This document discusses water and dams. It begins by providing background on the chemical composition and states of water. It then discusses the importance of water for life and the environment. Several types of dams are described, including gravity dams, buttress dams, arch dams, and earth dams. The largest gravity dam, Bhakra Dam in India, is highlighted. Water pollution from various point and nonpoint sources is also mentioned. The document stresses that with population growth, humans are putting increasing pressure on limited water resources through activities that reduce water quality.

1. Water and Dams
Made By:- Nipun Sharma
Class:- X-A
Roll No.- 21

2. Water is a chemical substance with the chemical formula H2O.
A water molecule contains one oxygen and
two hydrogen atoms connected by covalent bonds. Water is
a liquid at ambient conditions, but it often co-exists
on Earth with its solid state, ice, and gaseous state (water
vapor or steam). Water also exists in a liquid crystal state
near hydrophilic surfaces. Under nomenclature used to
name chemical compounds, Dihydrogen monoxide is the
scientific name for water, though it is almost never used.

3. • Water is life ! It is a precondition for human, animal and
plant life as well as an indispensable resource for the
economy. Water also plays a fundamental role in the
climate regulation cycle.
• Protection of water resources, of fresh and salt water
ecosystems and of the water we drink and bathe in is
therefore one of the cornerstones of environmental
protection in Europe. The stakes are high and the issues
transcend national boundaries and concerted action at
the level of the EU is necessary to ensure an effective
protection.

4. • In its purest form, it's odorless, nearly
colorless and tasteless. It's in your body,
the food you eat and the beverages you
drink. You use it to clean yourself, your
clothes, your dishes, your car and
everything else around you. You can travel
on it or jump in it to cool off on hot
summer days. Many of the products that
you use every day contain it or were
manufactured using it. All forms of life need
it, and if they don't get enough of it, they
die. Political disputes have centered around
it. In some places, it's treasured and
incredibly difficult to get. In others, it's
incredibly easy to get and then squandered.

5. • Roughly 70 percent of an adult’s body is made up of
water.
• At birth, water accounts for approximately 80 percent
of an infant’s body weight.
• A healthy person can drink about three gallons (48
cups) of water per day.
• Drinking too much water too quickly can lead to water
intoxication. Water intoxication occurs when water
dilutes the sodium level in the bloodstream and
causes an imbalance of water in the brain.
• The earth is a closed system, similar to a terrarium,
meaning that it rarely loses or gains extra matter. The
same water that existed on the earth millions of years
ago is still present today

6. • The earth has a limited amount of
water. That water keeps going
around and around and around and
around and (well, you get the idea)
in what we call the "Water Cycle".
This cycle is made up of a few main
parts:
• evaporation (and transpiration)
• condensation
• precipitation
• Collection

7. Over two thirds of Earth's surface is covered
by water; less than a third is taken up by land. As
Earth's population continues to grow, people are
putting ever-increasing pressure on the planet's
water resources. In a sense, our oceans, rivers, and
other inland waters are being "squeezed" by human
activities—not so they take up less room, but so
their quality is reduced. Poorer water quality
means water pollution.

8. If there is something that seriously affects everyone
is, Water pollution. There are many causes of
water pollution. Water pollution come from two
different types of sources.
1) Pollutants being emitted directly into a water
body results in a “point source”, such as a pipe
from an industrial facility leaking toxics directly
into the water.
2) Pollutants being indirectly transported to the
water such as run off from fertilizers flowing in to
a larger body of water by rain results in a type of
pollution called “nonpoint source”.

9. Dams
• Dam is a solid barrier constructed at a suitable
location across a river valley to store flowing water.
• Storage of water is utilized for following objectives:
Hydropower
Irrigation
Water for domestic consumption
Drought and flood control
For navigational facilities
Other additional utilization is to develop fisheries

10. Structure of Dam
Gallery
Spillway
(inside dam)
Crest
NWL
Normal
water level
MWL
Max. level
Free board
Sluice way
Upstream
Down stream

11. • Abutment: Sides of the valley on which the structure of
the dam rests
• Galleries: small rooms like structure left within the dam for checking
operations.
• Diversion tunnel: Tunnels are constructed for diverting water before the
construction of dam. This helps in keeping the river bed dry.
• Spillways: It is the arrangement near the top to release the excess water
of the reservoir to downstream side
• Sluice way: An opening in the dam near the ground level, which is used
to clear the silt accumulation in the reservoir side.

12. • Gravity dams
• Buttress Dams
• Arch Dams
• Earth Dams
TYPES OF DAMS

13. • Gravity Dams:
• These dams are heavy
and massive wall-like
structures of concrete
in which the whole
weight acts vertically
downwards
Reservoir
Force
As the entire load is
transmitted on the small
area of foundation, such
dams are constructed
where rocks are competent
and stable.

14. • Bhakra Dam is the
highest Concrete
Gravity dam in Asia and
Second Highest in the
world.
• Bhakra Dam is across
river Sutlej in Himachal
Pradesh
• The construction of this
project was started in
the year 1948 and was
completed in 1963 .
• It is 740 ft. high above the deepest foundation as straight concrete dam being
more than three times the height of Qutab Minar.
• Length at top 518.16 m (1700 feet); Width at base 190.5 m (625 feet), and at
the top is 9.14 m (30 feet)
• Bhakra Dam is the highest Concrete Gravity dam in Asia and Second
Highest in the world.

15. Buttress Dam:
• Buttress Dam – Is a
gravity dam reinforced by
structural supports
• Buttress - a support that
transmits a force from a
roof or wall to another
supporting structure
This type of structure can be considered even if the foundation
rocks are little weaker

16.  These type of dams are
concrete or masonry dams
which are curved or convex
upstream in plan
 This shape helps to transmit
the major part of the water
load to the abutments
 Arch dams are built across
narrow, deep river gorges, but
now in recent years they have
been considered even for little
wider valleys.
Arch Dams:

17. Earth Dams:
• They are trapezoidal in
shape
• Earth dams are
constructed where the
foundation or the
underlying material or
rocks are weak to support
the masonry dam or
where the suitable
competent rocks are at
greater depth.
• Earthen dams are
relatively smaller in height
and broad at the base
• They are mainly built with
clay, sand and gravel,
hence they are also
known as Earth fill dam or
Rock fill dam