The drainage system refers to the network of rivers and streams that drain water from the land into seas, oceans, or lakes. In India, the drainage pattern is influenced by relief, geological structure, climate, and slope of land. Rivers are extremely important for agriculture, drinking water, hydroelectric power, transportation, and cultural activities.
NDA & CDS 1 2026 Exam GK – Indian Geography – Drainage
Indian rivers are broadly classified into two major groups:
- Himalayan Rivers
- Peninsular Rivers
1. Himalayan Drainage System
The Himalayan rivers originate from the Himalayan glaciers and receive water from snowmelt and rainfall, making them perennial (flow throughout the year).
Major Himalayan River Systems
1. Indus River System
- Originates near Lake Mansarovar in Tibet.
- Major tributaries: Jhelum, Chenab, Ravi, Beas, and Sutlej.
- The river flows through India and Pakistan before draining into the Arabian Sea.
2. Ganga River System
- Originates from the Gangotri Glacier in Uttarakhand as the Bhagirathi River.
- At Devprayag, Bhagirathi meets Alaknanda to form the Ganga.
- Major tributaries: Yamuna, Ghaghara, Gandak, Kosi, Son.
- Forms the largest delta in the world – the Sundarbans Delta before entering the Bay of Bengal.
3. Brahmaputra River System
- Originates from the Chemayungdung Glacier near Lake Mansarovar in Tibet where it is called Tsangpo.
- Enters India through Arunachal Pradesh as Siang/Dihang and later becomes Brahmaputra in Assam.
- Known for large braided channels and frequent floods.
Characteristics of Himalayan Rivers
- Perennial rivers
- Form deep gorges in mountains
- Carry large amounts of sediments
- Form large floodplains and deltas
2. Peninsular Drainage System
The Peninsular rivers originate from plateaus and hills of the Peninsular Plateau. These rivers mainly depend on monsoon rainfall, so most of them are seasonal.
Major Peninsular Rivers
1. Godavari River
- Known as the “Dakshin Ganga”.
- Originates from Trimbak Hills in Maharashtra.
- Longest river of Peninsular India.
- Drains into the Bay of Bengal.
2. Krishna River
- Originates near Mahabaleshwar in Maharashtra.
- Major tributaries: Tungabhadra, Bhima, Ghataprabha.
- Empties into the Bay of Bengal.
3. Kaveri River
- Originates from Brahmagiri Hills in Karnataka.
- Important for irrigation in Karnataka and Tamil Nadu.
- Forms a fertile delta in Tamil Nadu.
4. Narmada River
- Originates from Amarkantak Plateau in Madhya Pradesh.
- Flows westward into the Arabian Sea.
- Flows through a rift valley.
5. Tapi (Tapti) River
- Also flows westward from Satpura Range into the Arabian Sea.
Characteristics of Peninsular Rivers
- Mostly seasonal
- Flow through broad valleys
- Have less water volume compared to Himalayan rivers
- Less prone to floods
Drainage Patterns in India
Different drainage patterns develop depending on geological structure.
- Dendritic Pattern – Tree-like branching pattern (common in northern plains).
- Trellis Pattern – Parallel main rivers with tributaries joining at right angles.
- Radial Pattern – Rivers flow outward from a central peak.
- Rectangular Pattern – Rivers follow fault lines forming right-angle bends.
Importance of Rivers in India
- Irrigation and agriculture
- Hydroelectric power generation
- Drinking water supply
- Transportation and trade
- Religious and cultural significance
MCQs – Indian Geography: Drainage System (NDA/CDS Level)
1. The river known as “Dakshin Ganga” is:
A. Krishna
B. Godavari
C. Kaveri
D. Narmada
Answer: B
Explanation: Godavari is called Dakshin Ganga because it is the longest river of Peninsular India.
2. The Indus River originates near:
A. Gangotri Glacier
B. Lake Mansarovar
C. Amarkantak Plateau
D. Brahmagiri Hills
Answer: B
Explanation: Indus originates near Lake Mansarovar in Tibet.
3. Which river forms the world’s largest delta?
A. Indus
B. Godavari
C. Ganga-Brahmaputra
D. Krishna
Answer: C
Explanation: The Sundarbans Delta formed by Ganga and Brahmaputra is the largest delta in the world.
4. Which river flows through a rift valley?
A. Godavari
B. Krishna
C. Narmada
D. Mahanadi
Answer: C
Explanation: Narmada flows through a rift valley between Vindhya and Satpura ranges.
5. Which of the following is NOT a tributary of the Ganga?
A. Yamuna
B. Gandak
C. Kosi
D. Beas
Answer: D
Explanation: Beas is a tributary of the Indus River system.
6. The Brahmaputra is known as Tsangpo in:
A. India
B. Nepal
C. Tibet
D. Bhutan
Answer: C
Explanation: In Tibet, the Brahmaputra River is called Tsangpo.
7. Which river originates from the Brahmagiri Hills?
A. Krishna
B. Kaveri
C. Godavari
D. Tapi
Answer: B
8. The largest river basin in India is:
A. Indus Basin
B. Godavari Basin
C. Ganga Basin
D. Krishna Basin
Answer: C
9. Which of the following rivers flows westward?
A. Krishna
B. Godavari
C. Narmada
D. Mahanadi
Answer: C
10. The drainage pattern resembling branches of a tree is called:
A. Radial
B. Trellis
C. Rectangular
D. Dendritic
Answer: D
