Most ancient civilizations
grew along the banks of rivers. Even today, millions of people all
over the world live on the banks of rivers and depend on them for
All of us have seen a river - large or small, either flowing through
our town, or somewhere else. Rivers are nothing more than surface
water flowing down from a higher altitude to a lower altitude due
to the pull of gravity. One river might have its source in a glacier,
another in a spring or a lake. Rivers carry dissolved minerals, organic
compounds, small grains of sand, gravel, and other material as they
flow downstream. Rivers begin as small streams, which grow wider as
smaller streams and rivers join them along their course across theland.
Eventually they flow into seas or oceans. Most rivers With the exception
of the Nile, flow towards the Equator. The flow in most rivers is
not uniform, which means that sometimes there are floods and sometimes
no water flows in them. Flood control projects attempt to reduce the
variation in flow.
Unfortunately most of
the world's major rivers are heavily polluted, but two of the world's
largest river systems-the Amazon, that drains a vast area of South
America and the Congo in sub-Saharan Africa- remain relatively healthy.
This is because both have few industries and a small human population
in their watersheds.
Some facts about rivers
The Nile, 6695 km long,
and the Amazon 6437 km long, are the world's two longest rivers. Sometimes,
measurements of their lengths can vary according to the criteria used
An Arab philosopher and
physician Avicenna suggested, nearly 1000 years ago, that landscapes
changed largely as a result of the action of running water. His views
were largely ignored until the 16th century.
The longest river in Asia
is the Yangtze, which is 5472 km long.
The world's highest waterfall
are the Angel Falls in Venezuela, 979 m high, over 780 m of which
is an uninterrupted drop.
Rivers in India
India has a large number of rivers that are lifelines for the millions
living along their banks. These rivers can be categorized into four
Rivers that flow down from
the Himalayas and are supplied by melting snow and glaciers. This
is why these are perennial, that is, they never dry up during the
The Deccan Plateau rivers,
which depend on rainfall for their water
The coastal rivers, especially
those on the west coast, which are short and do not retain water throughout
The rivers in the inland
drainage basin of west Rajasthan, which depend on the rains. These
rivers normally drain towards silt lakes or flow into the sand.
The major rivers in
India are described here:
This is considered the holiest of all the great rivers of India. It
has its source at the Gangotri glacier, where it flows from the cave
Goumukh, as the Bhagirathi, which then joins the River Alaknanda as
it flows towards Devaprayag. The largest tributary of the river is
the Ghaghara, which flows from the northern Nepal region and joins
it before Patna in Bihar. Another major tributary is the Yamuna originating
in the Yamunotri glacier, and flows through Delhi and Agra. Others
are the Gomti, Gandak, Son, Kosi, Chambal, Sarda, etc. The Ganga is
the lifeline for more than 500 million people living along its banks.
The water of the river Ganges is considered so sacred that people
keep it in their homes for use in prayers on important occasions such
as at the time of death.
Most cities along the
river do not have sewage treatment plants and those that do have them
can handle only part of the waste water. Millions of tonnes of untreated
sewage are dumped daily into the river from the cities that lie along
its banks. Bathing and washing also contribute to the pollution as
most of the soap that is used is made from chemical substances. The
river is also polluted by human and animal faeces. Industrial units
that lie along the banks of the river discharge all the waste into
the river and only a few of them have proper treatment facilities.
Rising from the Yamunotri glacier in the Tehri Garhwal District in
the Himalayas, the Yamuna flows for about 1380 km almost parallel
to the Ganga till they meet at Allahabad. It flows through a number
of important towns, Delhi, Mathura, Brindaban, and Agra to name some.
Since ancient times, the Doab region, where the Ganga and the Yamuna
flow, has been considered one of the most fertile areas in the subcontinent.
Today however, this majestic river is polluted with domestic waste,
silt, and industrial waste. The 22-km stretch between Wazirabad and
the Okhla barrage in Delhi is only 2% of the catchment area, but it
contributes about 80% of the river's total pollution load. The Hindon
Canal also discharges waste from Uttar Pradesh in this stretch. Among
the many casualties are birds and fish. There was a time when bird
watchers had identified as many as 30 species of birds near the Yamuna,
many of them exotic, such as the red-crested pochard and the godwit.
This mighty river rises in western Tibet in the Manasarovar region.
It flows eastwards through the Himalayas, curves back across Arunachal
Pradesh and Assam, then turns south to join the Padma and Ganga in
Bangladesh and finally enters the Bay of Bengal. It is known by different
names in different regions: as it flows through Tibet it is known
as the Tsangpo., In the north-eastern states of Arunachal Pradesh
and Assam, it is known as the Siang or Dihang. It is longer and more
voluminous than the Ganga, and gushes down with enormous force for
most of its course through the mountain regions and the forests of
north-east India. A unique feature of this river is that it is navigable
even at a height of 10 000 feet.
When compared to the
other major rivers in India, the Brahmaputra is less polluted but
it has its own problems: petroleum refining units contribute most
of the industrial pollution load into the basin along with other medium
and small industries. The main problem facing the river basin is that
of constant flooding. Floods have been occurring more often in recent
years with deforestation, and other human activities being the major
Known as the Sindhu in ancient times, the Indus was the cradle of
India's great Indus Valley civilization. It has its source near Manasarovar
close to southwestern Tibet, at an altitude of 16,000 feet and flows
westward, through the Himalayas into Ladakh, and then through Sind
and Punjab in Pakistan into the Arabian Sea.
After flowing eleven
miles beyond Leh, the Indus is joined by its first tributary, the
Zanskar. When it enters the plains, its famous five tributaries -
the Jhelum, Chenab, Ravi, Beas, and Sutlej - that give Punjab its
name (land of the five rivers) join it.
The name India is said
to have its roots in Sindhu (Indus), the great river that constitutes
the most imposing feature of that part of the subcontinent, home to
some of the earliest civilizations.The river Sindhu has been invoked
numerous times in the Vedic literature together with those of other
gods and goddesses.
This is the largest west-flowing river in India and originates from
the Mekhala range in Shahdol district, Madhya Pradesh. It flows 1300
km west through the states of Madhya Pradesh and Gujarat before draining
into the Gulf of Khambhat in the Arabian Sea. It is said to be one
of the most beautiful rivers in India. In terms of its catchment area
it is the seventh largest among the fourteen major river basins in
the country. It is stated in the Matsya Purana that the mere sight
of the river washes away all sins. With many short tributaries flowing
into it from north and south, the Narmada basin forms a very important
topographic feature of peninsular India.
About 20% of the population
along the river lives in the urban areas and the rest in the rural
areas: Jabalpur, Hoshangabad, and Khargone in Madhya Pradesh, and
Bharuch in Gujarat are some important cities located on the banks.
The major cause of pollution is run-off from agricultural activities
yet the pollution level is estimated to be lower than in other major
This river is considered the lifeline of Orissa, through which it
flows. It originates in south-eastern Madhya Pradesh near Raipur.
In the upper drainage basin of the Mahanadi, which is centred on the
Chhattisgarh Plain, periodic droughts contrast with the situation
in the delta region where floods may damage the crops in what is known
as the rice bowl of Orissa. The Hirakud Dam, constructed in the middle
reaches of the Mahanadi, has helped in alleviating these adverse effects
by creating a reservoir.
This river originates in the Sahyadri range to the northeast of Mumbai
in Maharashtra. It flows through that state and Andhra Pradesh before
entering the Bay of Bengal. Its drainage basin is one of the largest
in the country, second in size only to that of the Ganga; its delta
on the east coast is also one of the country's main rice-growing areas.
Despite the large catchment area the water available is only moderate
because of the medium levels of annual rainfall.
The Kaveri is worshipped as a jeeva-nadi or perennial river. It has
its origin in Talakaveri in the Kanara district of Karnataka and flows
sounthwards through Tamil Nadu and Karnataka.
The waters of the river have been a source of irrigation since antiquity;
in the early 1990s, an estimated 95 percent of the Kaveri was diverted
for agricultural use before it emptyied into the Bay of Bengal.