W ATER SUPPLY SYSTEMS

Interior Services -I
 W HAT IS WATER SUPPLY ?
Water supply is a provision to deliver water to consumer with
appropriate quality, quantity and pressure by public utilities,
commercials organizations, community endeavors, usually via
system of pumps and pipe.

WATER SUPPLY SYSTEM , Infrastructure for the

collection, transmission, treatment, storage, and distribution
of water for homes, commercial establishments, industry,
and irrigation, as well as for such public needs as firefighting
and street flushing. Of all municipal services, provision of potable
water is perhaps the most vital. People depend on water for
drinking, cooking, washing, carrying away wastes, and other
domestic needs. Water supply systems must also meet requirements
for public, commercial, and industrial activities. In all cases, the
water must fulfill both quality and quantity requirements.

INTERIOR DESIGN
INTERIOR SERVICES -I 3rd SEM
 M ETHODS OF W ATER SUPPLY
Water supply from the mains to the building is through one of the following
system depending on the pressure of the water and timings of the supply.

Direct Supply System (upward distribution) :

•Supply of water is directly given to various floors with required pressure

for sufficient hours.
• This is only useful for the building which is not more than two floors.
•Separate connections to be provided for domestic and non-domestic
requirements.

Indirect Supply system (down take supply) :

• Used generally when the pressure in the mains is not sufficient.

• The water is pumped directly to the overhead storage tank and from
there the water is supplied to different floors by gravity.
• The water stored in the underground tank and from the water is pumped
to the overhead tank and then it is supplied to different floors by gravity.

INTERIOR DESIGN
INTERIOR SERVICES -I 3rd SEM
 INTERIOR DESIGN
INTERIOR SERVICES -I 3rd SEM
 W ATER DISTRIBUTION SYSTEMS
The purpose of distribution system is to deliver water to consumer with
appropriate quality, quantity and pressure. Distribution system is used to
describe collectively the facilities used to supply water from its source to the
point of usage.

INTERIOR DESIGN
INTERIOR SERVICES -I 3rd SEM
 REQUIREMENTS OF GOOD DISTRIBUTION SYSTEM

 Water quality should not get deteriorated in the distribution pipes.

It should be capable of supplying water at all the intended places with
sufficient pressure head.

It should be capable of supplying the requisite amount of water during

fire fighting.

The layout should be such that no consumer would be without water

supply, during the repair of any section of the system.

All the distribution pipes should be preferably laid one meter away or
above the sewer lines

It should be fairly water-tight as to keep losses due to leakage to the

minimum

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INTERIOR SERVICES -I 3rd SEM
 S ERVICE CONNECTIONS
A service connection is primarily a connection from the distribution system
to the consumer. A consumer may be a single house, an apartment house, a
planned block development or a water district buying water wholesale. A
domestic service connection involve following components:

1. Brass or Bronze ferrule - ferrule is the right angled sleeve made of

Brass or Bronze. For a typical service connection to a house, ferrule is
inserted in the main, most usually an “under pressure” connection which
can be inserted without shutting down the main.

2. Goose neck - This consist of 40 to 50 centimeter long curved piece of

flexible pipe made of brass, copper or lead. The goose neck prevents the
breaking of the main service pipe due to the movement that takes place
between the water main and the service pipe, thus providing flexibility of
the junction.

INTERIOR DESIGN
INTERIOR SERVICES -I 3rd SEM
 3. Stop cock or curb valve- It is installed in a suitable chamber with
cover, to close down the supply, for repairs of plumbing system.

4. Main service pipe - It may be of various materials. Its diameter may

vary from 12mm to 40mm

5. Water meter - It is also installed in a suitable chamber with cover. It

measures the quantity of water used by the consumer

INTERIOR DESIGN
INTERIOR SERVICES -I 3rd SEM
 INTERIOR DESIGN
INTERIOR SERVICES -I 3rd SEM
 ESTIMATION OF WATER REQUIREMENTS
For residential buildings, Indian standards recommends that a water
requirement of 135 liters per head may be assumed. Out of this, 90 litres
may be taken for domestic purposes while the balance 45 litres are taken
for flushing requirements. The requirements of water other than residence
are mentioned in the table below.

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INTERIOR SERVICES -I 3rd SEM
 D IFFERENT METHODS OF W ATER DISTRIBUTION
These are the methods employed for water
distribution in a building

1. Regular System
Water from UG tank is pumped into oh tank
and then distributed below in uniform
manner. A bigger diameter pipe is used on the
upper level and smaller diameter pipe on
lower level.

2. Divided OH Tank System

It is employed for multi storey buildings. The
oh tank is divided into several units, say in a
30 storey building, for every 10 storey section
an oh tank with separate pipe is provided.
The bigger diameter pipe is employed on
upper level and smaller diameter pipe on
lower sections. The division of overhead tank
allows uniform distribution of water and
saves power.
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 3. Hydro pneumatic System
Under this system, total requirement of water stored
in UG tank is supplied under a pressure. The
elimination of oh tank saves the cost of construction
and reduction in the cost of structure which bears
the load of oh tank. Structurally weak buildings
unable to bear the weight of oh tank or buildings
without a flat top also can use this system. The only
disadvantage of this system is that it required round
the clock supply of electricity.

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INTERIOR SERVICES -I 3rd SEM
 Size of Pipes Used
To carry water from UG tank to OH tank, galvanized iron (GI) pipe of 3.8 cm
diameter (diameter of such pies are measured internally), sometimes upto
5cm are employed.

Division of OH Tank
The OH tank is usually divided into two compartments for 1. Flushing 2/3
capacity and 2. Domestic 1/3 capacity. The use of water meant for WC’s,
urinals, comes under flushing, while domestic covers drinking water or water
from any outlet that has possibility of human consumption like tap for
drinking water, shower, wash basin, sink, etc.

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 Pipes sizes for fixtures Supplies
The table here gives the various sizes of pipes suitable for various uses

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INTERIOR SERVICES -I 3rd SEM
 M ATERIALS USED FOR SERVICE PIPES

1. Copper Tubing - Copper tubing is non-corrosive with most waters. It is

used extensively in better grade houses and where ground water is highly
corrosive to steel pipe. It has considerable strength, reasonable ductility,
and is obtainable in long lengths. Copper tube can be attached to the main
without the use of conventional goose neck, the flared end of the tubing
being connected directly to the corporation cock without threading.

2. G.I Pipes - These are used where water is suitable. In India, these are
extensively used because of their low cost. Galvanized iron or steel tubes
corrode more readily in soft and acid waters and are not so easily
manipulated as copper, although they are stronger and can be used in hard
water area where they withstand the hammering needed to remove the
scale.
.

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INTERIOR SERVICES -I 3rd SEM
 3. Lead pipe - Lead pipe has the following advantages (i) Highly resistant
to corrosion (ii) Highly flexible and (iii) High hydraulic co efficient of flow.
Lead has cumulative poisoning effect, specially when it goes into situation.
Due to this, it is not preferred.

4. Polyethylene Tube -These are being increasingly used internally and

externally for cold water service pipes only. Plastic pipe has following
advantages (i) It is lower in cost (ii) It is non corrosive (iii) It is light in
weight (iv) It can be installed with ordinary tools (v) It is more resistant to
bacterial scale and (vi) It has some insulating value. However these are not
useful where temperature is high.

INTERIOR DESIGN
INTERIOR SERVICES -I 3rd SEM