CDS Geography · Indian Geography — Physical Features
River Systems
The Indus, Ganga and Brahmaputra systems with their tributaries and projects, and the rivers of the peninsula with how they differ from Himalayan rivers.
Why this matters
Twenty CDS questions from 2016 to 2026, the biggest page of the chapter: 3 EASY, 12 MODERATE, 5 HARD, and nine of them since 2023. The favourite shape is a tributary question: which river joins which, and in what order.
Concept 1 of 4: The Indus system
The Indus rises in Tibet, crosses Ladakh and flows into Pakistan. Five rivers of Punjab feed it from the east. Learn them from west to east, Jhelum, Chenab, Ravi, Beas, Satluj, and hang each dam on its river.
Definition
The system:
- The Indus rises in Tibet near Lake Mansarovar and flows through Ladakh into Pakistan.
- Its five eastern tributaries, west to east: Jhelum, Chenab, Ravi, Beas, Satluj.
- The Satluj enters India at Shipki La; the Bhakra Nangal dam stands on it.
- The Chenab carries the Salal project at Reasi in Jammu and Kashmir.
- From the north the Indus gets the Gilgit and Hunza (Karakoram); in Ladakh the Zaskar joins it.
- From the west, the Gomal, Kurram and Kabul come from the Afghan hills (the Sulaiman range), not from the Himalaya.
- In India the Indus basin covers Ladakh, Jammu and Kashmir, Himachal Pradesh, Punjab, Haryana and Rajasthan.
| River | What to remember |
|---|---|
| Jhelum | Flows through Wular lake in the Kashmir valley |
| Chenab | Salal project at ReasiQ CDS 2025 (I): Salal is on the Chenab, not the Jhelum, Nubra or Shyok. |
| Ravi | The middle one of the five Punjab rivers |
| Beas | Joins the Satluj at Harike |
| Satluj | Easternmost; enters at Shipki La; Bhakra Nangal dam |
| Gomal | Rises in the Sulaiman range on the Afghan border, not in the HimalayaQ CDS 2025 (I): the odd one out against the Gilgit, Hunza and Zaskar. |
| Indus basin in India | Ladakh, Jammu and Kashmir, Himachal Pradesh, Punjab, Haryana, RajasthanQ |
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
CDS · 2021 · CDS (I) 2021 — General Knowledge · Q41Easy
Example 1 · Indian Geography — Physical Features · River Systems
Which one of the following tributaries of river Indus feeds the canal system of the Bhakra Nangal Project ?
Bhakra is on the Satluj, Salal on the Chenab
Bhakra Nangal is on the Satluj; Salal is on the Chenab. The Jhelum and the Beas carry other projects, so match the dam to its own river.
Concept 2 of 4: The Ganga system
The Ganga collects rivers from both sides as it flows east. From the Himalaya on its left come the Ramganga, Gomti, Ghaghara, Gandak and Kosi; from the peninsula on its right come the Yamuna and the Son. Many peninsular rivers reach the Ganga only through the Yamuna.
Definition
Key points:
- Right bank (from the south): the Yamuna at Prayagraj, which brings the Chambal, Betwa and Ken; and the Son, which joins the Ganga directly, near Patna.
- Left bank (from the Himalaya), west to east: Ramganga, Gomti, Ghaghara (which has collected the Sharda), Gandak, Kosi, Mahananda.
- Cities on the Ganga, west to east: Kanpur, Prayagraj, Varanasi, Patna, Bhagalpur.
- The basin reaches Himachal Pradesh (Yamuna headwaters), Rajasthan (Chambal and Banas) and Chhattisgarh (through the Son).
- Bhopal is not a river city: it grew around its lakes.
| Tributary | Bank | Where it joins |
|---|---|---|
| Yamuna | Right | Prayagraj |
| Son | Right | Directly, near Patna |
| Gomti | Left | Near GhazipurQ CDS 2018 (I): east to west the order is Kosi, Gandak, Ghaghara, Gomti. |
| Ghaghara | Left | Near Chhapra; the Sharda flows into it first |
| Gandak | Left | Hajipur, opposite Patna |
| Kosi | Left | Near Kursela in Bihar |
| Mahananda | Left | West Bengal, the last big left-bank tributaryQ CDS 2016 (II): the Teesta was the river that does not join the Ganga. |
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
CDS · 2020 · CDS (I) 2020 — General Knowledge · Q41Moderate
Example 2 · Indian Geography — Physical Features · River Systems
Which one of the following rivers joins Ganga directly?
The Teesta is not a Ganga river
The Teesta rises in Sikkim and joins the Brahmaputra. The Son, the Mahananda and the Sharda (through the Ghaghara) all belong to the Ganga.
Chambal, Betwa and Ken go through the Yamuna
The Chambal, Betwa and Ken are tributaries of the Yamuna, so they reach the Ganga only through it. The Son is the peninsular river that joins the Ganga directly.
Concept 3 of 4: The Brahmaputra and the Barak
One river, four names. It rises in Tibet as the Tsangpo, bends sharply round the Namcha Barwa massif, enters Arunachal Pradesh as the Siang or Dihang, becomes the Brahmaputra in Assam and the Jamuna in Bangladesh. The Barak is a separate river of the south, the head of the Meghna.
Definition
The names in order:
- Tsangpo in Tibet; it takes a U-turn round Namcha Barwa.
- Siang or Dihang in Arunachal Pradesh.
- Brahmaputra in Assam, after the Dibang and the Lohit join.
- Jamuna in Bangladesh.
Tributaries:
- North bank: Subansiri, Manas, Puthimari.
- South bank: Dhansiri, Dikhow.
- The Teesta of Sikkim joins it in Bangladesh.
- The Barak rises in the hills of Manipur and is the head stream of the Meghna.
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
CDS · 2019 · CDS (II) 2019 — General Knowledge · Q28Easy
Example 3 · Indian Geography — Physical Features · River Systems
Which one of the following rivers takes a 'U' turn at Namcha Barwa and enters India?
The Barak rises in Manipur
The Barak, head stream of the Meghna, rises in the hills of Manipur, not Meghalaya. CDS 2024 (II) used Meghalaya as the false statement.
Concept 4 of 4: Peninsular rivers
Himalayan rivers are young and fed by snow as well as rain, so they flow all year. Peninsular rivers are old and fed by rain alone, so many shrink in the dry season. Most peninsular rivers run east to the Bay of Bengal because the plateau tilts that way; the Narmada and the Tapi are the big exceptions.
Definition
Himalayan and peninsular rivers:
- Himalayan: perennial (snow and rain), still cutting deep gorges; in their long courses they show youth in the hills, maturity on the plains and old age in the delta.
- Peninsular: seasonal (rain only), flowing on an old, stable block; they have reached maturity and have broad, shallow valleys.
East-flowing: Mahanadi, Godavari, Krishna, Kaveri (deltas on the Bay of Bengal). West-flowing: Narmada (rift valley between the Vindhya and the Satpura) and Tapi; they form estuaries, not deltas. Inland: the Luni of Rajasthan ends in the Rann of Kachchh; the Ghaggar is lost in the Rajasthan desert.
| River | Flows into | Fact |
|---|---|---|
| Mahanadi | Bay of Bengal | Rises in Chhattisgarh |
| Godavari | Bay of Bengal | The largest peninsular river, called the Dakshin Ganga |
| Krishna | Bay of Bengal | With the Tungabhadra it encloses the Raichur doab, between Gulbarga and HampiQ |
| Kaveri | Bay of Bengal | Main tributaries Kabini, Bhavani and AmaravatiQ |
| Narmada | Arabian Sea | Flows west in a rift valley between the Vindhya and the SatpuraQ CDS 2018 (II): the west-flowing river against the Mahanadi, Godavari and Krishna. |
| Tapi | Arabian Sea | Flows west, south of the Satpura |
| Luni | Rann of Kachchh | Tributaries Khari, Sukri and JawaiQ CDS 2018 (II): the Banas is a Chambal tributary, not a Luni one. |
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
CDS · 2017 · CDS (II) 2017 — General Knowledge · Q100Moderate
Example 4 · Indian Geography — Physical Features · River Systems
Which of the following statements is/are correct?
1. Himalayan rivers have their origin in the snow-covered areas, hence are dry in winter season.
2. Rivers of the Peninsular Plateau have reached maturity.
3. Himalayan rivers depict all the three stages of normal cycle of erosion.
Select the correct answer using the code given below.
Only two big rivers flow west
The Mahanadi, Godavari, Krishna and Kaveri flow east to the Bay of Bengal. The Narmada and the Tapi are the large west-flowing rivers.
Snow keeps Himalayan rivers flowing
Because they start in snowfields, Himalayan rivers are perennial: they do not dry up in winter. It is the rain-fed peninsular rivers that shrink in the dry season.
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)
The Indus system7 rows
| River | What to remember |
|---|---|
| Jhelum | Flows through Wular lake in the Kashmir valley |
| Chenab | Salal project at ReasiQ CDS 2025 (I): Salal is on the Chenab, not the Jhelum, Nubra or Shyok. |
| Ravi | The middle one of the five Punjab rivers |
| Beas | Joins the Satluj at Harike |
| Satluj | Easternmost; enters at Shipki La; Bhakra Nangal dam |
| Gomal | Rises in the Sulaiman range on the Afghan border, not in the HimalayaQ CDS 2025 (I): the odd one out against the Gilgit, Hunza and Zaskar. |
| Indus basin in India | Ladakh, Jammu and Kashmir, Himachal Pradesh, Punjab, Haryana, RajasthanQ |
The Ganga system7 rows
| Tributary | Bank | Where it joins |
|---|---|---|
| Yamuna | Right | Prayagraj |
| Son | Right | Directly, near Patna |
| Gomti | Left | Near GhazipurQ CDS 2018 (I): east to west the order is Kosi, Gandak, Ghaghara, Gomti. |
| Ghaghara | Left | Near Chhapra; the Sharda flows into it first |
| Gandak | Left | Hajipur, opposite Patna |
| Kosi | Left | Near Kursela in Bihar |
| Mahananda | Left | West Bengal, the last big left-bank tributaryQ CDS 2016 (II): the Teesta was the river that does not join the Ganga. |
Peninsular rivers7 rows
| River | Flows into | Fact |
|---|---|---|
| Mahanadi | Bay of Bengal | Rises in Chhattisgarh |
| Godavari | Bay of Bengal | The largest peninsular river, called the Dakshin Ganga |
| Krishna | Bay of Bengal | With the Tungabhadra it encloses the Raichur doab, between Gulbarga and HampiQ |
| Kaveri | Bay of Bengal | Main tributaries Kabini, Bhavani and AmaravatiQ |
| Narmada | Arabian Sea | Flows west in a rift valley between the Vindhya and the SatpuraQ CDS 2018 (II): the west-flowing river against the Mahanadi, Godavari and Krishna. |
| Tapi | Arabian Sea | Flows west, south of the Satpura |
| Luni | Rann of Kachchh | Tributaries Khari, Sukri and JawaiQ CDS 2018 (II): the Banas is a Chambal tributary, not a Luni one. |
Watch out for (6)
- Bhakra is on the Satluj, Salal on the Chenab→ The Indus system
- The Teesta is not a Ganga river→ The Ganga system
- Chambal, Betwa and Ken go through the Yamuna→ The Ganga system
- The Barak rises in Manipur→ The Brahmaputra and the Barak
- Only two big rivers flow west→ Peninsular rivers
- Snow keeps Himalayan rivers flowing→ Peninsular rivers
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.