Hydro-power is power derived from the energy of
falling water and running water, which may be
harnessed for useful purposes.
▫ No pollution or waste produced.
▫ Renewable energy source.
▫ Very reliable energy source.
▫ Not expensive to maintain once the dam has been
▫ Building the dam is expensive and time taking.
▫ The dam will change the habitat and landscape
upstream, as much more land will be submersed.
▫ The land below the dam is also affected as the
flow of water is reduced.
Tidal energy, sometimes called tidal power, is the power
achieved by capturing the energy contained in moving water
in tides and open ocean currents . There are two types of
energy systems that can be used to extracted energy: kinetic
energy, the moving water of rivers, tides and open ocean
currents; and potential energy from the difference in height
between high and low tides. The first method - generating
energy from tidal currents - is becoming more and more
popular because people believe that it does not harm the
environment as much as barrages or dams Tidal power is
classified as a renewable energy source, because tides are
caused by the orbital mechanics of the solar system and are
considered inexhaustible. Tidal power has great potential for
future power and electricity generation because of the
essentially inexhaustible amount of energy contained in these
rotational systems. Tidal power is reliably predictable.
Due to geological changes molten rocks formed in the
deeper hot regions of earth’s crust are pushed upwards and
trapped in certain regions called hot spots . When
underground water comes in contact with the hot spots ,
steam is generated . Sometimes hot water from that
region finds outlet at the surface . Such outlets are known
as hot springs . The stream trapped in rocks is routed
through a pipe to turbine and is used to generate
electricity . The cost of production would not be much ,
but there are very few commercially viable sites where
such energy can be exploited.
HARDNESS OF WATER
The hardness of water is due to the presence of calcium
and magnesium minerals that are naturally present in the
water. The usual signs of a hard water supply are scaling
inside kettles, poor lathering of soaps and scum. It is
often referred to as soap eating water sample.
TYPES OF HARDNESS
Temporary hardness is a type of water hardness caused by
the presence of dissolved bicarbonate minerals When
dissolved these minerals yield calcium and magnesium cations
(Ca2+, Mg2+) and carbonate and bicarbonate anions(CO32-,
HCO3-). The presence of the metal cations makes the water
hard. However, unlike the permanent hardness caused by
sulfate and chloride compounds, this "temporary" hardness
can be reduced either by boiling the water, or by the addition
B. PERMANENT HARDNESS:
Permanent hardness is hardness (mineral content)that
be removed by boiling. When this is the case, it is
usually caused by the presence of calcium sulfate and/or
magnesium sulfates in the water, which do not precipitate out
as the temperature increases. Ions causing permanent hardness
of water can be removed using a water softener, or ion
Total Permanent Hardness = Calcium Hardness + Magnesium
EFFECTS OF HARD WATER
With hard water, soap solutions form a white precipitate (soap
scum) instead of producing lather, because the 2+ ions destroy the
surfactant properties of the soap by forming a solid precipitate
(the soap scum). A major component of such scum is calcium
stearate, which arises from sodium stearate, the main component
2 C17H35COO- + Ca2+ → (C17H35COO)2Ca
Hardness is defined as the soap-consuming capacity of a water
sample, or the capacity of precipitation of soap as a characteristic
property of water that prevents the lathering of soap.
# Hard water also forms deposits that clog plumbing.
# In boilers, the deposits from the hard water impair the flow of
heat into water, reducing the heating efficiency and allowing the
metal boiler components to overheat. Which can lead to the failure
of the boiler.
# In swimming pools, hard water is manifested by a cloudy
appearance to the water
Treatment of wastewater is actually a
remarkably simple process that utilizes
very basic physical, biological, and
chemical principles to remove
contaminants from water. Use of
mechanical or physical systems to treat
wastewater is generally referred to as
primary treatment, and use of
biological processes to provide further
treatment is referred to as secondary
treatment. Advanced secondary
treatment usually involves applying
chemical systems in addition to
biological ones, such as injecting
chlorine to disinfect the water.
Tertiary treatment methods are
sometimes used after primary and
secondary treatment to remove traces
of chemicals and dissolved solids.
METHODS OF RECYCLING WATER
• Water that has been poured in cups and not
drank or water bottles with water in them
already can be re-used. Simply boil the water to
kill any germs and can be used for drinking
water. If this method does not sound kosher, the
water could also be used to water house plants.
And the plastic bottles can be used in the garden
as miniature water irrigation systems.
• Re-use water that drains out of flower pots.
Depending on the size of the pot, simply place a
plastic plate or bucket under the flower pot and
any water that drains out can be re-used in the
• Save kitchen water. Water used to clean dishes
can be dumped in the toilet bowl for flushing.
Water used to cook vegetables or pasta with
can be into the compost pile or in garden.
How Can Water Recycling Benefit Us?
Water recycling provides enormous
Water recycling decreases the extraction
of water form sources that may be
dwindling and may stop being viable as
habitats for valuable and endangered
Recycling wastewater can decrease the
discharge of effluents that may damage and
pollute the ecosystems of the sensitive
bodies of water.
Recycled water can be used to create new
wetlands or to enhance and improve the
quality of existing ones.
Water recycling can reduce and prevent
pollution by leaving damaging pollutants at
the treatment plant.
WHAT IS SUSTAINABLE DEVELOPMENT?
Sustainable development is
development that meets the needs
and aspirations of the current
generation without compromising
the ability to meet those of future
Sustainable development ties
together concern for the carrying
capacity of natural systems with
the social and economic challenges
faced by humanity. It is important
because it emphasizes towards a
greater drive to equality and
elevation of poverty. It shows the
importance of economic, social and
Groundwater is water
that exists in the pore
spaces and fractures
in rock and sediment
beneath the Earth's
surface. It originates
as rainfall or snow,
and then moves
through the soil into
system, where it
eventually makes its
way back to surface
streams, lakes, or
WAYS TO PROTECT AND
• Dispose of chemicals
• Take used motor oil to a
• Limit the amount of
fertilizer used on plants.
• Run full loads of dishes
• Take short showers.
• Abandon all
are not needed.
WHY IS WATER CONSERVATION
• Conserving water can also save energy which reduces
your carbon footprint and helps the country become
more energy independent.
• One of the reasons is to prevent water pollution and
avert using huge amounts of money to recycle, clean and
purify the water.
• Conserving the water prevents water shortages and helps
build a better defense against future drought years.
Rainwater harvesting is the process of
collecting, filtering and storing water from
roof tops, paved and unpaved areas for
multiple uses . The surplus water after usage
can be used for recharging ground
water aquifer through artificial recharge
techniques. This can also result in improving
the quality of the ground water e.g. lower
fluoride content in ground water. Rainwater
harvesting mechanisms are designed after
assessing the site conditions such as incident
rainfall, subsurface strata and their storage
characteristics, infiltration test and by
building suitable structures to collect and
Watershed management is an adaptive , comprehensive,
integrated multi resource management planning
process that seeks to balance healthy ecological,
economic, and cultural/social conditions within a
Watershed management provides a framework for
integrated decision-making to help: assess the nature
and status of the watershed; identify watershed issues;
define and re-evaluate short and long-term objectives,
actions and goals; assess benefits and costs; and
implement and evaluate actions.
NARMADA BACHAO ANDOLAN
Narmada Bachao Andolan is the most powerful mass
movement, started in 1985, against the construction of huge
dam on the Narmada river. The proposed Sardar Sarovar
Dam and Narmada Sagar will displace more than 250,000
people. Narmada Bachao Andolan or save Narmada movement
is a Non Governmental Organisation(NGO) that mobilised
people, farmers, environmentalists, and human rights
activists against the Sardar Sarovar Dam built across the
Narmada river in Gujarat. Narmada is the India's largest
west flowing river, which supports a large variety of people
with distinguished culture and tradition ranging from the
indigenous (tribal) people inhabited in the jungles here to
the large number of rural population.
HISTORY OF THE DAM
It is a multi crore project that will generate a big revenue for
the government. The Narmada Valley Development plan is the
most promised and most challenging plan in the history of India.
The proponents are of the view that it will produce 1450 MW of
electricity and pure drinking water to 40 million people covering
thousand of villages and towns. Some of the dams have been
already been completed such as Tawa and Bargi Dams. But the
opponents says that this hydro project will devastate human lives
and bio diversity by destroying thousand of acres of forests and
agricultural land. On the other hand it will overall deprive
thousands of people of their livelihood. They believe that the
water and energy could be provided to the people through
alternative technological means, that would be ecologically
Led by one of the prominent leader Medha Patkar, it has now
been turned into the International protest, gaining support
from NGO'S all around the globe. Protestors are agitating the
issue through the mass media, hunger strikes, massive
marches, rallies and the through the on screen of
several documentary films. Although they have been protesting
peacefully, but they been harassed, arrested and beaten up by
the police several times. The Narmada Bachao Andolan has
been pressurizing the world bank to withdraw its loan from the
project through media. The strong protests through out the
country not only made impact on the local people but has also
influenced the several famous celebrities like film star Aamir
Khan , who has made open efforts to support Narmada Bachao
Andolan. He said he only want that those who have been
rendered homeless should be given a roof.
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