4: Lakes by how they formed
A lake is water sitting in a hollow, so the question is always what made the hollow. Earth movements, a meteorite, a glacier, a landslide, a sand bar on the coast or an old river bend can each make one. Learn one Indian example for each.
Definition
The kinds of lake:
- Tectonic: a hollow made by earth movements. Bhimtal (Kumaon), Wular (Kashmir).
- Crater: Lonar (Maharashtra), made by a meteorite hitting the Deccan basalt.
- Glacial: Gangabal (Kashmir), held back by a glacier's moraine.
- Landslide: Gohna (Garhwal), made when a landslide blocked a river in 1893.
- Lagoon: water cut off behind a sand bar on the coast. Chilika (Odisha), Ashtamudi and Vembanad (Kerala).
- Fluvial (oxbow): an old river bend cut off from the river. Purbasthali (West Bengal).
Wular is India's largest freshwater lake; Chilika is its largest lagoon and is brackish.
| Kind | Example | Where |
|---|---|---|
| Tectonic | Bhimtal; Wular | Uttarakhand; Kashmir |
| Crater | Lonar | MaharashtraQ CDS 2020 (II): Lonar's rocks resemble samples from the Moon. |
| Glacial | Gangabal | Kashmir |
| Landslide | Gohna | Garhwal, UttarakhandQ CDS 2017 (II): Bhimtal tectonic, Ashtamudi lagoon, Gohna landslide, Lonar crater. |
| Lagoon | Chilika; Ashtamudi; Vembanad | Odisha; Kerala; Kerala |
| Fluvial (oxbow) | Purbasthali | West Bengal |
| Largest freshwater lake | Wular | KashmirQ CDS 2019 (II): Wular, not Chilika, which is brackish. |
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
CDS · 2019 · CDS (I) 2019 — General Knowledge · Q97Moderate
Example 1 · Indian Geography — Physical Features · Lakes and Waterfalls
Match List-I with List-II and select the correct answer using the code given below the Lists :
Code :
| List-I (Type of Lake) | List-II (Example) |
|---|---|
| A. Tectonic | 1. Lonar Lake |
| B. Crater | 2. Gangabal Lake |
| C. Glacial | 3. Purbasthali Lake |
| D. Fluvial | 4. Bhimtal Lake |
Chilika is the biggest lagoon, not the biggest freshwater lake
Chilika is India's largest lagoon, and its water is brackish. The largest freshwater lake is Wular in Kashmir.
Lonar is a meteorite crater
Lonar lies in a crater made by a meteorite, not by a volcano, even though it sits in volcanic Deccan basalt.
Concept 2 of 4: Lakes by state
Most lake questions are a map question in disguise: name the state. Group the lakes by region, Himalaya, north-east, east coast and south, and the options sort themselves.
Definition
By region:
- Ladakh: Pangong Tso, Tso Moriri, Tso Kar.
- Himachal Pradesh: Khajjiar (near Dalhousie), Ghepan Ghat glacial lake (Lahaul and Spiti).
- Sikkim: Tsomgo (Changu), Khecheopalri.
- North-east: Loktak (Manipur), Barapani or Umiam (Meghalaya).
- East coast: Kolleru (Andhra Pradesh), Pulicat (Andhra Pradesh and Tamil Nadu), Kaliveli (Tamil Nadu).
- Kerala: Vembanad, Ashtamudi.
- Gujarat: Panchmuli, beside the Statue of Unity.
| Lake | State or UT |
|---|---|
| Pangong Tso, Tso Moriri, Tso Kar | LadakhQ CDS 2017 (II): Tsomgo was the one lake in the list that is not in Ladakh. |
| Tsomgo (Changu) | SikkimQ |
| Khecheopalri | SikkimQ CDS 2022 (I): Kaliveli Tamil Nadu, Khajjiar Himachal, Khecheopalri Sikkim, Vembanad Kerala. |
| Khajjiar | Himachal Pradesh |
| Ghepan Ghat glacial lake | Himachal PradeshQ |
| Loktak | Manipur |
| Barapani (Umiam) | Meghalaya |
| Kolleru | Andhra Pradesh |
| Pulicat | Andhra Pradesh and Tamil Nadu |
| Kaliveli | Tamil Nadu |
| Vembanad | Kerala |
| Panchmuli | Gujarat, beside the Statue of UnityQ |
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
CDS · 2023 · CDS (I) 2023 — General Knowledge · Q17Moderate
Example 2 · Indian Geography — Physical Features · Lakes and Waterfalls
Rani told her friends that last year she did boating in four different lakes, namely, Loktak, Barapani, Kolleru and Pulicat. Which of the following States did she visit?
Not every Tso is in Ladakh
Tso means lake in the Tibetan languages, so it turns up outside Ladakh too. Tsomgo is in Sikkim.
Kolleru is in Andhra Pradesh
Kolleru is a freshwater lake between the Godavari and Krishna deltas in Andhra Pradesh, not in Kerala or Tamil Nadu.
Concept 3 of 4: Waterfalls
Most of India's famous waterfalls are in the Western Ghats and the southern hills, where rivers drop off the edge of the plateau. Learn each fall with its state; the river helps you place it.
Definition
The falls to know:
- Karnataka: Jog (on the Sharavati), Barkana.
- Goa: Dudhsagar, on the Mandovi.
- Odisha: Duduma, on the Machkund.
- Tamil Nadu: Kiliyur (near Yercaud), Hogenakkal (on the Kaveri).
- Kerala: Athirappilly.
- Meghalaya: Nohkalikai, near Cherrapunji.
| Waterfall | State | River or place |
|---|---|---|
| Jog | Karnataka | Sharavati river |
| Barkana | Karnataka | Western Ghats |
| Dudhsagar | Goa | Mandovi river |
| Duduma | Odisha | Machkund river |
| Kiliyur | Tamil Nadu | Near Yercaud |
| Hogenakkal | Tamil Nadu | Kaveri river |
| Athirappilly | Kerala | Chalakudy river |
| Nohkalikai | Meghalaya | Near Cherrapunji |
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
CDS · 2022 · CDS (I) 2022 — General Knowledge · Q73Hard
Example 3 · Indian Geography — Physical Features · Lakes and Waterfalls
Match List I with List II and select the correct answer using the code given below the lists :
Code :
| List I (Waterfall) | List II (State) |
|---|---|
| A. Barkana | 1. Tamil Nadu |
| B. Dudhsagar | 2. Odisha |
| C. Duduma | 3. Karnataka |
| D. Kiliyur | 4. Goa |
Dudhsagar is in Goa
Dudhsagar lies on the Goa side of the Karnataka border, on the Mandovi. In the options it belongs to Goa, not Karnataka.
Concept 4 of 4: Rainwater harvesting
In a city the rain falls on roofs and roads, so harvesting means leading roof water underground. In the countryside the aim is to slow water running down slopes and streams. The method tells you where it belongs.
Definition
City methods:
- Rooftop harvesting into a recharge pit, recharge trench or recharge well, which send the water down to refill the groundwater.
Rural and traditional methods:
- Gully plug and check dam: small walls across gullies and streams on slopes.
- Guls or kuls: diversion channels of the Western Himalaya.
- Khadins and johads: field ponds of Rajasthan.
- Tankas: underground tanks under the roof in western Rajasthan.
- Bamboo drip irrigation: Meghalaya.
| Method | Where it is used |
|---|---|
| Rooftop recharge pit | Cities |
| Recharge trench | Cities |
| Recharge well | Cities |
| Gully plug | Hill slopes in the countryside |
| Check dam | Streams in the countryside |
| Guls or kuls | Western Himalaya |
| Khadins, johads, tankas | Rajasthan |
| Bamboo drip irrigation | Meghalaya |
Practice this conceptself-check · 3 quick reps
The same idea in a real exam question:
CDS · 2019 · CDS (I) 2019 — General Knowledge · Q76Moderate
Example 4 · Indian Geography — Physical Features · Lakes and Waterfalls
Which one of the following methods is not suitable for urban rainwater harvesting?
A gully plug is a rural method
A gully plug is a small wall across a gully on a hill slope. Cities harvest rain through rooftop collection feeding recharge pits, trenches and wells.
Summary — formulas & gotchas at a glance
A revision cheat-sheet for the formulas and gotchas above. Click any concept name to jump back to its full explanation.
Reference tables (4)
Lakes by how they formed7 rows
| Kind | Example | Where |
|---|---|---|
| Tectonic | Bhimtal; Wular | Uttarakhand; Kashmir |
| Crater | Lonar | MaharashtraQ CDS 2020 (II): Lonar's rocks resemble samples from the Moon. |
| Glacial | Gangabal | Kashmir |
| Landslide | Gohna | Garhwal, UttarakhandQ CDS 2017 (II): Bhimtal tectonic, Ashtamudi lagoon, Gohna landslide, Lonar crater. |
| Lagoon | Chilika; Ashtamudi; Vembanad | Odisha; Kerala; Kerala |
| Fluvial (oxbow) | Purbasthali | West Bengal |
| Largest freshwater lake | Wular | KashmirQ CDS 2019 (II): Wular, not Chilika, which is brackish. |
Lakes by state12 rows
| Lake | State or UT |
|---|---|
| Pangong Tso, Tso Moriri, Tso Kar | LadakhQ CDS 2017 (II): Tsomgo was the one lake in the list that is not in Ladakh. |
| Tsomgo (Changu) | SikkimQ |
| Khecheopalri | SikkimQ CDS 2022 (I): Kaliveli Tamil Nadu, Khajjiar Himachal, Khecheopalri Sikkim, Vembanad Kerala. |
| Khajjiar | Himachal Pradesh |
| Ghepan Ghat glacial lake | Himachal PradeshQ |
| Loktak | Manipur |
| Barapani (Umiam) | Meghalaya |
| Kolleru | Andhra Pradesh |
| Pulicat | Andhra Pradesh and Tamil Nadu |
| Kaliveli | Tamil Nadu |
| Vembanad | Kerala |
| Panchmuli | Gujarat, beside the Statue of UnityQ |
Waterfalls8 rows
| Waterfall | State | River or place |
|---|---|---|
| Jog | Karnataka | Sharavati river |
| Barkana | Karnataka | Western Ghats |
| Dudhsagar | Goa | Mandovi river |
| Duduma | Odisha | Machkund river |
| Kiliyur | Tamil Nadu | Near Yercaud |
| Hogenakkal | Tamil Nadu | Kaveri river |
| Athirappilly | Kerala | Chalakudy river |
| Nohkalikai | Meghalaya | Near Cherrapunji |
Rainwater harvesting8 rows
| Method | Where it is used |
|---|---|
| Rooftop recharge pit | Cities |
| Recharge trench | Cities |
| Recharge well | Cities |
| Gully plug | Hill slopes in the countryside |
| Check dam | Streams in the countryside |
| Guls or kuls | Western Himalaya |
| Khadins, johads, tankas | Rajasthan |
| Bamboo drip irrigation | Meghalaya |
Watch out for (6)
- Chilika is the biggest lagoon, not the biggest freshwater lake→ Lakes by how they formed
- Lonar is a meteorite crater→ Lakes by how they formed
- Not every Tso is in Ladakh→ Lakes by state
- Kolleru is in Andhra Pradesh→ Lakes by state
- Dudhsagar is in Goa→ Waterfalls
- A gully plug is a rural method→ Rainwater harvesting
Test yourself on Indian Geography — Physical Features
20 past CDS questions from this chapter, timed at 20 minutes and marked the way the exam marks it. You see your score and every answer the moment you finish. Free to start.