Difference between Drainage Pattern and Drainage system
Drainage or river Patterns:
Depending on the slope of land, underlying rock structure and climate of an area, the
streams in a drainage basin form certain patters. Different types of drainage pattern are
as follows:
a. Dendritic Drainage Pattern: When the river channel follows the slope of the
terrain, it develops dendritic pattern. The stream and its tributaries resemble the
branches
of
a
tree.
Hence,
it
is
called
dendritic
pattern.
b. Trellis Drainage Pattern: When a river is joined by its tributaries at almost right
angles, it develops a trellis pattern. Trellis pattern develops where hard and soft
rocks
exist
parallel
to
each
other.
c. Rectangular
rectangular
Drainage
Pattern: When rocks
pattern
are
strongly
joined, then
develops.
d. Radial Drainage Pattern: When the streams flow in different directions from a
central peak or dome like structure, a radial pattern is developed.
It is important to note that a combination of different patterns may develop in the same
drainage basin.
The drainage or river systems ;
There are three river system found in india,they are
1. The Indus River System
2. The Ganga River System
3. The Brahmaputra River System
Now these river system has been categorised under two broad river system
a. The Himalayan Rivers system:- includes
1. The Indus River System
2. The Ganga River System
b. The Peninsular Rivers system : include
1. The Brahmaputra River System
The Himalayan Rivers: Most of the Himalayan Rivers are perennial, i.e. they have
water throughout the year.(tell me why ?)
River System: A river along with its tributaries forms a river system.
The Indus River System:
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The river Indus originates in Tibet; near Lake Mansarowar. It enters India in the
Ladakh district of Jammu & Kashmir.
Zaskar, Nubra, Shyok and Hunza are the main tributaries which join the Indus in
Kashmir region.
After flowing through Baltistan and Gilgit, the Indus emerges from the
mountains(mean plain region me utarta hai) at Attock.
Sutlej, Beas, Ravi, Chenab and Jhelum join together and enter the Indus near
Mithankot in Pakistan. After that, the Indus flows southwards and finally reaches
the Arabian Sea, east of Karachi.
Indus is 2900 km long. The Indus plain has a very gentle slope. A little over onethird of the Indus basin is located in India; in the states of Jammu & Kashmir,
Himachal Pradesh and Punjab. The rest of the portion is in Pakistan.
The Ganga River System
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The headwaters of Ganga are called Bhagirathi. It is fed by the Gnagotri Glacier.
It is joined by Alaknanda at Devprayag in Uttarakhand.
Ganga emerges from the mountains on to the plains at Haridwar.
Yamuna, Ghaghra, Gandak and Kosi are the major tributaries of Ganga. Yamuna
originates from the Yamunotri Glacier in the Himalayas. It meets Ganga at
Allahabad.
Gaghra, Gandak and Kosi rise in the Nepal Himalaya.
Chambal, Betwa and Son are the major tributaries which come from the
peninsular uplands.
After taking waters from various tributaries, Ganga flows towards east till Farakka
(West Bengal). The river bifurcates at Farakka. The Bhagirathi-Hooghly (a
distributary) flows towards south to the Bay of Bengal.
The mainstream flows southwards into Bangladesh; where it is joined by the
Brahmaputra. It is known as Meghan; further downstream.
Finally, the Ganga and the Brahmaputra flow into the Bay of Bengal forming the
Sunderban Delta. The total length of Ganga is 2500 km.
The Brahmaputra River System:

The Brahmaputra rises in Tibet; east of Mansarowar lake. It is a little longer than
the Indus. Most of the course of the Brahmaputra lies outside India. It flows
eastwards parallel to the Himalayas.
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After reaching Namcha Barwa, it enters India in Arunachal Pradesh through a
gorge. It is known as Dihang in this region. It is joined by Dibang, Lohit, Kenula
and many other tribuatries and finally forms the Brahmaputra in Assam.
Unlike other north Indian rivers the Brahmaputra gets huge deposits of silt on its
bed. This results in rising of the river bed. It also shifts its channel frequently.
The Peninsular Rivers: Most of the Peninsular Rivers are seasonal because they
depend on rainfall for water. These rivers have shorter and shallower courses;
compared to the Himalayan rivers. Most of the major rivers of the Peninsula flow
eastwards and drain into the Bay of Bengal. These rivers make deltas at their mouths.
The Narmada and Tapi are the only long rivers, which flow westwards and make
estuaries. The drainage basins of the peninsular rivers are smaller in size.
The Narmada Basin: The Narmada rises in the Amarkantak hills in the Madhya
Pradesh. The Narmada basin covers parts of Madhya Pradesh and Gujarat. All the
tributaries of the Narmada are very short. Most of the tributaries join the Narmada at
right angles.
The Tapi Basin: The Tapi rises in the Satpura ranges, in Betul district of Madhya
Pradesh. The basin of Tapi covers parts of Madhya Pradesh, Gujarat and Maharashtra.
The Godavari Basin: This is the longest Peninsular river. Its drainage basin is also the
largest among the peninsular river basins. The Godavari is about 1500 km long. It
originates from the slopes of the Western Ghats in Nasik district of Maharashtra and
drains into the Bay of Bengal. The Godavari basin covers parts of Maharashtra, Madhya
Pradesh, Orissa and Andhra Pradesh. Purna, Wardha, Pranhita, Manjra, Waiganga and
Penganga are the main tributaries of Godavari.
The Mahanadi Basin: This river originates in the highlands of Chhattisgarh and drains
into the Bay of Bengal. It is about 860 km long. The Mahanadi basin covers
Maharashtra, Chhattisgarh, Jharkhand and Orissa.
The Krishna Basin: The Krishna originates near Mahabaleshwar and drains into the
Bay of Bengal. It is about 1400 km long. Tungbhadra, Koyana, Ghatprabha, Musi and
Bhima are some of its tributaries. The Krishna basin covers Maharashtra, Karnataka
and Andhra Pradesh.
The Kaveri Basin: The Kaveri originates in the Brahmagiri range of the Western Ghats
and drains into the Bay of Bengal. It is about 760 km long. Amravati, Bhavani, Hemavati
and Kabini are its main tributaries. The Kavery basin covers Karnataka, Kerala and
Tamil Nadu.
LAKES
A large water body which is surrounded by land is called a lake. Most of the lakes are
permanent, while some contain water only during the rainy season. Lakes are formed
by the action of glaciers and ice sheets, by wind, river action and by human activities.
Ox-bow Lake: A lake formed when a meandering river is cut off from the mainstream.
The shape of this lake resembles an ox-bow.
Lagoon: When the lake is formed by spits and bars in coastal areas, it is called a
lagoon. Chilika lake, Pulicat lake, Kolleru lake, etc. are examples of lagoon.
Glacial Lake: A lake formed by melting of glacier is called a glacial lake. Most of the
lakes in the Himalayan region are glacial lakes.
Wular lake (Jammu & Kashmir) is the largest freshwater lake in India. It was formed by
tectonic activity.
Benefits of a Lake: A lake helps in preventing flood by regulating the flow of river.
During dry seasons, a lake helps to maintain an even flow of the river. Lakes can also
be used for generating hydel power.
Role of rivers in the economy: Rivers have been the centre of human civilization since
ancient times. Even today, many big cities are situated on the bank of a river. River
water is used for irrigation, navigation, hydroelectricity, fisheries, etc.
River Pollution: 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 being drained out of the rivers reducing their volume. On the other hand, 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.
NCERT Solution
Question – 1 - Which one of the following describes the drainage patterns resembling
the branches of a tree?
a.
b.
c.
d.
Radial
Centrifugal
Dendritic
Trellis
Answer: (c) Dendritic
Question – 2 - In which of the following states is the Wular lake located?
a.
b.
c.
d.
Rajasthan
Punjab
Uttar Pradesh
Jammu and Kashmir
Answer: (d) Jammu and Kashmir
Question – 3 - The river Narmada has its source at
a.
b.
c.
d.
Satpura
Amarkantak
Brahmagiri
Slopes of the Western Ghats
Answer: (b) Amarkantak
Question – 4 - Which one of the following lakes is a salt water lake?
a.
b.
c.
d.
Sambhar
Wular
Dal
Gobind Sagar
Answer: (a) Sambhar
Question – 5 - Which one of the following is the longest river of the Peninsular India?
a.
b.
c.
d.
Narmada
Godavari
Krishna
Mahanadi
Answer: (b) Godavari
Question – 6 - Which one amongst the following rivers flows through a rift valley?
a.
b.
c.
d.
Mahanadi
Krishna
Tungabhadra
Tapi
Answer: (d) Tapi
Question – 7 - What is meant by a water divide? Give an example.
Answer: Any elevated area separates two drainage basins. Such upland is called a
water divide.
Question – 8 - Which is the largest river basin in India?
Answer: The Ganga River Basin
Question – 9 - Where do the rivers Indus and Ganga have their origin?
Answer: In the Himalayas
Question – 10 - Name the two headstreams of the Ganga. Where do they meet to form
the Ganga?
Answer: Bhagirathi and Alaknanda are the two headstreams of Ganga. They meet at
Devprayag to form the Ganga.
Question – 11 - Why does the Brahmaputra in its Tibetan part have less silt, despite a
longer course?
Answer: Since Tibet is a cold and dry area, so Brahmaputra in this part carries less silt
despite having a longer course.
Question – 12 - Which two Peninsular rivers flow through trough?
Answer: Narmada and Tapi
Question – 13 - State some economic benefits of rivers and lakes.
Answer: Lake can be used for generating hydroelectricity. A lake can be a good tourist
attraction. Rivers have been the centre of human civilization since ancient times. Even
today, many big cities are situated on the bank of a river. River water is used for
irrigation, navigation, hydroelectricity, fisheries, etc.
Question – 14 - Below are given names of a few lakes of India. Group them under two
categories – natural and created by human beings.
(a)Wular (b) Dal (c) Nainital (d) Bhimtal (e) Gobind Sagar (f) Loktak (g) Barapani (h)
Chilika (i) Sambhar (j) Rana Pratap Sagar (k) Nizam Sagar (l) Pulicat (m) Nagarjuna
Sagar (n) Hirakund
Answer: Natural Lakes: Wular, Dal, Bhimtal, Loktak, Barapani, Chilika, Sambhar, Pulicat
Man-made Lakes: Gobind Sagar, Rana Pratap Sagar, Nizam Sagar, Nagarjuna Sagar,
Hirakund
Question – 15 - Discuss the significant difference between the Himalayan and the
Peninsular rivers.
Answer:
Question – 16 - Compare the east flowing and the west flowing rivers of the Peninsular
plateau.
Answer: The east flowing rivers of the Peninsular part drain into Bay of Bengal and form
deltas at their mouths. The west flowing rivers drain into the Arabian Sea and form
estuaries. Most of the east flowing rivers are longer, compared to most of the west
flowing rivers.
Question – 17 - Why are rivers important for the country’s economy?
Answer: Rivers are the major source of water for irrigation and hence are important for a
country where farming is still the occupation of the largest portion of population. Many
major rivers serve as important channels for transporting goods and people and thus
play important role in the supply chain. Many multipurpose projects have been built on
most of the major rivers in India. Rivers are important source of fish to a large
population.