2. HYDRO POwER
Hydro-power or water power is power derived from
the energy of falling water and running water, which
may be harnessed for useful purposes. Kinetic energy of
flowing water (when it moves from higher potential to
lower potential) rotates the blades/propellers of turbine,
which rotates the axle. The axle has a coil which is placed
between the magnets. When the coils rotate in magnetic
field it induce them in the coil due to change in flux.
Hence, kinetic energy of flowing water is converted to
electrical energy.
3. HYDRO POwER
Since ancient times, hydro-power has been used for irrigation and the
operation of various mechanical devices, such
as watermills, sawmills, textile mills, dock cranes, domestic lifts, power
houses and paint making.
Since the early 20th century, the term has been used almost
exclusively in conjunction with the modern development of hydroelectric power, which allowed use of distant energy sources. Another
method used to transmit energy used a trompe, which produces
compressed air from falling water. Compressed air could then be piped
to power other machinery at a distance from the waterfall. Hydro power
is a renewable energy source.
Water's power is manifested in hydrology, by the forces of water on
the riverbed and banks of a river. When a river is in flood, it is at its
most powerful, and moves the greatest amount of sediment. This higher
force results in the removal of sediment and other material from the
riverbed and banks of the river, locally causing erosion, transport and,
with lower flow, sedimentation downstream.
4. USES Of HYDRO POwER
•A primary use of hydropower energy is to produce electricity. The main ingredients of
hydroelectric power plants are dams, rivers and turbines. Plants use dams to create reservoirs
where the water is stored. This water is then released through turbines and spun to activate
generators and create electricity. The first hydropower electrical systems were developed in the
19th century and used direct current technology to light Michigan theaters and shops.
America also spearheaded the use of alternating current technology in the world's first
hydroelectric plant in Wisconsin in 1882. One of the major advantages of hydropower plants
to the wider community is that by law the facilities must be open to the public, and many
plants offer a wide range of recreations including swimming, fishing and boating. The
largest American operator of hydroelectric power plants is the U.S. Army Corps of Engineers.
The Corps's 75 bases have an installed capacity of 23,764 megawatts -- that's 24 percent of
the nation's electricity output. The Corps is also the biggest federal operator of outdoor leisure
activities in the country, providing 33 percent of all freshwater fishing opportunities and 15
percent of boating facilities. There are thousands of boat launch ramps and 20 annual
fishing tournaments at their largest parks and lakes. The Army Corps is also committed to
preserving a healthy stock of fish.
5. ImPORTANT HYDRO POwER
STATIONS IN INDIA
Narora Atomic Power Station
Rajasthan Atomic Power Station
Tarapur Atomic Power Station
Kakrapar Atomic Power Station
Madras Atomic Power Station
Kaiga Nuclear Power Plant
Madras Atomic Power Station
6.
7. Water recycling is a generic term for water reclamation and reuse, where the resulting water is
referred to as recycled water. This term will be used throughout this document, but you might also
find a number of other terms used in the water industry. These include:
• Water reclamation
• Water recycling
• Water reuse
• Wastewater
• Sewage effluent
• Reclaimed water
• Grey water
8. .
Physical processes are the first step in the water recycling process. Raw sewage passes through bar screens
which are simply metal rods immersed in the influent flow to separate large objects such as sticks and rags
from the water. They are used to protect pumps and other rotating mechanisms further in the treatment
process. After the water passes through bar screens, it enters a grit chamber. Here the influent flow is
slowed so that sand and gravel simply fall to the bottom of the chamber. Primary clarifiers allow further
slowing of the wastewater so that settle able organics precipitate to the bottom while fats, oils, and greases
float to the top. These physical processes remove approximately half of the contaminants in wastewater
9. The cost of reclaimed water exceeds that of potable water in many regions of the world, where
a fresh water supply is plentiful. However, reclaimed water is usually sold to citizens at a cheaper
rate to encourage its use. As fresh water supplies become limited from distribution costs, increased
population demands, or climate change reducing sources, the cost ratios will evolve also.
Using reclaimed water for non-potable uses saves potable water for drinking, since less potable
water will be used for non-potable uses.
It sometimes contains higher levels of nutrients such as nitrogen, phosphorus and oxygen which may
somewhat help fertilize garden and agricultural plants when used for irrigation.
The usage of water reclamation decreases the pollution sent to sensitive environments. It can also
enhance wetlands, which benefits the wildlife depending on that eco-system.
11. Water Conservation
Water can be conserved mainly in two
ways
Rainwater Harvesting
Watershed Management System
12.
Rainwater
harvesting
Rainwater harvesting is the accumulation and deposition of
rainwater for reuse before it reaches the aquifer. Uses include
water for garden, water for livestock, water for irrigation, and
indoor heating for houses etc.. In many places the water collected
is just redirected to a deep pit with percolation. The harvested
water can be used as drinking water as well as for storage and
other purpose like irrigation.
Advantages
Rainwater harvesting provides an independent water supply during regional
water restrictions and in developed countries is often used to supplement the
main supply. It provides water when there is a drought, prevents flooding of
low-lying areas, replenishes the ground water level, and enables dug wells and
bore wells to yield in a sustained manner. It also helps in the availability of
clean water by reducing the salinity and the presence of iron salts.
Makes use of a natural resource and reduces flooding, storm water , erosion,
and contamination of surface water with pesticides, sediment, metals,
and fertilizers.
13. In the state of Tamil Nadu, rainwater harvesting was made compulsory for every
building to avoid ground water depletion. It proved excellent results within five
years, and every other state took it as role model. Since its
implementation, Chennai saw a 50 percent rise in water level in five years and the
water quality significantly improved.
In Rajasthan, rainwater harvesting has traditionally been practiced by the people
of the Thar Desert. There are many ancient water harvesting systems in
Rajasthan, which have now been revived Water harvesting systems are widely
used in other areas of Rajasthan as well, for example the chauka system from
the Jaipur district.
At present, in Pune(in Maharashtra), rainwater harvesting is compulsory for any
new society to be registered.
An attempt has been made at Dept. of Chemical Engineering, IISc, Bangalore to
harvest rainwater using upper surface of a solar still, which was used for water
distillation
14. Watershed
management
Watershed management is the study of the relevant characteristics of a watershed aimed
at the sustainable distribution of its resources and the process of creating and
implementing plans, programs, and projects to sustain and enhance watershed functions
that affect the plant, animal, and human communities within a watershed boundary
.Features of a watershed that agencies seek to manage include water supply, water
quality, drainage, storm water runoff, water right, and the overall planning and
utilization of watersheds. Landowners, land use agencies , storm water management
experts, environmental specialists, water use surveyors and communities all play an
integral part in the management of a watershed.
16.
Sustainable development
Sustainable development is an organising
principle for human life on a finite planet. It posits a
desirable future state for human societies in which living
conditions and resource-use meet human needs without
undermining the sustainability of natural systems and
the environment, so that future generations may also
meet their needs.
Sustainable development ties together concern for
the carrying capacity of natural systems with the social
and economic challenges faced by humanity. As early as
the 1970s, 'sustainability' was employed to describe
an economy "in equilibrium with basic ecological support
systems."Scientists in many fields have highlighted The
Limits to Growth and economists have presented
alternatives, for example a 'steady state economy to
address concerns over the impacts of expanding human
development on the planet.
The term 'sustainable development' rose to significance
after it was used by the Brundtland Commission in its
1987 report Our Common Future. In the report, the
commission coined what has become the most oftenquoted definition of sustainable development:
"development that meets the needs of the present without
compromising the ability of future generations to meet
their own needs."
The concept of sustainable development has in the past
most often been broken out into three constituent
domains: environmental sustainability, economic
sustainability and social sustainability. However, many
other possible ways to delineate the concept have been
suggested. For example, distinguishing the four domains
of economic, ecological, political and cultural
sustainability.[Other important sources refer to the fourth
domain as 'institutional' or as 'good governance.'
17. SuStAINABIlIty Of
GrOuNDwAtEr
Groundwater provides a significant proportion of
rural dwellers in the developing countries with access
to safe drinking water and will continue to do so in
the future. Groundwater is fairly ubiquitous, but its
conditions vary enormously and exploitation is often
undertaken with limited understanding of
hydrogeology and without sufficient evaluation of
the resource. In some places, heavy water use for
agriculture has led to over-abstraction and placed
groundwater out of the reach of domestic users as
water tables have fallen. There are also regions where
groundwater quality is not fit for human
consumption (e.g. due to a high level of arsenic,
fluoride, iron or nitrates, or contamination from
human impacts such as poor sanitation, oil spills or
chemicals).
The objective of the Sustainable Groundwater
Development theme is: Groundwater resources are
properly considered and sustainably used for
developing drinking water supply sources. The theme
has three sub-topics:
Hand pump Technology
Cost Effective Boreholes (includes machine drilling
and manual drilling)
Cost Effective Water Resource Management
19. Narmada Bachao Andolan (NBA) is a social
movement consisting
of adivasis, farmers environmentalists, and human
rights activists against a number of large dams being
built across the Narmada river. The river flows
through the states of Gujarat, , and Madhya Pradesh
in India. Sardar Sarovar Dam in Gujarat is one of the
biggest dams on the river and was one of the first
focal points of the movement. Friends of River
Narmada is the unofficial website of the NBA.
Their mode of campaign includes hunger strikes and
garnering support from film and art personalities
(notably Bollywood actor Aamir Khan). Narmada
Bachao Andolan, with its leading
spokespersons Medha Patkar and Baba Amte, received
20. Through Patkar's channel of communication between the government and the residents,
she provided critiques to the project authorities and the governments involved. At the same
time, her group realized that all those displaced were only given compensation for the
immediate standing crop and not for displacement and rehabilitation.
As Patkar remained immersed in the Narmada struggle, she chose to quit her Ph.D.
studies and focus entirely on the Narmada activity. Thereafter, she organized a 36-day
solidarity march among the neigh boring states of the Narmada valley from Madhya
Pradesh to the Sardar Sarovar dam site. She said that the march was "a path symbolizing
the long path of struggle (both immediate and long-term) that [they] really had". The
march was resisted by the police, who according to Patkar were "caning the marchers and
arresting them and tearing the clothes off women activists".
There were groups such as Gujarat-based Arch-Vahini (Action Research in Community
Health and Development) and Narmada Asargrastha Samiti (Committee for people
affected by the Narmada dam), Madhya Pradesh-based Narmada Ghati Nav Nirman
Samiti (Committee for a new life in the Narmada Valley) and Maharashtra-based
Narmada Dharangrastha Samiti (Committee for Narmada dam-affected people) who either
believed in the need for fair rehabilitation plans for the people or who vehemently opposed
dam construction despite a resettlement policy.
While Medha Patkar established Narmada Bachao Andolan in 1989, all these groups
joined this national coalition of environmental and human rights activists, scientists,
academics and project-affected people with a non-violent approach.
21. OUTCOME OFTHE ANDOLAN
The Supre me Co urt's de cisio n is still pe nding , se e king sto ppag e o f co nstructio n o f the Sardar Saro var dam.
The co urt initially rule d the de cisio n in the A lan's favo r, the re by e ffe cting an imme diate sto ppag e o f wo rk
ndo
at the dam and dire cting the co nce rne d state s to first co mple te the re habilitatio n and re place me nt pro ce ss.
The Co urt de libe rate d o n this issue furthe r fo r se ve ral ye ars but finally uphe ld the Tribunal A
ward and
allo we d the co nstructio n to pro ce e d, subje ct to co nditio ns. The co urt intro duce d a me chanism to mo nito r the
pro g re ss o f re se ttle me nt pari pass with the raising o f the he ig ht o f the dam thro ug h the Grie vance Re dre ssal
A ritie s (GRA in e ach o f the party state s. The co urt’ s de cisio n re fe rre d in this do cume nt, g ive n in the ye ar
utho
)
20 0 0 afte r se ve n ye ars o f de libe ratio ns, has pave d the way fo r co mple ting the pro je ct to attain full e nvisag e d
be ne fits. The co urt's final line o f the o rde r state s, " Eve ry e nde avo ur shall be made to se e that the pro je ct is
co mple te d as e xpe ditio usly as po ssible " . [1 3]
Subse q ue nt to the co urt’ s ve rdict, Pre ss I rmatio n B au (PI ) fe ature d an article which state s that:
nfo
ure
B
" The N
armada B
achao A lan has re nde re d a ye o man's se rvice to the co untry by cre ating a hig h-le ve l o f
ndo
aware ne ss abo ut the e nviro nme ntal and re habilitatio n and re lie f aspe cts o f Sardar Saro var and o the r
pro je cts o n the N
armada. B afte r the co urt ve rdict it is incumbe nt o n it to ado pt a ne w ro le . I ad o f
ut,
nste
'damning the dam' any lo ng e r, it co uld assume the ro le o f vig ilant o bse rve r to se e that the re se ttle me nt wo rk
is as humane and painle ss as po ssible and that the e nviro nme ntal aspe cts are take n due care o f. "
23. Hardwater
Hard water is water that has high mineral content (in contrast with "soft
water").
Hard drinking water is generally not harmful to one's health, but can pose
serious problems in industrial settings, where water hardness is
monitored to avoid costly breakdowns in boilers, cooling towers, and
other equipment that handles water. In domestic settings, hard water is
often indicated by a lack of suds formation when soap is agitated in
water, and by the formation of lime scale in kettles and water heaters.
Wherever water hardness is a concern, water softening is commonly
used to reduce hard water's adverse effects.
24. Soft water
Water softening is the removal
of calcium, magnesium, and certain other
metal cations in hard water. The resulting
soft water is more compatible with soap and
extends the lifetime of plumbing. Water
softening is usually achieved using lime
softening or ion-exchange resins.
The presence of certain metal ions in water
causes a variety of problems. These ions
interfere with the action of soaps. They also
lead to build up of lime scale, which can
foul plumbing, and promote galvanic
corrosion . In industrial scale water
softening plants, the effluent flow from the
re-generation process can precipitate scale
that can interfere with sewage systems.
25. Types Of Hardness
Temporary Hardness
Temporary hardness is a type of water hardness caused by the presence
of dissolved bicarbonate minerals (calcium bicarbonate and magnesium bicarbonate). 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 sulphate and chloride compounds, this "temporary" hardness
can be reduced either by boiling the water, or by the addition of lime (calcium hydroxide) through the
softening process of lime softening
Permanent Hardness
Permanent hardness is hardness (mineral content) that cannot be removed by boiling. When
this is the case, it is usually caused by the presence of calcium sulphate and/or magnesium
sulphates 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 exchange column .
Total Permanent Hardness = Calcium Hardness + Magnesium Hardness The calcium and
magnesium hardness is the concentration of calcium and magnesium ions expressed as
equivalent of calcium carbonate . Total permanent water hardness expressed as equivalent of
CaCO3 can be calculated with the following formula: Total Permanent Hardness (CaCO 3) =
2.5(Ca2+) + 4.1(Mg2+)
26. Effects of hard water
Hard water also forms deposits that clog plumbing.
These deposits, called "scale", are composed mainly
of calcium carbonate (CaCO3), magnesium
hydroxide (Mg(OH)2), and calcium sulphate (CaSO 4).
Calcium and magnesium carbonates tend to be
deposited as off-white solids on the inside surfaces of
pipes and heat exchangers. This precipitation
(formation of an insoluble solid) is principally caused
by thermal decomposition of bicarbonate ions but also
happens to some extent even without such ions. The
resulting build-up of scale restricts the flow of water in
pipes. In boilers, the deposits impair the flow of heat into
water, reducing the heating efficiency and allowing
the metal boiler components to overheat. In a
pressurized system, this overheating can lead to failure
of the boiler.[ The damage caused by calcium carbonate
deposits varies on the crystalline form, for
example, calcite or aragonite.
The presence of ions in an electrolyte, in this case, hard
water, can also lead to galvanic corrosion, in which one
metal will preferentially corrode when in contact with
another type of metal, when both are in contact with an
electrolyte. The softening of hard water by ion
exchange does not increase its corrosivity per se.
Similarly, where lead plumbing is in use, softened
water does not substantially increase plumbo-solvency.
