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Class 9
Social Science
Geography |Drainage
Crafted with love
By Digraj Singh Rajput
 Geography |Drainage
Drainage

Drainage system of India

Himalayan rivers Peninsular rivers

Indus Ganga Brahmaputra

Mahanad
Narmada Tapi Godavari Krishna Kaveri
i

Lakes → Role of rivers in economy → River Pollution

 Geography |Drainage
Drainage Describes the river system of an area

Drainage Basin Area drained by a single river system

Water Divide An elevated area, such as mountains or an

upland, separates two drainage basins.

Drainage system of India

Himalayan Rivers Peninsular Rivers

● Mountain and glaciers ● Central highland, Western ghats &

● Perennial Eastern ghats.
● Long courses ● Seasonal
● Meanders, oxbow lakes, Deltas ● Shorter and shallower courses
● Young and youth full ● Estuaries,well-adjusted valleys.
● Relatively old
 Geography |Drainage
Himalayan Rivers System
● Originating in Tibet(near Mansarovar lake).
The Indus River ● Flowing west, enters India in ladakh
System ● Joining several tributaries before reaching the Arabian Sea.
● It covers 2900 km and has a gentle slope, with a third of its
basin in India and the rest in Pakistan.

Left bank Zaskar, Jhelum, Chenab, Ravi, Beas, Sutlej

Indus
Right bank Shyok, Nubra
● The Bhagirathi originating(Gangotri Glacier), joined Alaknanda at
Devaprayag and form Ganga
The Ganga ● Join by tributaries (Yamuna, Ghaghara, Gandak, Kosi, Chambal, Betwa,
River System and Son).
● It flows east, splitting at Farakka in West Bengal into Bhagirathi-Hooghly
● The Ganga merges with Brahmaputra in Bangladesh, forming Meghna,
and flows into the Bay of Bengal.
● The Ganga is over 2500 km long with a gentle slope, creating large
meanders and delta(Sundarban).

Left bank Ghaghara, Gandak, Kosi

Ganga
Right bank Yamuna (Chambal, Sindh, Betwa, Ken), Son
 Geography |Drainage
● The Brahmaputra starts in Tibet(Mansarovar lake) and enters India in AP.
The Brahmaputra ● It joins rivers like Dibang and Lohit in Assam.
River System ● It carries more water and silt in India, with many islands.
● It forms the world's largest riverine island
● The river causes floods and shifts its channel often.

● The Western Ghats form the main water divide in Peninsular India.
● Major rivers like Mahanadi, Godavari, Krishna, and Kaveri flow east to the Bay of
Peninsular Rivers Bengal, forming deltas.
● Narmada and Tapi are the only long rivers flowing west, creating estuaries.
● Peninsular river basins are smaller in size.
Major Peninsular Rivers

Origin,Amarkantak (MP), Flow in Rift valley, Form deep gorge, Dhuadhar falls, [MP,MH,Gujarat]
Narmada
Tributaries → Kolar, Tawa, Banjar

Origin,Satpura ranges Betul (MP), [MP, MH, Gujarat]

Tapi
Tributaries → Sipra, Kapra, Mona
 Geography |Drainage

The Dibang and Lohit are the tributaries of river

A. Ganga

B. Indus

C. Brahmaputra

D. Narmada
 Geography |Drainage

Nasik Western Ghats(MH), Largest peninsular river

Godavari (Dakshin Ganga), [MH, CH, Orissa, AP, Telangana]
Tributaries → Purna,Wardha,Pranhita,Manjra,Wainganga,
Penganga

Sihawa Highlands of Chhattisgarh, [MH, CH, JK, Odisha]

Mahanadi
Tributaries → Jonk, Tel.

Mahabaleshwar in sahyadri(WG), [MH, Karnataka, Telangana]

Krishna
Tributaries → Tungabhadra, Koyana, Ghatprabha,Musi,Bhima

Brahmagiri hills(Western Ghats), [Karnataka, Kerala, T.N]

Kaveri
Tributaries → Amravati, Bhavani, Hemavati and Kabini
 Geography |Drainage
Lakes

Natural Artificial or Man Made

● Guru gobind sagar lake
Salt water ● Indira sagar lake
Ox-Bow Lakes/lagoons Freshwater lakes
lake
● Chilika lake ● Dal Lake ● Sambhar lake
● Pulicat lake ● Loktak lakes
● Kolleru lake ● Nainital
● Bhimtal

Role of rivers in economy → River Pollution

● Irrigation ● Increased demand for water reduces river volume and
● Navigation (Transport) quality.
● Hydro- power generation (electricity) ● Untreated sewage and industrial waste pollute rivers.
● Industry ● Pollution harms the river’s self-cleaning ability.
● Rising pollution has prompted action plans for river cleaning.

The National River Conservation Plan (NRCP), started in 1995, aims to improve water quality in major Indian
rivers by reducing pollution. It expanded from the Ganga Action Plan (GAP) of 1985.
 Geography |Drainage

Name the salt water lake of Rajasthan.

A. Chilika

B. Pulicat

C. Sambhar

D. Loktak lakes
 Geography |Drainage
Key Words

Drainage Basin: A drainage basin is the land where Peninsular Rivers: In India, the main water divide for
rainwater collects and flows into a river, lake, or sea. It is peninsular rivers is the Western Ghats, a mountain range
also called a catchment area, river basin, or water basin. that runs from north to south along the western side of
India. Rivers from here flow into the Bay of Bengal.
Water Divide: A water divide is the high land (like a
mountain ridge) that separates two areas where water Himalayan Rivers: The Himalayan rivers, like the Indus
flows into different rivers or lakes. River, flow into a big area called the Indus Basin. The
Indus gets water from other rivers like the Jhelum,
Chenab, Ravi, Beas, and Sutlej. Most other rivers from
River System: A river system is a big group of rivers, the Himalayas flow into the Ganges-Brahmaputra Basin.
streams, and lakes that are all connected. The water from
smaller rivers (called tributaries) joins bigger rivers. Basin: A basin is an area of land where all the water from
rivers and streams drains into one place. It’s like a big bowl
that collects water.
Tributaries: Tributaries are smaller rivers or streams that
flow into a bigger river or lake. Meander: A meander is a bend or curve in a river. It’s like
when a river twists and turns as it flows.
 Geography |Drainage
Key Words

Oxbow: An oxbow lake is a U-shaped lake that forms Lake : A lake is a large, typically freshwater body of water
when a river makes a sharp curve, and later the river cuts surrounded by land. It forms naturally or artificially and is
through that curve, leaving the old part of the river as a often fed by rivers, streams, or precipitation.
separate lake.
Hydro-power Generation: Hydro-power generation is
Semi-arid Regions: Semi-arid regions are places that are generating electricity using water. This is done by using the
partly dry. They get less than 20 inches of rain every year, power of water that falls or flows, like in rivers or
so the land is not very wet. waterfalls.
Urbanisation: Urbanisation is the process by which an
Splits: To "split" means to break something into two or increasing percentage of a population lives in urban areas,
more pieces, like tearing a piece of paper into halves. leading to the growth and expansion of cities. It typically
involves changes in lifestyle, infrastructure, and land use.

Lagoon: A lagoon is a small, shallow area of water that is Industrialisation: is the process of developing industries on
separated from a bigger body of water, like an ocean, by a large scale, shifting an economy from agrarian-based to
islands or coral reefs. manufacturing-based. It involves technological innovation,
mass production, and the growth of factories and
infrastructure.
 Geography |Drainage

Explain differences between Himalayan Rivers and Peninsular Rivers.

Himalayan Rivers Peninsular Rivers

● These rivers originate from the lofty ranges of the ● These rivers originates in the peninsular plateau.
Himalayas.
● They consist of small basin and catchment area.
● They have large basin and catchment area.
● They mainly flow in shallow valleys.
● They form deep l-shape valleys known as Gorge.
● These rivers mostly flow in the rainy season as they
● These rivers are known as Perennial and water flows are rain-fed.
throughout the year.
● They do not form meanders and flow more or less
● These rivers form meanders and often shift their ul se straight course.
courses.
● They form smaller deltas and estuaries.
● They also form bIa deltas at their mouth.
 Geography |Drainage

Write main features of Indus Basin River System.

● The river Indus rises in Tibet, near lake Mansarovar.

● Flowing west, it enters India in the Ladakh district of Jammu & Kashmir. It forms a picturesque gorge
in this part.
● It flows through Baltistan and Gilgit and emerges from the mountain at Attock.
● All its major tributaries-the Satluj, the Beas, the Ravi, the Chenab and the Jhelum-join together to
enter the Indus near Mithankot in Pakistan.
● Beyond this, the Indus flows southwards eventually reaching the Arabian Sea, east of Karachi. Indus
is 2,900-km long and is one of the longest rivers of the world.
 Geography |Drainage

Give main characteristics of the Ganga River System.

● The headwaters of the Ganga called the 'Bhagirathi' is fed by the Gangotri Glacier and joined by
Alaknanda at Devaprayag in Uttarakhand.
● At Haridwar, the Ganga emerges from the mountains on to the plains.
● Its tributaries are flooding parts of the northern plains every year, causing widespread damage to
life and property but enriching the soil for the extensive agricultural lands.
● Enlarged with the waters from its right and left bank tributaries, the Ganga flows eastward till
Farakka in West Bengal. This is the northern most point of Ganga Delta.
● The mainstream flows southwards into Bangladesh and is joined by the Brahmaputra. This mighty
river along with Brahmaputra flows into the Bay of Bengal and the delta formed by these rivers is
known as Sundarban delta.
 Geography |Drainage

What are the main characteristics of the mighty river Brahmaputra?

● The Brahmaputra starts in Tibet, near Mansarovar Lake, close to the Indus and Satluj rivers.

● It is a little longer than the Indus and flows mostly outside India.

● In Tibet, the river carries less water and silt because the area is cold and dry.

● In India, the river flows through areas with heavy rain, so it carries a lot of water and silt.

● In Assam, the river has a wide, shifting path and creates many islands.
 Geography |Drainage

Explain differences between east flowing peninsular rivers and west flowing peninsular
rivers.

The West flowing rivers: The East flowing rivers:

● These rivers originate in Central India and ● These rivers originate from the Western Ghats and
flow westwards. flow eastwards.
● They form estuaries since they flow from ● They all form deltas at their mouths.
rift valleys.
● They drain into the Bay of Bengal.
● They drain into the Arabian Sea.
● They have large volume of water.
● They have lesser volume of water.
● Examples: Mahanadi, Godavari, Krishna and Kaveri
● Examples: Narmada and Tapi
 Geography |Drainage

What types of lakes are found in India? Give suitable examples.

India has many lakes, which vary in size and type. Some are always full of water, while others only have
water during the rainy season. Some lakes are made by glaciers, and others are created by humans.

● Saltwater Lakes: These are found in coastal areas, like Chilika, Pulicat, and Kolleru. Some, like
Sambhar Lake in Rajasthan, are made where water drains into the land and are used to produce
salt.
● Freshwater Lakes: Most of these are in the Himalayan region and are formed by glaciers. When
glaciers melted, they left behind water in basins. The Wular Lake is the largest freshwater lake in
India. Other examples include Dal, Bhimtal, Nainital, Loktak, and Barapani.
● Man-made Lakes: Some lakes are created by building dams on rivers to make electricity, control
floods, or store water. Examples are Guru Gobind Sagar (Bhakra Nangal Project), Nizam Sagar,
Nagarjuna Sagar, and Rana Pratap Sagar.
 Geography |Drainage

Why are rivers important for the country's economy?

The rivers are important for the country's economy due to the following reasons -

● It is an important source of natural freshwater, which is required for the survival of most of the
animals including human.
● River water is used for various purposes like domestic, industrial, agriculture.
● The presence of rivers boosts trade and commerce by helping in the easy transport of goods. They
are also a potential source of energy.
● River water is also used in running the hydro-electric dams.
● It is also used for navigation and transport, thus, important for commercial activities.
● It also provides fishing and great scenic and recreational value. Thus, serve as good tourist spots.
 Geography |Drainage

What are the main causes of the pollution in the rivers of India? How can we
prevent this kind of pollution?

The main causes of pollution of Indian rivers are:

● The growing domestic, municipal, industrial and agricultural demand for water from rivers naturally affects
the quality of water.
● As a result, more and more water is drained out of the rivers, thereby reducing their volume.
● A heavy load of untreated sewage and industrial effluents are emptied into the rivers.
● This affects not only the quality of water but also the self-cleansing capacity of the river.
● The increasing urbanisation and industrialisation has increased the pollution levels of the rivers.

How to prevent pollution:

● Factory waste should be cleaned before going into rivers.

● People living near rivers should know how dirty rivers are and how hard it is to clean them.
● During festivals, people put idols and other things in the river, which causes pollution. This needs to stop.
 Geography |Drainage

Give characteristics of the Ganga-Brahmaputra river system.

Give main characteristics of the largest peninsular river.

Why do Himalayan rivers get flooded every year? What are its advantage?

'Lakes are of great value to human beings'. Justify the statement with three suitable reasons.

How do urbanisation and industrialisation cause river pollution? Suggest three measures to
control river pollution.

State some economic benefits of rivers and lakes.