[PDF]Drinking Water Installations and Drainage Requirements in Nepal

MICROFICHE




A project of Volunteers in Asia



Residential and Non-Resi dential Drinking Water
Installations and Drainage Requireme nts in Nepai

By: Andreas Bachmann & Heinz Waldvogei



Published by: The Mechanical Training Centre (MTC)



Balaju

Kathmandu

Nepal

Swiss Center for Appropriate Technology (SKAT)

St. Gallon

SWITZERLAND



Available from: SKAT



Varnbuelstrasse 14
CH-900 St. Gallon
SWITZERLAND



Reproduced with permission.



Reproduction of this microfiche document in any form is subject to the same
restrictions as those of the original document.




== Residential and Non - Residential
l^i^g DRINKING WATER INSTALLATIONS
IjjjlJj AND DRAINAGE REQUIREMENTS IN NEPAL




The Mechanical Training Centre (MTC) is a vocational training centre run jointly
by His Majesty's Government of Nepal and the Government of Switzerland through
the Directorate for Technical and Vocational Education (Nepal) and Helvetas Nepal.



SKAT, Swiss Center. for Appropriate Technology, is a documentation centre and
consultancy group which is engaged in promoting Appropriate Technology in the
Third World. Its mail-order bookshop with more than 1200 publications in stock
and its publishing help to fulfill this aim.



First Edition
Second Edition
Third Edition
Fourth edition

Authors
Editor

Publishers

Copyright

Comments
Distributors



ISBN



1976

1979, expanded content
1982, slightly revised

1988, revised and expanded, co-published
by MTC and SKAT

Andreas Bachmann & Heinz Waldvogel

MTC (Mechanical Training Centre, Balaju,
Kathmandu/Nepal)

MTC, Balaju, Kathmandu/Nepal
SKAT, St. Gallen/Switzerland

Material of this publication may be freely
quoted, translated or otherwise used.
Acknowledgement is requested.

Questions and comments are welcome at MTC

in Nepal:

Mechanical Training Centre
P.O. Box 4897
Kathmandu / Nepal

outside Nepal:

SKAT, Varnbuelstrasse 14

CH- 9000 St. Gallen/Switzerland

and

KODIS, Wartstrasse 6

CH- 8400 Winterthur/Switzerland

3 908001 129



Printed in Nepal at SAHAYOGI PRESS, Tripureshwar, Kathmandu



The Mechanical Training Centre (MTC) is a vocational training centre run jointly
by His Majesty's Government of Nepal and the Government of Switzerland through
the Directorate for Technical and Vocational Education (Nepal) and Helvetas Nepal.



SKAT, Swiss Center. for Appropriate Technology, is a documentation centre and
consultancy group which is engaged in promoting Appropriate Technology in the
Third World. Its mail-order bookshop with more than 1200 publications in stock
and its publishing help to fulfill this aim.



First Edition
Second Edition
Third Edition
Fourth edition

Authors
Editor

Publishers

Copyright

Comments
Distributors



ISBN



1976

1 979, expanded content
1982, slightly revised

1988, revised and expanded, co-published
by MTC and SKAT

Andreas Bachmann & Heinz Waldvogel

MTC (Mechanical Training Centre, Balaju,
Kathmandu/Nepal)

MTC, Balaju, Kathmandu/Nepal
SKAT, St. Gallen/Switzerland

Material of this publication may be freely
quoted, translated or otherwise used.
Acknowledgement is requested.

Questions and comments are welcome at MTC

in Nepal:

Mechanical Training Centre
P.O. Box 4897
Kathmandu / Nepal

outside Nepal:

SKAT, Varnbuelstrasse 14

CH- 9000 St. Gallen/Switzerland

and

KODIS, Wartstrasse 6

CH- 8400 Winterthur/Switzerland

3 908001 12 9



Printed in Nepal at SAHAYOGI PRESS, Tripureshwar, Kathmandu



INTRODUCTION



Urbanization is profoundly changing the face of many nations. Rapidly growing cities
bring new possibilities, but also new challenges. One of the most vital of these challenges
is the provision of piped water and of efficient sanitation for an ever-growing urban population.

In Nepal, as in many other countries, sanitary installation represents a new trade. It was
with the intention of giving useful hints and guidelines to the practitioners of this trade that
the first edition of this book was published.

This fourth edition is the result of a steady demand for the book in many countries. The
opportunity has been taken to review and improve the entire text. Drawings have been redone
and the section on drainage has been considerably enlarged. As in earlier editions, more
than one solution is given for certain problems because some norms differ from country to
country. In all cases, however, care was taken to use standard terminology.

In preparation of this edition, special thanks are due to Mr. Laxmi Bahadur Manandhar,
Principal of M.T.C. and Mr. A. Wiederkehr of Helvetas, Zurich. Thanks are also due to Mr.
Ram Prasad Shah, Draftman; Mr. Ram Kumar Thapa, Office Asst.; Mr. Purna Man Shrestha,
Office Incharge. Grateful acknowledgement is owed to SSIV (Schweiz. Spenglermeister und
Installateur Verband) for much additional information on soil and waste water drainage. The
English language was checked and corrected by Mr. Nick Gregory.

This book is intended to be used as manual and reference work by practising sanitary
engineers. We hope that it will continue to be a valuable and trusted companion to many
planners and practitioners in Nepal and abroad.

Ben Dolf / Programme Director
Helvetas Nepal

Patrick Leu / Co-Principal
MTC, Balaju



FOREWORD



These guidelines were prepared in accordance with international and regional standards.
Much attention was also given to the local conditions to ensure acceptable and troublefree
installations.

This is the fourth edition, and has a wider coverage on drainage requirements in buildings.
In this we have tried to give a proper blend of different types of modern installation
technologies, suitable for actual needs. The manual includes essential details of technologies
of different countries. Expressions vary from one region and language to another and this
book aims to use internationally acceptable expressions without creating new words or
definations.

As the Mechanical Training Center has a Sanitary Section, updated schooling materials were
required. These guidelines were collected to give essential knowledge on sanitary installations
in buildings in Nepal. Although the guidelines are qu.te complete they are not intended for
self-teaching. This manual cannot and shall not be used in place of methodologically introduced
teaching materials nor should it be used in place of school lessons.

We are grateful to the concerned authorities in Nepal and to Helvetas for having supported
this new edition. Thanks also to Mr. R.P. Shah, Draftsman at MTC, for his many drawings
included in this book.



Andreas Bachmann & Heinz Waldvogel



Residential and Non - Residential

DRINKING WATER INSTALLATIONS
AND DRAINAGE KIQUIREMENTS IN NEPAL



PART 1

DRINKING WATER INSTALLATIONS



DRINKING WATER INSTALLATIONS



page

1 OBJECTIVES 1

2 FIELD OF APPLICATIONS 1

3 TERMS AND DEFINITIONS 1

4 PRINCIPLES OF INSTALLATIONS 2

5 PARTS OF PIPELINES 4

6 WATER METER 5

7 STORAGE TANKS 6

8 PROTECTION AGAINST CORROSION 9

9 MATERIALS AND CONNECTIONS OF PIPELINES 9

10 POSITIONING OF PIPELINES 11

1 1 INSTALLATIONS IN BUILDINGS 1 2

1 2 APPARATUS AND VALVES 1 7

13 FIRE HYDRANT LINES 18

14 FREEZING PROTECTION 18

15 DIMENSIONING 19

16 TESTING OF A NEW INSTALLATION 21



1



1.



OBJECTIVES



This manual explains how to supply and distribute pure water, free of impurities
and in sufficient quantity to the consumers. All connections to the main pipelines
must be technically sound, so that the water will remain uncontaminated.



This manual deals with drinking water installations from the town main supply to the
tapping places, including the connected apparatus, as follows:

- communication and service pipes

- domestic installations (house installations)

- cold and hot water supply

2.100 REQUIREMENTS

Installations between the distribution pipes and the water consumer must fulfill the
following requirements in order to maintain a pure and high quality water supply.

2.110 Hygienic requirements - The water must stay free of pollution or anything else harmful
to health. Examples:

- Absorbing dirty substances,

- re-infections (through bad or wrong installation)

Also to be avoided are:

- the heating of water from the pipes (sun, fire, etc.)

- noise transfers.

2.120 Technical requirements - The installation and all connected apparatus must be
adapted to the existing mains and flow pressure (from the distribution pipes) to
guarantee an adequate quantity of water.



3.101 Main - means a pipe laid by the water authority for the purpose of giving a general
supply of water but does not include a communication or service pipe.

3.102 Communication pipe - means that part of a service pipe which lies between the
main and the boundary of the street in which the main is laid.

3.103 Consumer - means a person supplied with water by the water authority.

3.104 Meter - includes an appliance or device used to measure or ascertain amounts of
water taken or used from the water authority's waterworks.

3.105 Service pipe - means any portion of any pipe or any fittings from the water authority's
mains to any premises which conveys or is capable of conveying water under pressure.

3.106 Supply pipe - means any portion of any pipe which is not a communication pipe.

3.107 Storage tank - means any tank for containing water supplied by the water authority
or by the consumer, other than a flushing tank or hot water tank.

3.108 Flushing tank- means a tank with a discharging apparatus for flushing a water closet,
sink, urinal or drain.



2.



FIELD OF APPLICATION



3.



TERMS AND DEFINITIONS



2

3.1 09 Cylinder- means a cylindrical closed vessel capable of holding water under pressure.

3.110 Water fittings- includes pipes and parts to change direction, branches, etc., (other
than mains) taps, cocks, valves, etc.

3.111 Apparatus- includes water closets, wash basins, bath tubs, kitchen sinks, machines,
tanks and other similar devices. Usually they have a drain for connection to the
waste water system.

3.112 Stop cock - includes stop tap, stop valve, angle valve and any other device for
stopping the flow of water in a line of pipes.

3. 1 1 3 Ball cock - means flow operated valve for controlling the inflow of water to a tank.

3.1 14 Overflow pipe - means a pipe so fixed that the discharge of water may readily be seen.

3.115 Waterworks- includes all . catchment areas, reservoirs, wells, boreholes, dams, weirs,
tanks, cisterns, tunnels, filter beds, conduits, aqueducts, fountains, standposts, sluices,
valves, hydrants, pumps, prime movers and all other structures or appliances used
or constructed for the collection, storage, conveyance, supply, measurement or
regulation of water, and which have been constructed by or on behalf of the water
authority and are the property thereof or which shall hereafter be used or constructed
by the water suthority.

3.116 Premises - includes dwellings, buildings, lands and leasements whether open or
enclosed, and whether public or private.

3.117 Catchment area - means any surface of land or other area which collects rainfall
for the purpose of the waterworks.



4. PRINCIPLES OF INSTALLATIONS

4.100 FUNDAMENTAL RULES

4.101 Continuous supply from the mains - the water authority will endeavour to maintain
continous supply of potable water to consumers but will not be liable for compensation
in respect of loss or damage caused by or attributable to any failure or disruption
or supply.

4.102 Security - The quality of the water supplied must remain uncontaminated. And the
installations made by the plumber must be carried out with greatest care, according
to this manual.

4.103 Skill and supervision - Practical work should be done only by specially trained
persons. To attain this manual's standard, the installation should be supervised
during construction and in operating conditions.

4.104 Materials - all materials installed should be of good quality to guarantee proper,
trouble-free function and long life for the installation.

4.105 Apparatus - The sanitary apparatus supplied must be of standard make and connected
with the septic or sewer systems. Protection against the exit of the poisonous and
bad smelling gases must be ensured by means of siphon or trap.

4.1 vJ6 Existing installations - Should also conform to the rules of this manual. If safety is
not guaranteed, repairs should be done immediately.

4 200 PROTECTION FROM DAMAGE FROM FROST

Every water fitting, whether inside or outside a building, should be placed so as to



3



reduce the risk of damage by frost.

4.300 SUPPORT OF PIPES

Every pipe shall be properly supported and so arranged as to avoid air locks or
reverberation.

4.400 PROTECTION AGAINST WATER HAMMER

Both in choice of apparatus and design of the installation, consideration should be
given to the avoidance of water hammer.

4.410 Plug valves - should not be used, except for draining purposes.

4.420 Spring loaded flushing systems - (as for closets, urinals) should be avoided, instead
cisterns should be utilized. If a spring loaded flushing system is necessary then it
should be installed so that there is no possibility of a cross connection between the
drinking water and the waste water system.

4.500 PROTECTION FROM DAMAGE FROM OTHER CAUSES

Every water fitting should be so placed as to be readily accessible for purposes
of examination and repair.

4.510 Dissimilar metals - water fittings of unlike metals should not be used unless effective
measures are taken to prevent deterioration.

4.600 DIRECT CONNECTION OF TOWN SUPPLY

With pipes from private water supplies is not allowed.
4 700 PREVENTION OF WATER POLLUTION

4.710 Principles

4.720 The entire installation has to be assembled so that there is no possibility of back
siphonage or back-flow of foul water or sewage or any form of pollution to the
installed water system.

4.730 Pipes are not to be laid through sewers, - etc: No pipe shall pass into or through
any ashpit, manure pit, sewer drain, cesspool, trash chute or through any manhole.

4.740 Cross connections - from the drinking water with the waste water system are prohibited.

4.750 Waterworks have to be kept clean. It is not permissible to deposit any earth, material,
liquid or any dead creature in such manner or place that it may be washed, fall
or be carried into the waterworks. However, nothing in this section shall be analysed
as prohibiting or restricting:

a) any method of cultivation of land which is in accordance with the principle of
good husbandry; or

b) the reasonable use of oil or tar on any highway maintainable at the public
expense, so long as all reasonable steps are taken lev preventing the pollution
of any part or any water of the waterworks.

4 800 APPROVED MANUFACTURE

All pipes and fittings which carry water supplied by the water authority must comply
with their regulations and be of approved manufacture.



4

4.810
4.820



4.900



4.910



5.

5.100



Costs of replacement - All water installations have to be of good quality. It is required
that water is kept clean and is not contaminated in any way, also including through
defective installation. Consumption has to be within reasonable limits and must be
measured properly. Although water is supplied by the water authority, alteration or
renewal of pipelines and fittings may be charged to the consumer.

Entry into premises - The water authority may enter into premises into which pipes
have been laid for the supply of water:

a) to inspect any supply pipe

b) to regulate and repair any supply pipe or meter as circumstances may require

c) to ascertain consumption

d) to disconnect the supply pipe to any premises or to suspend, stop, turn off or
divert the supply of water to any premises or to suspend, stop, turn off or divert
the supply of water to any premises.

DISTRIBUTION OF WATER FROM OTHER SOURCES

The concerned person should apply to the water authority for a licence if the water
has to be supplied from under ground or from a river, lake or pond lying within
the distribution area of the water authority.

However, a license may not be required for the under mentioned conditions which
should be checked for approval with the concerned water authority:

a) If somebody wishes to take water supply of up to 5,000 liters (or the proper
quantity approved by the water authority) for household purposes.

b) If some land owner wishes to take the water supply for cultivation of his own
land from the nearest source attached to his land.

Responsibilities of waterworks - Waterworks are under the responsibility of the water
authority for the following:

a) operation of waterworks

b) maintain the quality of water supply

c) grant permission to draw off, divert or take water from any stream or waters
by which the waterworks are supplied, or

d) arrange to open or shut any valve, hydrant or stopcock belonging to the water
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