Water Services:Introduction Water treatment Demineralization Cold-water services Hot-water services Pipe sizing Materials for water services water supply sanitation Drain systems

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TOPIC: WATER SERVICES
Subject : Building Service Engineering
Branch : Computer Technology
Sr. No Name Roll No. Section Registration No.
1. Apeksha Kharwal 102 B 19010897
2. Aman Kapse 84 A 19010785
3. Rutweek Duragkar 67 A 18011010
4. Tanmay Patil 73 A 19010813
5. Anushka Kherde 5 A 19010275

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Contents
 Introduction
 Water treatment
 Demineralization
 Cold-water services
 Hot-water services
 Pipe sizing
 Materials for water services
 water supply sanitation
 Drain systems.

3. INTRODUCTION
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4. DTEL
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Sewerage service
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What is a Water Service
Why are water services licensed?
Water supply
Irrigation System Repairs
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Drainage services
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What is a Water Service
A water service is the provision of any of the following services through
reticulated piping, conduits and approved infrastructure.
The services include:
 Water supply service – supply of potable or non-potable water
 Sewerage service – collection, treatment and disposal of sewage
 Irrigation service – provision of water for irrigation for agriculture or
pasture
 Drainage service – management of stormwater, groundwater, surface
water or soil salinity, which may include managing the quality of the
water

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Why are water services licensed?
The main reason for licensing is to promote and create an effective,
efficient and sustainable water services industry. It also exists to
prevent water service providers from abusing their power and
making sure customers are provided with good quality services.
The licensing scheme also sets out minimum service and technical
standards and requires the monitoring of asset management
practices.
It also ensures that industry participants have the financial and
technical capacity necessary to provide water services.

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Water supply
Water supply is the provision of water by public utilities, commercial organizations
, community endeavors or by individuals, usually via a system of pumps and pipes.
Public water supply systems are crucial to properly functioning societies. These
systems are what supply drinking water to populations around the
globe.[1] Aspects of service quality include continuity of supply, water quality and
water pressure. The institutional responsibility for water supply is arranged
differently in different countries and regions (urban versus rural). It usually
includes issues surrounding policy and regulation, service provision and
standardization.
Water supply is a separate topic from irrigation, the practice and systems of water
supply on a larger scale, for a wider variety of purposes, primarily agriculture.

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Water Supply System

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Sewerage service
Sewerage (or sewage system) is the infrastructure that
conveys sewage or surface
runoff (stormwater, meltwater, rainwater) using sewers. It
encompasses components such as
receiving drains, manholes, pumping stations, storm
overflows, and screening chambers of the combined
sewer or sanitary sewer. Sewerage ends at the entry to
a sewage treatment plant or at the point of discharge into
the environment. It is the system of pipes, chambers,
manholes, etc. that conveys the sewage or storm water.

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Sewerage System

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Irrigation System Repairs
Irrigation systems require a little TLC to keep working efficiently and effectively.
Neglected systems can lead to both dry lawns and landscapes as well as properties
that are saturated with water, wasting this precious resource. That is where Conserva
Irrigation comes in.
Conserva Irrigation’s free Comprehensive system inspection pinpoints any issues
your system may have, be it leaks in the water lines, control issues, etc. We’ll explain
each piece and let you know how we can repair it.
Some irrigation repairs can be done on the spot. Larger repairs may require a second
trip, but as your irrigation specialists, we’re happy to do it. Our goal is to provide our
clients with a beautiful, green property that minimizes water waste, and we stand by
that.

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Irrigation System

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Drainage services
Andel drainage service teams are highly trained, experienced and
vehicles are equipped with state-of-the-art equipment which means we
can resolve any drainage problems quickly, efficiently and cost-effectively.
It is our philosophy that prevention is always better than cure and regular
maintenance packages are available for those customers who require a
planned and preventative maintenance programme to ensure large area
drainage systems are maintained in good working order.
All Andel products and services are fully compliant with current legislation
and guidelines. We inspect and certify, we carry out full drainage trace
surveys and mapping (as required by the emergency services) as well as
drain condition surveys and can carry out any remedial work required.

14. Water treatment
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Process, Chemical, Physical, Biological, Portable
water purification
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Softening, De-alkalization
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Water treatment
Drinking water treatment
Combined dealkalisation + softening, Decationisation
5
Demineralisation, Nitrate removal
6
Selective removal of various other contaminants
7

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Water treatment
Water treatment is any process that improves
the quality of water to make it appropriate for a specific end-use.
The end use may be drinking, industrial water supply, irrigation,
river flow maintenance, water recreation or many other uses,
including being safely returned to the environment. Water
treatment removes contaminants and undesirable components, or
reduces their concentration so that the water becomes fit for its
desired end-use. This treatment is crucial to human health and
allows humans to benefit from both drinking and irrigation use.

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Water Treatment

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Drinking water treatment
Treatment for drinking water production involves the removal of contaminants and/or
inactivation of any potentially harmful microbes from raw water to produce water that
is pure enough for human consumption without any short term or long term risk of any
adverse health effect. In general terms, the greatest microbial risks are associated with
ingestion of water that is contaminated with human or animal (including bird) faeces.
Faeces can be a source of pathogenic bacteria, viruses, protozoa and helminths. The
removal or destruction of microbial pathogens is essential, and commonly involves the
use of reactive chemical agents such as suspended solids, to
remove bacteria, algae, viruses, fungi, and minerals including iron and manganese.
Research including Professor Linda Lawton's group at Robert Gordon University,
Aberdeen is working to improve detection of cyanobacteria.These substances continue
to cause great harm to several less developed countries who do not have access to
effective water purification systems.

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Processes
The processes involved in removing the contaminants include physical processes such
as settling and filtration, chemical processes such as disinfection and coagulation, and
biological processes such as slow sand filtration.
A combination selected from the following processes (depending on the season and
contaminants and chemicals present in the raw water) is used for municipal drinking
water treatment worldwide.
Chemical
Pre-chlorination for algae control and arresting biological growth.
 Aeration along with pre-chlorination for removal of dissolved iron when present
with relatively small amounts of manganese.
 Disinfection for killing bacteria, viruses and other pathogens, using chlorine, ozone
and ultra-violet light.

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Physical
 Sedimentation for solids separation that is the removal of suspended solids trapped in the floc.
 Filtration to remove particles from water either by passage through a sand bed that can be
washed and reused or by passage through a purpose designed filter that may be washable.
 Dissolved air flotation to remove suspended solids.
Physico-chemical
Also referred to as "Conventional" Treatment
 Coagulation for flocculation.
 Coagulant aids, also known as polyelectrolytes – to improve coagulation and for more robust
floc formation.
 Polyelectrolytes or also known in the field as polymers, usually consist of either a positive or
negative charge. The nature of the polyelectrolyte used is purely based on the source water
characteristics of the treatment plant.
 These will usually be used in conjunction with a primary coagulant such as ferric chloride, ferric
sulfate, or alum.

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Biological
Slow sand filtration using a biofilm to metabolize organic matter,
adsorb soluble components and entrap particulates.
Portable water purification
Living away from drinking water supplies often requires some form
of portable water treatment process. These can vary in complexity
from the simple addition of a disinfectant tablet in a hiker's water
bottle through to complex multi-stage processes carried by boat or
plane to disaster areas.

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Constituent Unit processes
Turbidity and
particles
Coagulation/ flocculation, sedimentation, granular
filtration
Major dissolved
inorganics
Softening, aeration, membranes
Minor dissolved
inorganics
Membranes
Pathogens Sedimentation, filtration, disinfection
Major dissolved
organics
Membranes, adsorption

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The ion exchange technology is used for different
water treatment applications:
 Softening (removal of hardness)
 De-alkalisation (removal of bicarbonate)
 Decationisation (removal of all cations)
 Combined dealkalisation and softening
 Demineralisation (removal of all ions)
 Mixed bed polishing
 Nitrate removal
 Selective removal of various contaminants

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Softening
Natural water contains calcium and magnesium ions (see water analysis) which
form salts that are not very soluble. These cations, together with the less
common and even less soluble strontium and barium cations, are called
together hardness ions. When the water evaporates even a little, these cations
precipitate. This is what you see when you let water evaporate in a boiling
kettle on the kitchen stove.
Hard water also forms scale in water pipes and in boilers, both domestic and
industrial. It may create cloudiness in beer and soft drinks. Calcium salts
deposit on the glasses in your dishwasher if the city water is hard and you have
forgotten to add salt.
Strongly acidic cation exchange resins (SAC, see resin types) used in the sodium
form remove these hardness cations from water. Softening units, when loaded
with these cations, are then regenerated with sodium chloride (NaCl, table
salt).

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Reactions
Here the example of calcium:
2 R-Na + Ca++ R2-Ca + 2 Na+
R represents the resin, which is initially in the sodium form. The reaction for magnesium
is identical.
The above reaction is an equilibrium. It can be reversed by increasing the sodium
concentration on the right side. This is done with NaCl, and the regeneration reaction is:
R2-Ca + 2 Na+ 2 R-Na + Ca++

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SAC (Na)
Raw water Softened water
The water salinity is unchanged, only the hardness has been replaced by sodium. A
small residual hardness is still there, its value depending on regeneration conditions.
What happens to the water

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Uses
Examples for the use of softeners:
 Treatment of water for low pressure boilers
 In Europe, most dishwashers have a softening cartridge at the bottom of the
machine
 Breweries and soft drink factories treat the water for their products with food
grade resins
Softening the water does not reduce its salinity: it merely removes the hardness ions
and replaces them with sodium, the salts of which have a much higher solubility, so
they don't form scale or deposits.

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De-alkalization
This particular process uses a weakly acidic cation resin. This resin type is capable of
removing hardness from water when it also contains alkalinity. After treatment, the
water contains carbon dioxide, that can be eliminated with a degasifier tower. The
cation resin is very efficiently regenerated with an acid, usually hydrochloric acid.
Reactions
Here the example of calcium:
2 R-H + Ca++(HCO3
–)2 R2-Ca + 2 H+ + 2 HCO3
–
and the hydrogen cations combine with the birarbonate anions to produce
carbon dioxide and water:
H+ + HCO3
– CO2 + H2O

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Raw water Decarbonated water
What happens to the water
WAC (H)

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Uses
De-alkalisation is used:
 In breweries
 In household drinking water filters
 For low pressure boilers
 As a first step before the SAC exchange in demineralization
De-alkalisation reduces the salinity of water, by removing hardness cations
and bicarbonate anions.

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Combined dealkalisation + softening
This process is sometimes called Carbomix, although the resins are
not mixed. It uses two resins in series, a WAC in the H+ form
followed by a SAC in the Na+ form. Both resins can be put as a
Stratabed in a single colum, or in two separate units. This is useful
only when the hardness is greater than alkalinity (in meq/L)
otherwise the WAC resin will do the job alone.
The reactions are shown in the sections above on de-alkalisation
and softening and will not be repeated here. For the process to be
efficient, de-alkalisation must take place first

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The second step is softening of the residual (permanent) hardness. The produced
CO2 can be degassed:
SAC ( Na)
WAC (H)
Regeneration is done in two steps, first with acid (preferably HCl) then with brine.
DEG
What happens to the water
The first step is dealkalisation:

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Decationisation
The removal of all cations is seldom practiced, except as a first stage of the
demineralisation process, or sometimes in condensate polishing where the
decationiser precedes a mixed bed unit. A strongly acidic cation exchange
resin (SAC) is used in the H+ form.
Reactions
Here the example of sodium, but all cations react in the same way:
R-H + Na+ R-Na + H+
The equilibrium reaction is reversed for regeneration by increasing the
hydrogen concentration on the right side. This is done with a strong acid, HCl or
H2SO4:
R-Na + H+ R-H + Na+

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Demineralisation
For many applications, all ions in the water must be removed. In particular, when water is
heated to produce steam, any impurity can precipitate and cause damage. As there are
cations and anions in the water, we must use two different types of resins: a cation
exchanger and an anion exchanger. This combined arrangement produces pure water, as
presented in the general introduction. Demineralisation is also called deionisation. The
cation resin is used in the hydrogen form (H+) and the anion resin in the hydroxyl form (OH–
), so that the cation resin must be regenerated with an acid and the anion resin with an
alkali.
A degasifier is used to remove the carbon dioxide created after cation exchange when the
water contains a significant concentration of bicarbonate.
The cation resin is usually located before the anion resin: otherwise if the water contains
any hardness, it would precipitate in the alkaline environment created by the OH— form
anion resin as Ca(OH)2 or CaCO3, which have low solubility.

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Mixed bed polishing
The last traces of salinity and silica can be removed on a resin bed where highly regenerated strong acid
cation and strong base anion resins are mixed.
Mixed bed units deliver an excellent treated water quality, but are complcated to regenerate, as the resins
must first be separated by backwashing before regeneration. Additionally, they require large amounts of
chemicals, and the hydraulic conditions for regeneration are not optimal. Therefore, mixed beds are
usually only used to treat pre-demineralised water, when the service run is long.
Mixed bed unit in service and in regeneration

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Capacity and throughput
The schema and treated water quality shown above apply to
polishers installed downstream of an ion exchange primary
demineralisation system. The feed water to the polishing unit, in
this case, contains only traces of sodium and silica. The operating
capacity is usually limited by the anion resin, and is very low.
However, the running time for a feed water having a conductivity of
1 µS/cm is usually 2 to 4 weeks.
When the polisher is fed with water containing other ions, such as
after a reverse osmosis plant, the situation is completely different.
RO permeates often contain a relatively high proportion of carbon
dioxide, and this is then the limiting factor. The treated water quality
here may have a conductivity higher than 0.1 µS/cm (but not more
than 1 µS/cm) and the throughput is only one or a few days.

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Uses
 Treatment of water pre-demineralised with ion exchange resins
 Polishing of reverse osmosis permeate
 Polishing of sea water distillate
 Treatment of turbine condensate in power stations
 Treatment of process condensate in various industries
Production of ultra-pure water for the semiconductors industry

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Nitrate removal
Nitrate can be removed selectively from drinking water using strong base anion resins
in the chloride cycle, i.e. regenerated with a NaCl brine. The reaction is:
RSBA-Cl + NO3
– RSBA-NO3 + Cl–
Raw water Denitrated water
SBA (Cl)

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Selective removal of various other contaminants
Selective removal of metals and other contaminants is mainly used for drinking water and
for waste. Many of these applications require special resins: chelating resin making stable
metal complexes, for instance.
Examples
 Removal of boron (boric acid) from drinking water
 Removal of nitrate from drinking water (shown above)
 Removal of perchlorate from drinking water
 Removal of heavy metals from waste: Cd, Cr, Fe, Hg, Ni, Pb, Zn
In many of these applications, a residual concentration in the µg/L range is possible.
Some contaminants are difficult to remove with ion exchange, due to a poor selectivity of
the resins. Examples: As, F, Li. See the periodic system of the elements with some ion
exchange data. See also the page about resin types (selective resins) and a separate page
about ion exchange processes for drinking water.

41. Demineralization
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3
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Demineralization ( DM ) Water Treatment Plants
Principle
Process
4 Advantages

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Demineralization ( DM ) Water Treatment
Plants
Demineralization is the process of removing mineral salts from Water by using the
ion exchange process.
Demineralised Water is Water completely free ( or almost ) of dissolved minerals
as a result of one of the following processes :
 Distillation
 Deionization
 Membrane filtration (reverse osmosis or nanofiltration)
 Electrodyalisis
 Or other technologies.

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Principle
Raw Water is passed via two small polystyrene bead filled (ion exchange resins)
beds. While the cations get exchanged with hydrogen ions in first bed, the
anions are exchanged with hydroxyl ions, in the second one.
Process
In the context of Water purification, ion-exchange is a rapid and reversible
process in which impurity ions present in the Water are replaced by ions
released by an ion-exchange resin. The impurity ions are taken up by the resin,
which must be periodically regenerated to restore it to the original ionic form.
(An ion is an atom or group of atoms with an electric charge. Positively-charged
ions are called cations and are usually metals; negatively-charged ions are called
anions and are usually non-metals).

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The following ions are widely found in raw Waters :
Cations
 Calcium (Ca2+)
 Magnesium (Mg2+)
 Sodium (Na+)
 Potassium (K+)
Anions
 Chloride ( Cl-)
 Bicarbonate (HCO3-)
 Nitrate (NO3-)
 Carbonate (CO32-)

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Advantage
 Variety of cost effective standard models.
 Improved aesthetics and rugged design.
 User friendly, low maintenance and easy to install.
 Simpler distribution and collection systems.
 Quick availability.
 Pre dispatch assembly check.
 The multiport valves are top mounted as well as side mounted with the
necessary high pressure rating PVC piping.
 Single valve operation as compared to the six valves in conventional filters
 Each operating step is clearly marked on the valve, thereby eliminating chances
of error in the operating sequence.
 Single valve assembly, with its simplified frontal Piping, simpler distribution
collecting systems is Very easy to install.
 Rust free
 Less power consumption

48. Water Supply Systems
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1
2
3
Types Of Cold Water System
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Water Supply Systems
Hot water system
Cold water system

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Water Supply Systems
• Cold water system
• Hot water system
Cold water system provide water for the following purposes.
• Drinking purpose
• Cooking purpose
• Sanitary purpose
• Washing purpose
• Gardening
Types Of Cold Water System
Two Types
1. Direct system
2. Indirect systemDirect Water Supply System
Water is supplied direct from mains to fixtures
Indirect Water SupplyOutsideSystemWater going to overhead tank and then
the water is supplied to different floorsby gravity

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Direct Water Supply System
Advantages: saving in pipe work especially in multi story buildings. This is
due to cold water distribution pipe from the cistern being omitted Fresh
Drinking water may be obtained at any point
Disadvantages: There is a danger of foul water from the sanitary fittings
being siphoned back into the main water During peak periods there is a
tendency for the lowering of pressure If there is a mains burst there is no
store of water
Indirect Water Supply System
Advantages: There is no risk of back siphon age with this system. There is
no tendency of pipe bursting due to the low pressure in the pipe work In
case of an interruption in the mains supply there is an adequate store of
water
Disadvantages: Longer pipe runs are required A larger storage cistern is
necessary Fresh Drinking water is only available at the kitchen sink (or
single point)

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Parts of water distribution system

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Pipe Sizing

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Pipe Sizing
Introduction: The chemical process industry is involved in many
operations, for different types of fluids, with different applications.
Though in principle, various guidelines and formulae are available for
pipeline sizing for different services. Hence it becomes critical at times
conceptualization is necessary before deciding design parameters.
When fluids are to be carried from one place to another in household
piping to cross country pipeline, piping and fitting constitutes a high
cost. The size of piping plays an important role in the pumping cost.

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Pipeline Sizing: In any chemical process industry,
various types of fluids are being used in different forms
like liquid, gaseous, slurry, etc. Raw material, intermediate
product or finished product produced through various
unit operations require connectivity of all the units with
pipelines and fittings due to the following reasons:
 Ease of operation
 Safe handling of materials
 Avoiding loss of material
 Hygienic conditions of the plant

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Materials Usedin Water Supply Pipes

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Materials Used in Water Supply Pipes
The pipes used to transport potable drinking water in a home plumbing system
use different materials than those used for the pipes carrying drain water. Your
home may have a plumbing system that uses all one type of material for the
water supply pipes, but don't be surprised to find several types of pipes,
especially in older homes that have seen many repairs or updates.

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Here are some common materials used for water
supply pipes.
Galvanized pipe is steel pipe that has been treated with a zinc coating. This
galvanized coating keeps the water from corroding the pipe. It was once the
most common type of pipe for water supply lines, but because labor and
time that goes into cutting, threading, and installing galvanized pipe, it no
longer used much, except for limited use in repairs. However, galvanized pipe
for water distribution is still seen in larger commercial applications.

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Copper pipe is mostly used for hot and cold water distribution, as well as being regularly
used in HVAC systems for refrigerant lines. Although once used in gas piping, this is no
longer allowed in most jurisdictions. Copper piping works in both underground and above-
ground applications, but copper can be affected by some soils and it should have a
protective sleeve if used underground.
PVC is an acronym that stands for polyvinyl chloride. Of the different types of plastic pipe
used for water supply, PVC has a wide variety of plumbing uses, from drainage pipe to water
mains. It is most commonly used for irrigation piping, home, and building supply piping. PVC
is also very common in pool and spa systems. PVC pipe is often white but it can also come in
other colors. You can often tell what it is used for by the colors and marks on the pipe. For
example, purple pipe with black lettering is used for reclaimed water. PVC also comes in a
variety of thicknesses, called schedules. Schedules 40 is the most common for pipes used in
water distribution.

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Galvanized pipe Copper pipe PVC pipe

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Water supply and sanitation in India

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Water supply and sanitation in India
The water supply and sanitation in India has improved drastically since 1980s. While
entire population of India has access to toilets, however, many people lack access to
clean water and sewage infrastructure. Various government programs at national, state,
and community level have brought rapid improvements in sanitation and the drinking
water supply. Some of these programs are ongoing.
In 1980 rural sanitation coverage was estimated at 1% and it reached 95% in 2018.The
share of Indians with access to improved sources of water has increased significantly
from 72% in 1990 to 88% in 2008. At the same time, local government institutions
mandated to provide drinking water and sanitation services are seen as weak and lack
the financial resources to carry out their functions. In addition, only two Indian cities
have continuous water supply and according to an estimate from 2018 about 8% of
Indians still lack access to improved sanitation facilities.

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Water supply and water resources
Depleting ground water table and deteriorating ground water quality are threatening the
sustainability of both urban and rural water supply in many parts of India. The supply of cities
that depend on surface water is threatened by pollution, increasing water scarcity and
conflicts among users. For example, Bangalore depends to a large extent on water pumped
since 1974 from the Kaveri river, whose waters are disputed between the states of Karnataka
and Tamil Nadu. As in other Indian cities, the response to water scarcity is to transfer more
water over large distances at high costs. In the case of Bangalore, the ₹33.84
billion (US$449.4 million) Kaveri Stage IV project, Phase II, includes the supply of
500,000 cubic meter of water per day over a distance of 100 km, thus increasing the city's
supply by two-thirds.[39][40]
In some coastal areas seawater desalination is becoming an important source of drinking
water supply. For example, the Chennai Metropolitan Water Supply and Sewerage Board has
put into service a first large seawater desalination plant with a capacity of 100,000 m3 per
day at Minjur in 2010. A contract for a second plant with the same capacity at Nemmeli was
awarded in the same year.

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Drain systems

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Drain systems
Introduction
Drainage is the method of removing surface or sub-surface water from a given area.
Drainage systems include all of the piping within a private or public property that
conveys sewage, rainwater, and other liquid waste to a point of disposal. The main
objective of a drainage system is to collect and remove waste matter systematically to
maintain healthy conditions in a building. Drainage systems are designed to dispose of
wastewater as quickly as possible and should prevent gases from sewers and septic
tanks from entering residential areas.

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Residential drainage systems
Residential drainage systems remove excess water from residential areas.
This system helps whisk water away from walkways, driveways, and roofs
to avoid flooding. Residential drainage systems are very important as they
prevent rotting, mold, mildew, and structural damage in buildings from a
buildup of water.
The types of residential drainage systems are:
1)Surface
2)Subsurface
3)Slope
4)Downspout/gutters

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Surface Drainage Systems
Surface drainage systems contain shallow ditches dug in a parallel pattern, which act as
canals for run-off water. Theses ditches lead the water into the main drain to avoid water
pooling and flooding.
Subsurface Drainage Systems
A subsurface drainage system is also known as a French drain. Subsurface drains are placed
beneath the top layer of soil to remove excess water at the root level. Subsurface drains
require the digging of deep ditches and the installation of underground pipes. A large
collector drain is installed to collect water from the pipes.

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Slope Drainage Systems
Slope drains allow water to flow downward from a structure with
the aid of pipes moving down a slope. A pipe is installed and
anchored into a small incline, which causes water to flow through
the pipe and away from the structure.
Downspout and Gutter systems
Downspouts collect water from gutters and divert it to the ground. A
downspout is typically connected to a gutter system on a building
and carries water away from the roof down to the ground.
Downspouts empty out the water on a slope so that the water does
not pool at the base of the downspout.

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Combined drainage
Combined drainage system implies the system of horizontal drains (open or closed)
with vertical wells. The purpose of vertical wells is to capture (drawn out) water-
bearing horizon and relieve the pressure head in the lower aquiferous stratum,
which allows considerably increasing the space between the drains. At that, the
wells at the outlet section are connected with the drains at the water elevation
level in them.
Combined drainage system is used in the cases when vertical or horizontal drainage
cannot provide required capture of groundwater. This type of drainage is used both
in homogeneous and stratified soils of different permeability and large thickness of
filtering stratum. Structurally, the horizontal drain of combined drainage system is
similar to the drain of horizontal drainage system, and drain holes are similar to
drainage wells of vertical drainage.

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Drain System

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Thank You