Drainage Class 9 Geography Chapter 3 Notes | Easy Concept

The chapter Drainage covers topics such as the major rivers of India, drainage patterns, and problems related to river pollution. Class 9 Geography Chapter 3 Notes introduce students to the concept of drainage and explain the various aspects related to it. By studying this chapter, students will be able to understand the significance of drainage in India, the impact of various factors on drainage systems, and the importance of preserving natural water resources.

Drainage | Class 9 Geography Chapter 3 Notes

Drainage refers to the natural or artificial movement of surface water from one place to another.
Natural drainage occurs through the movement of water from higher to lower elevations like Rivers, lakes, and wetlands.
Artificial drainage systems are constructed to manage excess water for agricultural fields, and other areas prone to flooding like channels, pipes, ditches, and culverts.

Drainage Systems in India

India’s major river systems include the Ganges, Brahmaputra, Indus, and Godavari, among others. These rivers play a great role in irrigating agricultural land and providing drinking water to millions of people. The rivers in India are divided into two major groups:

  • The Himalayan rivers
  • The Peninsular rivers
The Himalayan riversThe Peninsular rivers
These rivers are perennial. This flow throughout the year.These rivers are seasonal.
These are steep, fast-flowing, with rapids and waterfalls.These are gentle, slower, wider river channels.
These receive water from the Himalayan mountains.These are dependent on monsoon rainfall.
These originate from the north of the mountain ranges.These originate in the Western Ghats and flow towards the Bay of Bengal.

The Himalayan Rivers

The Himalayan Rivers originate in the Himalayan mountain range. The three major Himalayan rivers in India are the Ganges, Brahmaputra, and Indus.

Class 9 Geography Chapter 3 Notes

1) The Indus River System

  • The Indus River System is one of the major river systems in South Asia.
  • It originates near Mansarovar in the Tibetan plateau and flows through India and Pakistan.
  • It falls into the Arabian Sea.
  • The tributaries of the Indus River are the Jhelum, Chenab, Ravi, Beas, and Sutlej which join the Indus near Mithankot in Pakistan.
  • It is the longest river in Pakistan and the lifeline of the country’s agriculture and economy.

2) The Ganga River System

  • The Ganga River System is one of the most important river systems in India.
  • It originates from the Himalayan mountains to the plains at Haridwar and flows through several states of India.
  • Its source is called the ‘Bhagirathi’, and is fed by the Gangotri Glacier.
  • It is joined by the Alaknanda at Devaprayag in Uttarakhand.
  • It empties into the Bay of Bengal.
  • The system includes the Ganges River and its tributaries, such as the Yamuna, Ghaghara, Gandak, and Kosi.
  • The Ganga River is divided into 2 parts at Farakka in West Bengal.
    i) The Bhagirathi
    ii) Hooghly 
    These meet in the Bay of Bengal at last.
  • The mainstream of Ganga flows southwards into Bangladesh where it is joined by the Brahmaputra.
  • The downstream of the Ganga is known as the Meghna.
  • The Meghna River flows into the Bay of Bengal and forms Sundarban Delta.

3) The Brahmaputra River System

The Brahmaputra River System is one of the largest river systems in Asia.
It originates in the Himalayas and flows through China, India, and Bangladesh.
It empties into the Bay of Bengal.
It is known by different names in different regions, like Yarlung Tsangpo in Tibet, Siang in Arunachal Pradesh, and Brahmaputra in Assam.
The river is fed by several major tributaries, such as the Dibang, Lohit, and Subansiri Rivers.

The Peninsular Rivers

The Peninsular Rivers such as the Mahanadi, the Godavari, the Krishna, and the Kaveri originate in the southern part of the country. These rivers flow towards the east and fall into the Bay of Bengal. While The Narmada River & The Tapti River flow towards the west, & drain into the Arabian Sea. These rivers provide water for irrigation, hydroelectric power generation, and other uses.

 Class 9 Geography Chapter 3 Notes

1) The Narmada Basin

  • The Narmada River originates from the Amarkantak Plateau in Madhya Pradesh.
  • It drains into the Arabian Sea in Gujarat.
  • It flows through the parts of Madhya Pradesh, Gujarat, and Maharashtra.
  • it is the fifth-largest river in India.
  • It is known for its landscapes, gorges, and waterfalls, such as the famous Dhuandhar Falls in Jabalpur, Madhya Pradesh.

2) The Tapi Basin

  • The Tapi River originates from the Satpura Range in Madhya Pradesh.
  • It flows through the Tapi Valley before falling into the Arabian Sea in Gujarat.
  • It flows through the parts of Gujarat, Maharashtra, and Madhya Pradesh.
  • it is the second-longest river in Gujarat.
  • It is known for its scenic beauty and is a major tourist attraction, especially during the monsoon season.

3) The Godavari Basin

  • The Godavari River originates from the Brahmagiri Hills in Maharashtra.
  • It flows through the Godavari Valley before falling into the Bay of Bengal.
  • It passes through parts of Maharashtra, Telangana, Andhra Pradesh, Chhattisgarh, and Odisha.
  • It is the second-longest river in India while the largest Peninsular river.
  • It is known for its landscapes, waterfalls, and the famous Godavari Pushkaram festival, which is celebrated every 12 years.
  • The Godavari River is also known as the Dakshin Ganga.

4) The Mahanadi Basin

  • The Mahanadi River rises from the foothills of the Dandakaranya Range in Chhattisgarh.
  • It falls into the Bay of Bengal.
  • It covers an area of about 141,600 square kilometers.
  • It passes through parts of Chhattisgarh, Odisha, Jharkhand, and Maharashtra.
  • It is known for its scenic beauty, waterfalls, and the Hirakud Dam, which is one of the longest dams in the world.

5) The Krishna Basin

  • The Krishna River originates from a spring near Mahabaleshwar in Maharashtra.
  • It falls into the Bay of Bengal.
  • It flows through the parts of Maharashtra, Karnataka, Telangana, and Andhra Pradesh.
  • It is known for its scenic beauty, waterfalls, and the famous Srisailam Dam, which is one of the largest hydroelectric projects in India.

6) The Kaveri Basin

  • The Kaveri River originates from the Brahmagiri Hills in Karnataka.
  • It falls into the Bay of Bengal.
  • It covers an area of about 81,155 square kilometers.
  • It flows through the parts of Karnataka, Tamil Nadu, and Kerala.
  • It is prone to disputes between the states of Karnataka and Tamil Nadu over sharing of its waters.

The peninsular rivers support a wide variety of flora and fauna and provide a habitat for several species of fish and other aquatic creatures. Some small peninsular rivers that flow towards the east are:

  • The Damodar
  • The Brahmani
  • The Baitarni
  • The Subarnrekha


  • India is home to many lakes, both natural and man-made. These lakes provide a source of freshwater & support rich biodiversity.
  • The natural lakes in India are formed due to the action of glaciers, tectonic activity, erosion, and weathering such as the Dal Lake in Jammu and Kashmir, Chilika Lake in Odisha, and the Vembanad Lake in Kerala.
  • The Wular Lake in Jammu and Kashmir is the largest freshwater lake in India.
  • The man-made lakes in India are the Hussain Sagar Lake in Telangana, the Sukhna Lake in Chandigarh, and the Powai Lake in Mumbai.
  • Most lakes are permanent while some are seasonal such as the Sambhar Lake in Rajasthan.
  • Many lakes in India are also important for economic activities such as fishing, boating, and tourism

Importance of Lakes

  • Lakes in India play an important role in the environment, economy, and culture of the country.
  • Lakes provide essential habitats for fish, birds, and other aquatic animals.
  • Many lakes in India are important sources of freshwater for irrigation, drinking, and industrial purposes.
  • Lakes attract millions of visitors every year for recreational activities such as boating, fishing, and bird watching.
  • They regulate the climate of the surrounding regions.
  • Lakes help regulate the flow of rivers and prevent flooding during heavy rains.

Role of Rivers in the Economy

  • Rivers play a significant role in the economy of a country in many ways-
  • Rivers are a primary source of fresh water for drinking, irrigation, and industrial purposes.
  • Rivers are used for the transportation of goods and people.
  • Rivers provide a significant source of renewable energy through hydroelectric power generation.
  • Rivers provide a range of activities such as rafting, kayaking, fishing, and other recreational activities.
  • Rivers provide essential habitats for aquatic plants and animals.

River Pollution

The main sources of river pollution are human activities such as improper waste disposal, industrial effluent discharge, and agricultural runoff. These activities release a range of pollutants such as organic matter, nutrients, heavy metals, pesticides, and other toxic substances into the river.
It impacts on the environment, economy, and human health. It affects the quality of water for drinking, irrigation, and industrial purposes.
The government has implemented various measures to prevent and control river pollution such as the installation of sewage treatment plants, the enforcement of pollution control regulations, and the promotion of sustainable agricultural practices.


The Class 9 Geography Chapter 3 Notes provide students with a comprehensive understanding of the river systems & their importance in India. By studying and practicing these NCERT notes, students can enhance their knowledge, improve their problem-solving skills, and perform better in their exams. You can access them by visiting the website. If you have any other queries about Drainage Class 9 Geography Chapter 3 Notes feel free to reach us so that we can revert back to us at the earliest possible.


1. What are drainage notes?

Drainage notes are brief written observations and measurements related to drainage systems, such as the location of drains, their size, and the direction of flow.

2. What are the types of drainage?

There are two main types of drainage:
Surface drainage- the removal of excess water from the surface of the ground.
Subsurface drainage- the removal of water from beneath the ground surface.

3. Why is drainage important?

Drainage is important because it helps to prevent water accumulation and associated problems such as flooding, erosion, and waterlogging.

4. What is Water Divide Class 9?

An imaginary line that separates one drainage basin from another. It is the line along high elevations, such as a mountain range, where water flows downhill on one side to one river, and on the other side to another river.

5. What is Gorge class 9?

A gorge is a narrow, steep-sided valley that is formed by the action of a river or a glacier.

Rate this post

Leave a Comment