water supply system project2 (PDF)

WORLD HEALTH ORGANIZATION
MONOGRAPH SERIES

No. 42

I

WATER SUPPLY
FOR RURAL AREAS AND SMALL COMMUNITIES

WATER SUI 'PLY
FOR RURAL AR EAS AND
SMALL COMMT JNITIES
tIf1

EDMUNDG. WAGE
111

Chief Engineer and Associate Chief 4 f Field Party,
Division of Health and Sani ztion,
Institute of Inter-American / fairs,
Rio de Janeiro, Brazil

Sanitary Engineer,
Division of Environmental Sar tation,
World Health Organization, Genevh Switzerland

WORLD HEALTH ORGA 'IZATION
PALAIS DES NATIONS

GENEVA

Authors alone are responsible for views expressed in the Monograph Series of the
World Health Organization.
The mention of specific companies or of certain manufacturers' products does not
imply that they are endorsed or recommended by the World Health Organization in
preference to others of a similar nature which are not mentioned. Proprietary names are
distinguished by initial capital letters.
PRINTED IN SWITZERLAND

CONTENTS

I
I

Page

I

I
I

. . . . . . . . . . . .

.

-\

. . . . . . . .

9

Chapter 1. Basic considerations. . . . .( . . . . . . . .

13

I
Chapter 2. Planning. . . . . . . . . . . . . . . . . . .

26

Introduction.

~

1

Chapter 3. Ground water . . . . . . . . . . . . . . .

Ii

57

Chapter 4. Pumps . . . . . . . . . . . . . . . . .

121

Chapter 5. Surface water . . . . . . . . . . . . . . .

161

. . . . . . .
Chapter 7. Distribution and use . . . . \ . . . . . . . .

171

-

Chapter 6. Treatment under rural conditions

,

194

Chapter 8. Importance of management . I . . . . . . . .

227

. . . . . .
Chapter 10. Administration and finance . . . . . .
Chapter 11. Operation and maintenance . 1 . . . . .
I
Chapter 12. Long-term planning . . . . . . . . .

. . .

232

. . .

236

. . .

243

. . .

248

Chapter 9. Personnel and training .

WATER SUPPLY FOR RURAL AREAS

ANNEXES

Page

Annex 1. List of reviewers

. . . . . . . . . . . . . . . . . . . .

Annex 2. Conversion factors

. . . . . . . . . . . . . . . . . . . .

Annex 3. Flow measurements

. . . . . . . . . . . . . . . . . . . .

Annex 4 . Collection of water samples

. . . . . . . . . . . . . . . .

Annex 5. Construction of hand-dug wells

. . . . . . . . . . . .

Annex 6. Typical specifications for a hand pump
Annex 7. Construction of small dams

. . . . . . . . . . .

. . . . . . . . . . . . . .
I

Annex 8. Financial statements for small water-works

. . . . . . . . .

Annex 9. Some practical hints on the operation and maintenance of small
water-supply systems in rural areas . . . . . . . . . . . . . . . .

Select bibliography . . . . . . . . . . . . . . . . . . . . . . . 331

Index . . . . . . . . . . . . . . . . . . . .

:

..........

335

FIGURES

Page

14
The five principal causes of death in certain countkies of the Americas. 1952
Simple water-prospecting equipment . . . . . . . . . . . . . . . . . 37-38
52
A portable water-laboratory field kit . . . . . . . . . . . . . . . . .
Geological formations . . . . . . . . . . . . . . . . . . . . . . . .
58
Occurrence and distribut~onof sub-surface water . . . . . . . . . . . .
59
60
Comparison of free and confined ground-water . . . . . . . . . . . .
61
Shallow well in free-water zone . . . . . . . . . . . . . . . . . . . .
Well tapping confined water . . . . . . . . . . . . . . . . . . . . .
62
65
Types of bailers and buckets used for removal of material from holes . . .
Hydraulic methods of exploration . . . . . . . . . . . . . . . . . .
66
. . . . . . . .
Drilling and boring methods of exploration . . . .
69
Section of well shaft : first lift . . . . . . . . . . . . . . . . . . .
73
Dug well with protective casing and platform . . . . . . . . . . . . .
77
78
Dug well lined with concrete or clay tile . . . . . . . . . . . . . . . .
Reconstructed dug well with buried slab . . . . . . . . . . . . . . .
79
Dug well : casing descending with excavation . . . . . . . . . . . . .
80
Amazon well . . . . . . . . . . . . . . . . . . . . . . . . . . . .
81
82
Amazon well : grate beams . . . . . . . . . . . . . . . . . . .
Large well with horizontal perforated pipes . . . . . . . . . . . . .
84
85
Driven well with drop pipe and cylinder and protective platform . . . . .
Typical well points . . . . . . . . . . . . . . . . . . . . . . . . .
86
Well-point system . . . . . . . . . . . . . . . . . . . . . . . .
87
Tube-well boring by water-jet system . . . . . . . . . . . . . . . . .
91
Jetting a large-diameter casing (I) . . . . . . . . . . . . . . . . . . .
94
Jetting a large-diameter casing (11) . . . . . . . . . . . . . . . . .
95
Typical boring tools . . . . . . . .
. . . . . . . . . . . . . .
98

Properly protected spring (I)

. . . . . . .

. . . . . . .

. . . . . . . . . .

113

. . . . . . . . . . .

125

WATER SUPPLY FOR RURAL AREAS

Page
A sanitary rope-and-bucket well (11) . . . . . . . . . . . . . . . . .
133
Continous-belt bucket pump . . . . . . . . . . . . . . . . . . . . . 134
Multicellular band pump . . . . . . . . . . . . . . . . . . . . . .
134
135
Centrifugal pumps : turbine-type (I) and volute-type (11) . . . . . . . . .
Centrifugal pumps : directly connected to power unit (I) and with belt-drive (11) 136
Jetpump . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
137
Typical installation of jet pump . . . . . . . . . . . . . . . . . . .
137
138
Section of typical deep-well turbine pump . . . . . . . . . . . . . . .
Typical characteristics of deep-well turbine pumps . . . . . . . . . . 142-143
Effects of vanes and size of intakes on performance curve and capacity of
centrifugal pumps . . . . . . . . . . . . . . . . . . . . . . . .
Two pumping situations. showing centrifugal pump capacity curves . . . .
Deep-well turbine pump : electric motor (I) and direct drive and angle-gear
head (11)
. . . . . . . . . . . . . . . . . . . . . . . . . . .
Deep-well turbine pump : direct belt drive (1) and belt drive and angle-gear
head (TI) . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main parts of air-lift pump . . . . . . . . . . . . . . . . . . . . .
Hydraulic ram . . . . . . . . . . . . . . . . . . . . . . . . . . .
Windmill . . . . . . . . . . . . . . . . . . . . . . . . . . .
Properly designed hand or windmill pump with cylinder above ground . . .
157
Typical arrangement of windmill tower. pump. and well . . . . . . . . .
Typical pump installation using standard tee and underground arrangement
159
to discharge water below frost line . . . . . . . . . . . . . . . . . .
164
Cistern with sand filter (pump installation optional) . . . . . . . . . . .
Small intake structure . . . . . . . . . . . . . . . . . . . . . . . .
167
Profile of pipeline from source to distribution system . . . . . . . . . .
169
Filtered water outlet . . . . . . . . . . . . . . . . . . . . . . . .
177
Equipment for feeding hypochlorite solution . . . . . . . . . . . . . .
182
Apparatus for hypochlorination . . . . . . . . . . . . . . . . . . .
183
Berkefeld filter . . . . . . . . . . . . . . . . . . . . . . . . . . .
191
Typical zeolite water.softener. manually operated . . . . . . . . . . . .
193
Distribution reservoirs : theoretical reservoir capacity required . . . . . .
197
Ground-level reservoirs . . . . . . . . . . . . . . . . . . . . . . .
200
Elevated storage tanks . . . . . . . . . . . . . . . . . . . . . . .
203
Water-level indicator for elevated storage tanks . . . . . . . . . . . . .
204
Systems of distribution . . . . . . . . . . . . . . . . . . . . . . . .
208
Topographical plan of village and surrounding area . . . . . . . . . . .
General plan of distribution system . . . . . . . . . . . . . . . . . .
Possible arrangement of public fountain . . . . . . . . . . . . . . . .
Pressure tank system . . . . . . . . . . . . . . . . . . . . . . . .
Plumbing rods . . . . . . . . . . . . . . . . . . . . . . . . . . .
Locally made equipment . . . . . . . . . . . . . . . . . . . . . . .
Caissons and lining shutters . . . . . . . . . . . . . . . . . . . . .
Sinking headframe (type " G "). North Region. Nigeria : general arrangement
Small earth dam . . . . . . . . . . . . . . . . . . . . . . . . . .

Introduction

It is difficult to establish the exact degree of the importance of water
to man in his arduous climb up the ladder of civilization. It is certain,
however, that without water there would be no life of any kind on the earth
and that, without water readily available in adequate quantity and free o j
pathogenic organisms, man's progress is tremendously hindered. Although no
actual count is possible, billions of man-days of labour are undoubtedly
lost annually because of illness and death from water-borne diseases. Unfortunately, the areas which can least afford this economic loss are the places
where such sickness and death are most rampant.
The responsibility for reducing this tremendous waste falls on governments
and, specijically, on health administrations. It is the aim of this monograph
to assist the government officials who must meet this challenge. Among
those most directly concerned are public health administrators, medical
oj3cers of health, civil or sanitarj~engineers engaged in public health, and
sanitarians.
In an article discussing long-range planning for water service in the USA,
Dr Abel Wolman of the Johns Hopkins University, Baltimore, has said:
" Adequate water service, at a reasonable price, is an attainable objective.
I f it has not yet been attained, it is only because the skilled workers in this
jield have not seenjit to dejne the objective, to delineate the principles which
should control its implementation, to devise the structure for administration
and management, and to establish the fiscal principles which might safely and
wisely provide the sinews for the project."46 It has been the aim of'the authors
of the present monograph to cohsider these elements in particular relation to the
establishment of services for rural areas and small communities. An effort
has been made to discuss the problems of rural water-supply in a clear and
realistic manner and to avoid nebulous concepts which cannot possibly apply
to most of the rural underdeveloped areas of the world at the present time.
On the other hand, the authors have tried to show the minimum facilities that
are necessary in small communities and individual households in order to
satisfy the basic personal andpublic health objectives of water-supply schemes.
Perhaps the most important single step in a water-supply programme
is to get it started: in countries where it has been possible to get a programme
under way it has invariably prospered and expanded, and the result has
usually been the establishment of formal government agencies to handle