Water tanks with guttering and hand-pump

8/9/2019 Water tanks with guttering and hand-pump

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“Harvesting Rainwater i n Semi—arid Africa” consists of 6 Manuals:

Manual No. 1 . W a te r T a n ks w i t h G u t t e ri n g an d Hand—pump..

Manual No. 2 . Small Earth Da m b ui lt b y An i m al Traction.

Manual No. 3 . R o ck C a tc h m e nt Da m with self—closing Watertap.

Manual No. 4 . Shallow Wells with Bucketlift.

Manual No. 5 . Sub—surface an d Sand—storage Dams.

Manual No. 6 . Spring Protections.

Each Manual deals with siting criteria, standard d e s i g n s an d bills o fquantities i n a s i m p l e t ex t an d drawings.

Th e Manuals ar e based on practical experience gained by building700 water structures for rainwater harvesting i n semi—arid Kenyath e last 1 4 years.

Copyright

Permission i s hereby given for reproduction o f this material, i n wholeor part, for educational, scientific, o r development related purposes,except those i n v ol v i ng c o m m er c i al s a le o r services, provided t ha t f u ll

citation o f th e source i s given.

Reproduction for commercial purposes ma y not take place without prior

permission from:

ASAL Rainwater HarvestingP . 0 . Bo x 1 4 3 3 3

NAIROBI

Kenya —.

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A C K N O W L E D G M E N T

Th e authors o f these manuals are grateful f or t he grants

Danida w hi ch m ad e possible th e compiling a nd p ub li sh in g

e x p e ri e n ce w i t h rainwater harvesting for self—help groups i nareas o f Af r i c a.

given by

o f their

semi—arid

M uc h g ra ti tu de i s also du e to th e Ministry o f Agriculture i n Kenya,w h i ch t o ge t he r w i t h Danida afforded th e opportunity o f d e v el o p i ng l o w—technology an d labour-intensive methods o f harvesting rainwater an d

thereby enabling people an d livestock i n a semi—arid region o f th ecountry t o have access t o a steady water supply.

Thanks ar e also du e t o th e local inhabitants with a nd f or whom these

t ec hn i qu es w er e developed an d i m p le m e n t e d . Their understandable

skepticism i n starting u p t he se demanding activities gave th e process

a sound an d realistic foundation on which t o build.

Personal thanks ar e v er y m u ch due to:

P re be n E nh ar d o f Nutomo Soil an d Water Conservation Project for his

considerable support.

Ja n Nissen—Petersen for assisting i n drawing more t h an h alf o f th e

many drawings.

Ki m Nissen-Petersen f or t he many proof—readings an d useful comments.

Erik Nissen—Petersen and Mich ael Lee

( ii )





CONTENTS

P A G E

SURVEYORS MANUAL ON WATER TANKS 1

1 . Types o f tanks described. Standard designs 12 . Calculating th e u s er s w a t er needs 6

3 . Calculating volume o f run—of f s from roofs 74 . Calculating volume o f w a te r t a nk s 8

5 . Bills o f quantities 9

6 . Quality control an d maintenance 1 1

CONTRACTORS MANUAL ON WATER TANKS 1 3

CYLINDRICAL TANK, 2 1 c u bi c m e tr e volume 1 4

1 . Site preparation 1 42 . Building instructions 1 5

EXTENDED GROUND TANK, 7 8 cubic metre volume 2 0

1 . Site preparation 2 02 . Building instructions 2 13 . Quality control an d maintenance guidelines 2 94 . Cleaning an d management 3 0

CONTRACTORS MANUAL ON GUTTERS 3 1

1 . Manufacturing gutters 3 22 . Manufacturing V—shaped gutters 3 43 . Installing V—shaped gutters 3 84 . Manufacturing square gutters 4 05 . Installing square gutters 4 26 . Quality control and maintenance 4 4

CONTRACTORS MANUAL ON HAN D -PUMP 4 5

1 . Th e Hand—pump 4 62 . Materials f o r t he Hand—pump Manufacturing 4 73 . Manufacturing Instructions 4 84 . Installation o f Pump a t Extended ground Tank 5 2





S U R V E Y O R S M A N U A L

1 . T y p e of T an k s Described

O N

W A T E R T A N K S

This manual d e a l s w i t h tw o types o f water t an ks f or r oo f catchments:

a . A cylindrical tank with a volume o f 2 1 , 0 0 0 l i t re s ( 2 1 cu.m.) m ad e

o f ferro—cement and roofed with iron s he et s. W a te r i s d r aw n f r omth e t an k by gravity t o a water ta p placed a t th e f lo o r o f th e

tank.

This t an k i s most suited t o smaller public b ui l di n gs , l ar ge rprivate homes a nd f or storage tanks for spring protections.

Th e tank i s modified t o cu t construction c os ts t o h a lf t ha t o f aconventional t an k w i th a volume o f 2 1 ,000 litres. No t o n ly i sthis method cheaper t o build, a cylindrical ferrocement tank i salso stronger an d more durable than tanks m ad e o f bricks, blockso r galvanised iron.

Because o f th e raised extension an d th e r u n— o f f f r o m th e rooftop

th e quality o f th e water i s v er y h i gh w i th little s e d i m e n t an d

lo w levels of organic pollution.

I f th e t an k i s full a t th e start o f a si x m o n t h dr y season i twill provide 120 litres p er d ay f or t he length o f th e dr y period.

300 mm.roin s e u s o c i ~

~ThC O N S U M P T I O N2 1 .6 0 0 L i t res i~oIitr~pe r d a y180 days without ruin

1





Standard Design o f 2 1 cu.m. Tank

1 6 g G I wirelQcmapfll

Third coato f mor ta r (1 .3 )3cm thick

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Founda t ion of- “o o sconc re te (1 :3 :4 ) 0 .0 -

‘//// /Ç77///// /

2 . 1 0

2 .0 2

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Gotvan ized co r r uqo t ed r oo f i ng sheets

‘~‘-~~A~ ~fl~&fl P~R~r~.’~A%ttfl J!’ ~

Re in fo rced withB .R .C .w e ld & ch icken m esh

“1st coat , mor ta r (13) 3-S m m .thick“Second coat o f mortar (1:3)

3cm thick &acoatof ni t .f-

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GaLvanized co r r uqo te d r o o f ing shee ts

W 4”G I.waterp ipe

T17,-r [‘nid

~upip~gutters.

2





b . A hemi—spherical underground tank o f f erro—cement

extended above ground level with a cylindrical wallblocks or stone masonry and roofed with i r o n s h ee t s.volume o f th e tank i s 7 8 , 0 00 l i tr e s ( 78 cu.m.).

Water i s d r aw n f r om t he t an k b y either a h a n d — p u m p or buckets.

Because water ha s t o b e lifted out o f the ta nk b y hand, therew i l l o c c ur little wastage and the consumption level will b e l ow er

than i f water could flow freely from a tap. This type o f tank i st he re fo re w el l suited for schools where pupils might forget t oclose a water ta p or p l a y w i t h freely running w a t er f r o m a t ap .

Because o f th e raised extensiQn an d th e r un — of f f r om th e rooftop,

th e quality o f th e water i s v e ry h i gh w i th little sediment an d

lo w levels o f organic pollution.

I f th e tank i s full a t t he s t ar t o f a si x month d ry s ea so n i twill provide 4 5 9 litres pe r day with little loss t o evaporation.

- --

Av e rage annua l ra ins - ‘

811mm. ..- :Ç 66Utres~~Litre5

which i so f either

Th e total

3





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65cm high o f bricks or b locks

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Extens i on w~tlo f stones s e t in mortar(1Z ) r e in forced with 1 2 r o unds o f barbedwire 5.5cm apart and covered withm orta r.

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2. C A L C U L A T I N G T H E USERS W A T E R N E E D S

Calculating Detand

Calculating th e water needs o f th e user i s relatively easy an d

involves a simple formula w h i c h i n c l ud e s th e average daily consumptiono f w a te r f r om th e tank per person ( or livestock), th e number o f days

i n t he dr y season, and the numbers o f people using th e tank. Studiesh a ve s ho w n that people with tanks next t o t h ei r h ou se s w i ll o f te n us e

f r om 2 0 — 4 0 litres o f water pe r person pe r d ay . This i s high compared

to people who m u st w al k l on g d i s ta n ce s fo r water w ho m ay u se le ss t h an1 0 litres per family per day . As an average, assume that each personwill t ak e 2 0 litres per day i f i t i s a household tank, an d 5 litres

per day i f i t i s a school or health centre tank. Th e formula is ;

Demand (in litres) = No. Dr y Day s x No. Litres Taken x No. People

Fo r example, a household with six members wi ll n ee d th e following

amount of water fo r a 1 80 d ay d ry period.

Demand = 180 dr y x 2 0 litres x 6 people = 21,60 0 litres.

I n t hi s case a 2 1 c u bi c m e tr e raised t a n k w o u ld b e a l m os t p e r fe c t for

t he ir n e ed s. H ow ev er , i t m ig ht b e t ha t t hey could not afford a 21,0 0 0l i tr e t an k but only a cheaper 7000 litre tank. Th e same formula could

b e rearranged to s ho w t he m how m u ch w at e r s uc h a tank could supplyeach family member each day during the dry season.

A private contractor must b e able t o understand t he se i d e as o f demand

an d supply and b e a b le to calculate them. Th e tank o w ne r m u st clearly

understand how m u c h w a t er th e family can expect t o receive e a c h s e as o n

an d how that compares t o t he i r n e ed s .

Remember: i f th e consumption i s higher than estimated, the t an k wi ll

run dry before th e n e xt r a in y season.

6





3. C A L C U L A T I N G V O L U M E OF RUN-OFF F R O M ROOFS.

Two f a ct o rs m u s t b e known for calculating th e volume o f run—off from

roofs.

1 . Th e arep o t t he r oo f f r o m w h e re th e r un — of f w i ll b e collected.

T hi s f ac to r i s found b y multiplying th e length o f t h e r o of withi ts w i dt h.

Example:

length o f r oo f 1 2 . 85 m x width o f r oo f 7 . 65 m = 98.3 sg.m.

2 . Th e a nn ua l r ai nf al l f ro m a y e a r w i t h poor rainyusing such a lo w figure th e roof catchment system

s u f f ic i e n t w a t er during y e ar s w i th p o or rainfalls.o f calculating this figure i s t o deduct th e averagewith 50 %.

Example:

seasons. By

will supply

Th e best waya n n ua l f i g ur e

Average a n n ua l r a i n fa l l 6 20 m m x 5 0 = 3 10 m m annual poor rainfall100

Th e annual volume o f run—off during a y e ar w i th poor rainy seasons i sfound b y multiplying the roof area (sq.m.) with th e a nn ua l r ai n fa ll

( mm ) .

Example:

Roof area 98.3 sq. m. x rainfall 31 0 m m = 3 0 , 4 73 l i tr e s = ( 3 0 .5 c u. m .)

I t i s important t o b e f u l ly c o n v er s a nt w i t h th e calculating o f run—offfrom roofs, because b y knowing this volume o f water th e r i gh t s i ze o ftank ca n b e designed.

I f th e roof i s to o small f or t he size o f tank wanted, th e onlysolution i s t o extend th e roof, or t o expect a higher rainfall.

7





4. Calculating Voli~of Water Tanks.

a. The volI.Ine of a cylindrical tank is calculated according to following formula:2

p i x r x h = voltine. This means 22 x (radius x radius) x height = volume7

22x (radius 1 . 8 7 mx ra d iu s 1 . 87 in) x height 1.90 in = 20,881 litres7

LO W ER P A R T U P P E R P A R T

6 Q 62 5 i ~ 60 ,62 5 rr~

V o l u m e o f sphere:ii~. Vo l u m e o f cy l inder: nr2h

Vo l u me o f hern i -sphere: 22x3.07x3.07x0,60 1 ’~773h t res

2 2 614X 6 14X 6 14 60 ,625 l i t res. ~ 6 0 , 6 2 5 + 1 7 , 773 = 78,398 litre vo lume

Calculation of Storage V o l u m e .

b. The volume of ahemi-s~iericaltank is calculated accordingto two f o r i r i i ] a s :

1. The voltine of a hemi-s~er1ca1form is:3

p i x d = volume. This means 22 x (diametre x diametre x diametre) = volume2x6 7 2x6

Example: 22 x (diametre 6.14 m x diametre 6.14 in x diainetre 6.14) = 60,625 litres7 2x6

2. The volune of the cylindrical ~tensicxi is calculated as:2

p i x r x h = volume, which is 22 x (radius x radius) x height = volume7

Example: 22 x (radius 3.07 x radius 3.07) x height 0.60 = 17,773 litres7

Grai~c o l t in e of be~iis$~ericaltank 78 , 398 litre

8





Skilled labour for 12 days x

Cement, 1,250 tcunes

B.R.C. mesh No. 65 or 66 .

Chicken mesh, 1” x 3 ft. x 30 m

Biitçwfre

Draw-off stand pipe and tap

Thipty sugar sacks for supportiug

plastering

Sisal twine threed for sugar sacks

Transport of 3 tccnes x ... ke inclusive

Guttering not inclnded

= 5 h z

For ctnverting tames

1 tame o f cement =

ltctmeofsand =

ltcsmeofstcties =

ltcimeofwater =

into wxe understandable teru~following fonrula can be used:

20 bags of cement.8 w heel barrow s.8 w heel barrow s.5 d r ain s .

5 . B il l s o f Q u ant iti es

Cylinirica]. tank, 21,000 litres.

Bill of Quantity far itenE to be delivered1~the donor/Ministry.

2cœtractorsxShs =5hz

25bags xShs =5hz

iroll xShs =5hz

2rolls xShs =5hz

xShs =5hz

iset xShs =Shs

2Oixis xShs =5hz

2kg xShs =5hz

returntrip...xShs =5hz

Thtal Œst f o e project Sis

Bill of Quantity far iteiis to be delivered free of tharge by the self—help group.

Unzkilledlabourforl2daysx 4].abcurers ....xshz =5hz

Sand, clean and œarse 4 tc*mes = 32 wheelbarrows x 5hz = 5hz

Ballast, Sanstcsies 2tœnes=l6wheelbarrows xShz =5hz

Water 2tcsmez=lødruns xShz =Shs

Transportbycartsofl2tcnnes=24cartsx...]cm....xShs

‘Ibtal value of self-help 5hz

ndtotalœstandvalueof tank Sis

9





5. Bills o f Quantities

Extended grard tank, 78,000 litres

Bill o f Q u a n t i t y f o r item t o b e d el iv er ed b y t h e dcnr/Ninistry

= Sh s= Sh s= Sh s= Sh s= Sh s= Shs= Sh s= Sh s= Sh s= SI~s= Sh s= Su s= Sh s= Shs= Sh s= Shs

Gutteri.rç inclwiedThtal cxst for project &is

B il l o f Q u a l i t y f o r it~st o b e d el iv er ed f r ee o f t h a r g e b y t h e self—help group

IMskilled labour f o r 2 5 d ay s xS a n d , c l ea n a n d c o a r s e

S to nes , c l ea ne d W at erT r an s p o r t b y c ar ts o f 2 5 tames x 1 c m

4labcurers..xshs =Shs

l 4 t c c i n e s xShs =5hz

6tcmnes x5hs =Shs

4tc*mes xshs =5hzSocarts x & i s =5hz

Total v al ue o f self—help Shs

Grand total cost and value o f t a n k 8 h z

For converting tonnes into nxre understandable terms following f orniila can be used.

1 to nne o f cement1 tonne o f sand1 to nne o f stones1 tonne o f water

= 20 bags o f cement.= 8 wheelbarrows.= 8 wheelbarrows.= 5 d ru m s .

Skilledlabc*.irforlsdaysxCement 2 . 4 tonnes =

thicken mesh, 1” x 3 f t . x 3 0 m Barbed wire, gauge 1 6

Nails, 2 1/2”Thin polythene sheeting f o r c u r i n g

Galvanized pipe, 1 1/2” with flat irons~ 4 ” x ~

Corrugated roofing sheets, gauge 3 0 , 3 m

Nails f o r roofing, 4 ”Roofing nailsGutters, triangular, 2Oan overlap, g 2 6

Splash guards f o r gutters, 2Oan overlap g 2 6

Gutter hangers f o r triangular gutters, 3 n u -

Clot nails f o r fixing downpipesBitunen paste for sealing overlaps

2 contractors x Sh s48bags xShs3rolls xShs3rolls xShs

20kg x5hs3 0 metres .... x 5 h z

3.25 m etr es . x 5hz77metres xShsl5sheets xShs5kg xshs8kg xshs

S6metres xShsS0metres xshs

8Ooos xShs1kg xShs2kg xShs

Tra n spor t ofs t ca me s x kminclusivereturn....xShs =Shs

10





6 . Quality Control and Maintenance

I t i s o f great importance t ha t t he f i rs t , second an d fi nal co at o fplaster be completed w it hi n o ne d ay a nd t ha t t he p la st er m ix ratios

and reinf orc ement be th e same a s those listed i n th e building

instructions. I f th e proportion o f cement i n th e mix has been

r e d uc e d, e i th e r through a f al se attempt a t economy or through cheatingthen the wall wi ll be crumbly and f la ke a ft er wetting. I f th ereinforcement has b e en i m p r op e r ly made, large cracks will appear. I fth e curing h as n o t been carried ou t effectively and f or l on g e no ug h,

large n um b e r s o f small cracks will appear. Al l these faults ar e duet o i n co rr ec t f o ll ow in g of th e building instructions given. I f th e

instructions are followed closely t h en t he r e should b e no problems.

I f th e roofing o n t he t an k h as no t been constructed s o that t h ey d r a in

towards th e centre o f th e tank an d th e gap, then w a te r k i ll not fillt he t an k properly and may e v en f l o w outside o f th e tank.

I f th e gutters have not b e e n h u ng properly on th e roof edge s o that

they slope gradually down towards th e t a n k t h en th e water running of fthe roof will no t flow properly into th e tank. Instead i t ma y justbuild—up i n th e gutter and overf low onto t he g ro un d alongside th ehouse.

I f cracks d o appear in th e t a nk t he n depending on th e seriousness o f

th e cracking, several actions ca n b e taken.

I s th e lining of th e tank crumbling of f th e wall?

I f i t i s th e mortar needs t o be removed and th e lining b eg un a ga in

from th e beginning.

I s th e surface covered w i th s m a ll c rac ks but still solid?

I f i t i s then i t dried too quickly and a third coat o f plaster can be

applied with a second waterproof ing. Curing sh ould be done properly

this time.

Ar e there on e or tw o large cracks i n the tank through whichwater leaks out?

I f there ar e then these need t o be chiseled ou t an d th e leakage

blocked. Th e best method i s t o chisel away 3—6 cm either side o f th e

crack so that the barbed wire and chicken mesh i s exposed. Newstrands o f wire should be knitted into th e wire t o form a tighter mesha nd m or ta r s ho ul d be packed in once th e surface ha s been wetted an d

dusted with cem ent. A smooth an d complete coat o f plaster should be

applied over th e crack an d onto th e wall o f t he t a nk around the cra ck.Single small cracks ca n be painted with bitumen paste.

1 1





Does water collect in th e gutters bu t fail t o f lo w freely

towards th e tank?

I f this i s the case, the hangers need t o b e suspended a t an

increasingly lower level towards th e tank en d o f th e roof.

D o es w at er d r ai n a wa y f ro m th e opening i n t o th e t an k o n ce i tflows onto th e roof?

I f th e tank roofing does not d r a i n t ow a rd s th e centre o f th e tank i tn eed s to b e removed and repositioned s o t ha t i t does. T h i s s h ould not

happen i f th e correct height o f wall an d correct length o f galvanised

support p i p e ha s been used.

9 . 3 . 6 Maintaining an d I m p r o v i n g W at e r Quality

There ar e several actions that ca n b e taken to i m pr ov e w at er q ua li ty .Firstly, th e water quality i s already improved over natural

depressions because water i s washed from a relatively clean roof i ntoa covered tank, reducing th e pollutants washed i n t o th e water a nd t he

number o~insects that breed i n t h e t ank .

To maintain this w at e r q uali ty , th e gutters and th e roof should b ecleaned p e r i o d i c ally , especially just before th e onset o f th e r ai n yseason t o prevent leaves, d us t an d d e a d a n i m al s an d insects washing

i n t o t h e t ank .

I f th e tank i s not already e m p t y a t th e en d o f dr y season i t should b eemptied and any silt collected i n th e bottom should b e removed. Th einterior o f th e t an k should be cleaned with a brush.

The gap between the roof an d th e extension wall should b e closed with

stones an d mortar to keep ou t wind—blown material, lizards, birds an dinsects. T hi s w il l a ls o m in i mi z e evaporation losses. T he c hi ck enwire f il te r c an b e improved by attaching a length o f screen—mesh

across i t allowing water through but keeping insects out.

A clean an d e f f i c i e n t method o f drawing water from th e tank ca n b eadopted, th e b e s t b e i n g a hand—pump f i x ed n e xt t o th e e xt en si on w al lwith its suction p i p e f i x ed just above th e be d of t h e t ank . Below th e

hand—pump a 12 0 cm square platform o f stones should b e laid t o prevent

th e ground from getting swimpy from any spilled water. Th e hand—pump

should be locked with a padlock to prevent children playing with i t oru na ut ho ri se d u se a nd i t should b e kept i n good order with periodic

greasing.

1 2





C O N T R A C T O R S M A N UA L O N W A T ER T A N K S

CONTENT S

P A G E

CONTRACTORS MANUAL ON W A T ER T A N KS 1 3

CYLINDRICAL TANK, 2 1 c u b i c m e t re volume 14

1 . S i t e preparation 1 4

2 . Building instructions 1 5

EXTENDED GROUND TANK, 7 8 c u b i c m e t re volume 2 0

1 . S i t e preparation 2 0

2 . Building instructions 2 1

3. Quality control and maintenance g ui d e li n e s 2 9

4 . cleaning and management 3 0


1 . Manufacturing gutters 3 2

2 . Manufacturing V—shaped gutters 3 4

3. Installing V—shaped gutters 3 8

4 . Manufacturing square gutters 4 0

5 . I n s t alli n g square gutters 4 2

6 . Quality control an d maintenance 4 4

CONTRACTORS MANUAL ON HAND-PUMP 4 5

1 . The Hand—pump 4 6

2 . Mat e r i als f or t he Hand-pump Manufacturing 4 7

3 . Manufacturing Instrutions 4 8

4 . Installation o f Pum p a t erected Ground T an k 5 2

1 3





21 CUBIC M E T R E RAISED T A N K

300mm.roin s e a

P T P P T W / /7 V h 7 D / C O N S U M P T I O N2 1 ,60 0 litres180 c l a y s without m in

1 2 0 l i t res p e r d a y

metres

pe g

1 . Site Preparation

1.1 Positioning the Tank

a . Th e tank should b e sited n ex t to th e house. Measure 3 .05from th e wall and hammer a wooden peg into t h e g r oun d .

b . Ti e a wire to th e peg and make a small loop 2 05 cm from th e

cutting of f th e extra wi re. Put a long nail through th e loop.

c . Using th e nail, scratch a circle o n t he cleared ground around th e

pe g using th e wire radius o f 205 cm . T h i s c i rc l e o f diametre 4 10i s th e outline o f th e t a n k f o u n d at i o n .

d . D ig t he soil ou t from inside th e circle to a depth o f 1 5 cm usinga long spirit level t o m a ke s u re t he f l oo r o f th e excavation i shorizontal and even.

lO cm.de ep le ve l excavat~n

— 1

1 4





2 . Building Instructions

2 .1 Preparing th e B .R . C. W e ld M e sh F r am e

a . cu t tw o lengths o f 2 00 c m l on g an d 2 10 cm wide B.R.C. weld mesh.

P la ce t he m next t o e a ch o t he r w i th an overlap o f 1 0 cm s o that

th e square o f w el d m e sh i s 2 00 x 2 00 cm .

b . Ra m a pe g into th e centre o f th e square piece o f weld mesh. Tie

a string to t he p eg a nd draw a circle on th e w e ld m e sh that ha s a

radius o f 2 00 c m.

c . C ut t he w el d m e sh a l on g th e drawn circle line using a hammer an d

a chisel on hard st on e. T hi s s he et o f w e ld m e sh w il l b e used f orth e foundation o f th e water tank.

-cfllT‘—r200 —iWrr~

d400 I

d . Cu t one length

th e wall.

o f B . R. C. w el d m e sh 1 25 0 c m l on g t o be used for

e . With a string draw a circle onfoundation that ha s a radius o f 1 91 cm

th e ground away f rom th e

f . Placedrawnwire.

the 1 2 5 0 cm l on g w e l d m e sh upright a s a cylinder on the

circle with a radius o f 1 9 1 c m an d ti e i t t og et he r w it h

g . Bend t he l ow er e nd s o f weld mesh’s vertical ends outwards.

1 5





2 .2 Concreting the Foundation

This w or k m u st b e completed in on e d ay .

a . Mix c o n c re t e m a d e o f 1 portion of cement t o 3 portions o f clean,

coarse sand an d thereafter add 4 portions o f ballast(approximately 5 cm diametre stones) (1:3:4) and add water.

b . Pour a 5 cm t h i ck c o n c re t e mix into th e e x c av a t i on f o u n d at i o n and

compact i t well.

c . Place th e circular sheet o f w el d m e sh on top o f the m oi stconcrete.

d . Place th e cylindrical sheet o f w el d m e sh on to p o f th e circular

sheet o f w e ld m e sh an d ti e them t o g et h e r w i t h binding wire i n 3 0places.

e . Ti e th e w at er p i pe m a d e f r om g al va ni se dc i rc u la r w e ld m e sh an d th e wall.

iron p ip e onto th e

f . Mix concrete (1:3:4) an d pour i t i n a 5 cm thick layer onto th efirst layer o f concrete i n th e f o un d a ti o n. C om p ac t this secondl ay er well t o ensure that i t ha s a g o od b o nd w i th th e w eld m esh

underneath.

g . Keep th e c o n cr e t e m o i s t and covered for proper curing.

1 6





2.3 Lining the T a n k W i t h th e First Coat of Plaster

a . Roll on e layer o f 2 .5 cm chicken mesh, around th e outside o f th ecylindrical w e ld m e s h a s tightly a s p o s s i b le . Overlapping o f th e

chicken mesh should be a t least 1 5 cm .

b . Roll loops o f gauge 1 6 galvanised wire around th e chicken m e s h a stightly a s p o s s i b le . T he s e l oo p s o f wire should be spaced 1 0 cmapart.

~‘4”piping.

f l oo r and wall B R C pro pe r ly.

Se w t h e m t o g et h e r t o m ak e a lo n g

d . R oll t hi s blanket tightly around th e w el d m e sh an d th e chicken

m e s h s o t ha t al l of th e outside o f th e tank i s covered.

e . Ti e 5 0 rounds o f sisal string tightly around th e blanket o fs ac ks . S pa ce t he strings 4 t o 5 c m a p ar t .

f . Mix 1 portion o f c em e n t w i t h 3 portion o f clean, coarse s an d

( 1 :3 ) an d water.

g . S me ar th is m o i s t mixture onto th e inside o f th e blanket with a

trowel. This coat should be 3 t o 5 cm thick an d stick well t oth e chicken mesh al l over. Leave this coat o f mortar to hardenfor 1 2 hours.

~E7S

c . Cu t open 2 0 e m p t y su ga r sa cks.

blanket 2 00 c m wide.

1 7





2. 4 Lining th e T a nk W i t h a Second Coat o f Plaster

a . The following day, mix mortar ( 1 :3 ) an d apply i t to th e inside o fth e tank in a 3 c m t hi c k coat. Smooth i t evenly with a wooden

float.

b . Clean th e floor o f tank. Pour a 2 c m t hi ck l ay er o f mortar ( 1 :3 )onto th e clean, moist floor. Smooth i t with a wooden float.

c . Mi x cement w i th w a te r an d apply a t hi n c oa t o f this cement slurry

to th e moist plaster on th e i n s i d e o f th e tank wall an d floor.Press th e slurry into a plaster with a square s te el t ro we l. T hi s

will ensure a watertight coat. Th e coats o f plaster and cementslurry mu s t be completed in on e day.

a . On the following da y after lining t he i n si d e , remove th e sugarsack blanket f ro m t he outside o f th e tank, we t i t an d hang i t onth e inside o f th e tank for proper curing. La y polythene sheetingon th e floor o f th e tank an d cover i t with 3 cm o f water.

b . Plaster th e outside o f th e tank with a 3 c m t hi ck c oa t o f mortar( 1 :3 ) an d smooth i t with a wooden float.

c . Wrap th e outside o f t he t an k i n a s he et o f polythene sheeting an d

secure i t with sisal strings.

d . Keep th e f erro—cement tank moist an d covered for 3 weeks t oensure a good curing and a watertight tank.

2.3 Curing th e Lining and Coating th e Tank

1 8





2.5 Fixing the Roofing Timber

a . W at er t an ks should b e roofed t o reduce evaporationremove up to half th e water i n th e tank (evaporationASAL regions are m o re t h an 2 metres annually which i st o t he height o f this particular tank).

which ca n

rates i nequivalent

b . Place 5 lengths o f timber, 1 0 cm x 5 cm ( 4” x 2 ”) across t he t an k

an d space them 9 0 c m a p a rt . The timber should h av e b ee n t re at edwi th w ood preservative prior t o th e construction to stop i trotting i n t he m oi st environment. In coastal areas this ca n be

done b y soaking th e timber i n se a water for on e month. Tie th eends o f these timbers t o th e upper part o f th e wall reinforcementwith binding wire.

c . Place lengths o f timber, 1 0 cm x 5 cm between th e endsfirst 5 lengths o f timber and n ai l t h e m t o g et h e r w i t h 1 0nails. Leave tw o gaps, 1 2 cm wide, for the intakedownpipe gutters. Fi x a length o f timber and a f ra m e f or

hole i n th e roof structure.

a . N ail galvanized corrugated roofing sheets onto

structure. Trim th e sheets that protrude o ve r t hetank wall. R oo f t he li d o f th e man—hole and attach

metal t o ac t a s handles f or t he man—hole lid.

th e timberedge o f th e

tw o strips of

b . Close al l openings between th e iron sheets, th e timbers an d th e

edge o f t he t a nk with mortar ( 1 :4 ) t o k e e p l i z ar d s an d insectsout.

sheets

o fcm

of

a

the(4”)

th e

man-

2.6 Constructing t he R oo f

1 9





78 C U B I C M E T R E E X T E N D E D G R O U N D TANK

- -

Ave rage annua l ra ins811 m .m . —

//////

Daily_consumpjjg~

. i ñ7 , 0 66 t i t res 4 59 litres3 6 4 days

a . Th e tank should b e sited next t o th e house.wall and hammer a wooden peg i n to t he ground.

Measure 4 m from th e

b . Tie a wire t o t he p e g, make a s m al l l oo p 3 12 c m from th e pegcu t o ff t he extra wire. Pu t a long nail through th e loop.

an d

c . Using th e nail, scratch a circle o n t he cleared ground using th ew ir e r ad iu s o f 3 12 c m around the wooden peg. This circle o fdiameter 624 cm i s th e outline o f th e t a n k e x c a va t i on .

1. Site Preparation

1 .1 P os it io ni ng t h e Tank

2 0





1.2 Excavating the Tank

a . Di g o ut t he s oi l inside th e circle leaving some soil remainingaround th e centre peg. Us e th e radius wire a t al l ti mes to m ake

th e shape o f th e h a l f — ba l l e x c a va t i on . I f large s to n es p r ot r ud eou t o f t h e s i d e s, they ca n b e left a s part o f th e tank wall but

smaller stones should b e removed.

b . After excavating al l around th e pillar with th e centre

remove th e pillar a s t h e las t part o f th e excavation.

2 . Building Instructions

2.1 Applying the First Coat o f Plaster

peg,

a . Fill i n any holes left b y the stones removed

excavation with smaller stones and mortar m a d e from 1cement t o 5 portions o f sand (1:5).

during th e

portion o f

b . Starting a t th e bottom o f th e tank, throw a coat o f mortar,

consisting o f 1 portion o f cement t o 3 portions o f coarse sand(1:3), onto th e wall o f soil. Continue until th e plaster ha s

reached a thickness o f 2 .5 t o 3 cm . L ea v e t he plaster with arough surface a s i t makes a g o od b o nd for the n ex t coat o fplaster t o follow i n a couple o f days. Keep th e plaster moistan d covered with a polythene sheeting.

2 .5 cm . thick mo r taç1 :3 , p las te red o nto soil.

1 s t C oa t of Mortar.

2 1





2.2 Building the Tank R im Beam

a . Di g a 2 0 cm wide an d 2 0 c m . d e ep d i t ch a lo n g th e edge o f th e tankwall.

b . Fill th e bottom o f th e d i t ch w i th a 5 t o 7 c m l a ye r o f mortar

(1:3). Place 2 rounds o f barbed wire (gauge 16 ) on th e mortar.

c . Pour a second layer o f 5 to 7 cm o f mortar o ve r t he barbed wire

and compact i t well.

d . Placethat

beam.

another 2 rounds o f barbed wire (gauge 1 6 ) o n t he

all together there ar e 4 rounds o f uncut wire i nCu t th e barbed wire free from its roll.

mortar so

th e ring

e . Fill u p the d i t ch w i th mortar ( 1 :3 ) and compact i t well.

t he t op o f th e beam b y placing stones s et i n m o rt ar .Level

f . Keep th e r i ng b e am m o is t an d u n d er s h ad e for proper curing either

with polythene sheets o r sackcloth.

Ring-beam.

~i~nds o fba rbed wirearound alined s t ones .

2Ox2Ocm. r ing -beam re in f o rcedwith 4 r o unds o f barbed wire.

2 2





2.3 Extension o f th e T an k W al l

a . The extension wall, 6 5 cm high, i s b u i l t o n t o th e r i n g beam.

b . A ga p 100 cm w i d e an d 5 cm deep should b e le f t a t th e s i d ef u r th e st a w a y from the building to allo w overflow water out.

c . Th e wall ca n b e b ui lt o f stones se t i n mortar (1:4). Twelve

rounds o f barbed wire ar e d r aw n tightly around th e wall asreinforcement and covered with mortar/plaster (1:4).

d . Alternatively, bricks or blocks with a r i n g o f barbed wire ineach course ca n be used.

O ne r o und o f ba rbedwire in each course.

Extension of w aLL .

21





2. 4 Reinforcement o f th e Tank

a . N ail chicken m e sh w i th 2.5 cm n a il s o n to th e plaster o f th e tankwal l w ith 6 .3 5 c m (2.5”) nails. Us e we t nails a s i t makes i teasier t o hammer t h e m t h ro u gh th e plaster. Any overlapping o fth e chicken m e sh m u st b e a t least 1 0 cm wide. I f chicken mesh i snot available, barbed wire ca n b e used instead b y doubling th e

reinforcement o f barbed wire.

Ch ic ken w ire ,1 ”m e sh, n a i l e don t o th e i n te r i o r wal l .

.M lnim um cner lap1 0cm

Reinforcement

o f barbed wire, gauge 16 , onto th e interior o f th enailing th e wire a t th e bottom centre o f th e tank

upwards t o t h e t op edge o f th e tank. Spacinglines o f wire should b e 1 0— 15 c m a p ar t.

c . N ai l s ev en straight lines o f barbed wire, gauge 16 , across th e

tank passing o ve r t he bottom centre. Then n ai l another sevenstraight lines o f barbed w i r e a c ro s s t he t an k bottom a t a n angle

o f 9 0 degrees t o t he f i rs t seven lines. Then fi x lengths o fbarbed w i re f r om t he se l i n es straight u p t he s id es o f th e tank a sshown, nailed 2 0 c m a p a rt . I f chicken mesh i s not available,barbed wire ca n b e used instead i f th e spacing i s reduced t o 1 0cm .

b . N ail a spiraltank. Start

and continuebetween th e

Barbed ’w i r e na i l ed on t o wall in a spiral spac ed 20 cm .

2 4





lIDBarbed wire nai led o n to wall spac ed 20cm. apa r t

2.5 Applying the Second Coat of Plaster

a . this second and f i na l c oa t o f plaster has t oone day o r th e tank m i g ht c r ac k later on .materials, including water, ar e a t th e site

plaster.

b . Clean th e interior o f th e tank an d keep th e reinforcement a nd t hewall moist.

c . Throw mortar ( 1 :3 ) onto th e reinforced wall an d b e s ur e t h at i ti s embedded properly around th e r ei nf or ce me nt . T hi s plaster

layer should be 3 c m t hi ck s o t h at together with the f i rst coa t

o f plaster t he t o ta l thickness o f t he w a ll i s 5 . 5 c m. Smooth th e

plaster with a wooden f lo at u nt il a n even and uniform surface i s

obtained.

d . Fo r w at er p ro of i ng , a p p ly a c oa t o f cement slurry ( c em en t a nd

water Nil) with a square steel trowel . Coating with cementslurry must be completed within th e same da y a s th e f i n al c oa t o fplaster.

e . Cure th e plastered ferro—cement w o rk w i t h polythene sheeting an d

water fo r 2 t o 4 weeks. Failure t o d o s o will result i n a weaks t ru c tu r e w i th m a n y sma l l cra cks.

Final Coat of M o r tar .

be c ompleted with in

S o ensure that all

before starting t o

2.5cm thick m o r to r ,1 :3 ,

p las te red o ve r re in fo rcement

2 5





2.6 Building th e Overflow

a . Build a ramp o f bricks or ballast an d mortar against th e

extension wall o f th e tank leading u p t o t he 1 00 cm x 5 cm gap.I t should b e angled s o t ha t i ts base i s 3 m long and its widthshould b e 1 10 cm .

b . Plaster the surface and sides o f th e r am p w i th mortar (1:3).

c . Place two pieces o f timber 1 0 cm x 5 cm o n t he ramp, 5 cm i n fromeither edge a s a f or m —g ui d e. F il l this 5 cm between th e edge andth e timber with mortar to make th e sides o f th e overflow chute.

d . Place a n apron o f stones a t t he l o we r en d o f th e ramp and dig a

d i t ch d o wn to a hollow planted with f r ui t t r ee s .

Overflow ro m p o f bricks

or stonesand m or tar .

2 6





2.7 Fixing the Roofing Timber

a . Place a 3 .75 cm (1.5”) galvanized iron p i p e with f la t i ron s

welded to both ends upright i n th e bottom centre o f th e tank.Th e upper en d o f th e p i pe m u st b e about 2 0 cm l ower tha n the top

o f th e e xt en si on w al l i n order t o make th e tank roof sl op e

towards th e centre o f th e tank.

b . Place 2 lengths o f 1 0 cm x 5 cm ( 4” x 2 ” ) timber from wall t owall, resting o n t he f la t iron welded t o t he centre pipe. Al l

timbers should h a ve b e en treated w i t h w o o d preservative prior t oconstruction t o stop i t rotting i n t he m oi st environment. I ncoastal a re a s t hi s ca n b e done b y soaking th e timber i n s e a w at erf or on e m on th . T he se two timbers should b e placed about 2 0 cm

apart. N ail 2 layers o f chicken mesh between th e 2 timbers t o

act a s a sieve.

c . Place tw o more 1 0 cm x 5 cm pieces o f timber on either side o fthe f irst tw o timbers and space t h e m e a ch 1 50 cm from the f ir st

pieces.

d . Place another 2 lengths o f 1 0 cm timber on e a ch s i d e an d 1 5 0 cmfrom th e l a st t wo timber pieces.

e . U s e s t on e s , blocks o r bricks an d mortar to build u p t he extensionw al l s o t ha t i t reaches t he t op o f t h e t i m b e r.

f . Make a square man—hole measuring 6 0 x 6 0 cm between on e se t o fth e timbers nearest th e extension wall.

& grass

4’~2”t im be rs su ppo r t ed b yc e n t r e p o s t o f g a l v . i r o n p i p e .

Roofing and Sp i t E - o ve r .

2 7





2.8 Putting on th e Roof

a . N a il c or r ug a te d , galvaniz.ed roofing s h ee t s o n t o th e pieces of

timber. Leave a space o f 1 0 cm between th e end o f th e sheetsabove th e centre timbers to a l l ow r u n— o f f w a t er t o enter th e tankthrough t ha t s p ac e which i s covered with chicken mesh.

b . Cu t a hole i n t he roofing s he et f or t he m an —h ol e. M ak e a cover

f or t he man—hole o f 4 ” x 2 ” timbers a nd t he cu t piece o f roofing

sheet.

c . Trim th e roofing sheets a l on g t he o u te r e d ge o f th e tank. Fill

all the spaces between th e sheets and the t a nk w a ll with mortar(1:4).

d . Install a hand—pump next t o th e man hole.

Roofing ,Handpump and Gutters.

2 8





3. GENERAL Q U A L I T Y C O N T RO L A N D M A I N T E N A N C E G U I D E L I N E SThere ar e some general guidelines that must be followed to ensure

quality c ontrol and th e production o f leak—proof tanks.

3.1 Mortaring, Plastering an d Curing

I t i s o f great importance that al l coats o f plaster be completedwithin one day and that th e plaster mix and reinf orc ement a t al lstages a re t he same a s those listed i n th e building instructions. I fth e proportion o f cement in th e mix h as been reduced, either through afalse attempt a t economy o r through cheating then th e wall wi ll be

crumbly an d flake a f t er w e tt i n g. I f th e reinf orc ement h as beenimproperly made, large cracks ar e likely t o appear i n the tank. I fth e curing h as n ot been carried ou t effectively large numbers o f smallcracks will appear. Al l these f ault s ar e du e t o incorrect following

o f th e building instructions given. I f th e instructions are followedclosely then there should b e n o problems.

I f polythene sheeting i s not left over th e lining for long enough, an d

th e mortar no t k e p t m o i st , th e lining will dr y to o quickly an d cracksw i l l o c cu r i n many places.

I f cracks d o appear i n th e t a n k t h en depending on th e seriousness o fth e cracking several actions ca n b e t ak en .

I s th e lining crumbling of f th e t a n k w a ll ?

I f i t is , then th e mortar needs to b e removed and th e lining beguna g ai n f r o m scratch.

I s th e surf ace c overçd i n s m al l cracks?

I f i t i s t he n t hi s i s du e to to o rapid drying an d a ne w coat o fplaster can be applied with a second waterproofing. Curing should be

done properly this time.

Ar e there on e or tw o large cracks through w hi ch wa te r l ea ksou t of th e tank

I f there ar e t h en t h es e need t o b e chiseled ou t an d th e leakageblocked. Th e best method i s t o chisel a wa y 2 0 c m e i t he r side o f th e

c ra ck s o t ha t th e reinforcement i s exposed. Thereafter, 3 0 wide pieces

o f 5 cm x 5 cm ( 2 ” x 2 ” ) w e ld m e s h 120 cm long ar e nailed across th ecracks. Th e weld—mesh pieces must overlap a t th e e nd s b y a t least 1 5

cm . T he n c le an th e exposed area to b e replastered with water, an dthrow dr y cement d u st o n to th e moist surface. Le t this pure cementcoat dr y for a t l ea st f o ur hours before applying plaster consisting o f

mortar (1:3). A smooth complete coat o f plaster should be ap p li e dover th e crack an d onto th e wall o f th e tank around th e c ra ck . S m al l

cracks ca n be painted with bitumen paste.

2 9





4 . Cleaning and Management

There ar e several actions that ca n b e taken t o i m p ro ve w at e r q ua li t y.Firstly, th e water quality ‘ i s already improved over naturaldepressions because water i s washed from a relatively c le an r oof i ntoa covered tank, reducing th e pollutants washed i n to t he water and the

number o f insects that breed i n th e tank.

To maintain this w a t er q u al i ty , th e gutters and t he r oo f should b ec le an ed p e ri o d ic al l y, especially just before th e onset o f th e rainy

season to prevent leaves, dust, dead animals an d insects washing intoth e tank. there should be a chicken wire and screen—mesh f il te r o ve r

all the inlets an d t he t a nk overflow t o keep ou t pollutants an d stop

insects entering. Al l o r p ar t o f th e first rain o f th e s ea so n s ho ul db e diverted by moving th e downpipe s o t ha t i t d o es n ot flow in to the

tank.

I f th e tank i s not already empty a t th e en d o f dry season i t should beemptied and any silt collected i n th e bottom should b e removed. Th e

interior o f th e tank should b e cleaned with a brush.

I f there are any gaps between t he r o of an d th e extension wall, they

should be f illed w ith ston es an d mortar t o keep ou t wind-blown

material, lizards, birds an d i nsects. T hi s will a ls o m i ni m is e

evaporation losses.

Fo r th e extended ground ta nk, a clean and efficient method o f drawing

w at er f ro m th e tank c an b e adopted, t h e b e s t being a hand—pump fixed

next t o th e extension w a l l w i t h i ts suction p i p e f ix ed j ust a bove thebe d o f th e tank. Below th e hand—pump a 1 20 c m square platform o fstones should b e laid to prevent th e ground f r o m g e tt i n g swampy from

an y spilled wa ter. The hand—pump should b e blocked with a padlock t op r e ve n t c h i ld r e n playing with i t o r unauthorised use and i t should be

kept i n g oo d o rd e r w i t h regular maintenance.

30





C O N T R A C T O R S M A N U A L O N GUTTERS

CONTENTS

P A G E


1 . Manufacturing gutters 3 2

2 . Manufacturing V—shaped gutters 3 4

3 . Installing V—shaped gutters t o roofs 3 8

4 . Manufacturing square gutters 4 0

5 . Installing square gutters 4 2

6 . Quality control and maintenance 4 4

CONTRACTORS MANUAL ON HAND—PUMP 45

1 . Th e Hand-pump 4 6

2 . Materials f or t he Hand—pump Manufacturing 4 7

3 . Manufacturing Instructions 4 8

4 . Installation o f Pump a t Extended Ground Tank 5 2

3 1





1. Manufacturing Gutters

1.1 Ordinary Half—Circular Gutters

O r di n ar y h al f— ci rc ul ar gutters a re g en er al ly m an uf ac tu re d b ycommercial f ir ms i n cities a nd s ol d through b ui ld i ng s up pl ie rs . T he y

ar e rather expensive. Because they flatten—out with use an d ge t

d a m ag e d, t h ey may n ot b e a b le to t r a ns p o r t e n ou g h roof r u n— o f f l e ad i n g

to over—spill an d water loss. This i s common i n v e r y h e a vy showers.

T h i s p o t e n ti a l fo r water loss i n h e a vy s h ow e rs i s bad for rooftop run-

of f harvesting. I n addition, ordinary g u tt e rs m u s t b e nailed t o a

f aciaboard. Many buildings such a s schools do not h av e b oar ds an deven i f they do , this i s a difficult job.

Knowing these problems and because o f th e high cost o f buying semi-

circular gutters, tw o ne w t y p es o f gutter h a v e b e e n developed: th e

square gutter and th e v—shaped gutter.

Table 1 — Comparison Between Gutters

Type o f Gutter Holding Cost per

Capacity 1 metre

Ordinary half—circular gutter 7.5 litres KSh. 85/ —

(with 8 ” f aciaboard + paint)

Square gutter 9.5 litres K Sh . 4 0 /—(with 4 ” faciaboard + paint)

V—shape gutter 1 0 . 0 l i t re s K Sh . 3 9 /-

(with hangers and skirting)

1.2 The V—shape Gutter

T he v —s ha pe gu tt er i s recommended for a number o f g oo d r ea so ns . I thangs i n iron hangers f r o p t an iron sheet s k i rt i n g w h i ch i s nailed t oth e roof. Th e skirting i s important because i t directs al l run—offw ate r d ow n into th e gutter, preventing i t from flowing over th e edge

an d onto th e ground. The skirting should b e used f or a ll ty pes o fgutters and not just v—shaped ones.

Because i t transports a ll t he r u n— o f f w i t h n o losses i t i s good t o us ean d i s i n f act th e cheapest o f the three ty pes o f th e gutters

available.

32





Th e v—shaped gutt~rca n b e b u il t with a hand—operated gutter—bending

machine a s shown below. I t ca n b e made b y a local b la ck sm it h w ho h aswelding equipment for a b ou t U S $200.

However, a cheaper gutter—bending t oo l c an b e m a d e f or a bou t US $ 40 b y• a c a rp e n te r w i th b a si c tools. Although t hi s t oo l i s cheaper, i t does

take more time t o produce gutters and i f a large number o f gutters ar e

t o b e m a d e i t will b e better t o bu y th e hand—operated machine i n th elong run.

9 . 5

9,5’

220mm

-

I __j

~g’5

‘ 5

. 5

Hand l e we l de d onto n u t

Washer

I 9 , 5

Handle o n nut

33



t



2 . Manufacturing V—shaped gutters

2 .1 Making the gutters

a . Cu t 3 0 cm wide strips o f plain galvanized iron sheet,gauge 26 .

preferably

b . Screw a 280 cm b y 1 3 cm b y 3.5 cm piece o f t i m b er o n t o th e gutterbending tool a s shown below. T h e re a f t er , p l a c e on e o f th e 3 0 cmi r o n s h e et strips between th e gutter t oo l s o t ha t i t protrudes 2

cm out o f th e side t ha t d oe s n ot have th e e x tr a p i e ce o f woodscrewed on ( as shown below). Screw th e tw o timbers togethert ig ht ly . B en d th e protruding sheet d o wn wa rd s w it h a hammer and

a s h o rt p i e c e o f h a rd w oo d , b e in g c ar ef ul no t t o damage it .

I 2 8 Iil

First b e n d

1 2 0 o r a n w id th C ut t in g I r o n S h e e t s

E r

- i~t95~3~.QL

3 4





c . Unscrew th e timbers, p u ll o ut t he i r on s he et , t ur n i t around andinsert i t between th e t i m b er s w i t h th e bent edge pressed against

th e e x t r a p i e c e o f w o od a d d ed t o t he t wo tool timbers a s shown i nthe n ext p i ct ur e. S cr ew t he b o lt s d o wn a ga i n s o the i ron s he eti s held tight an d b e nd d o wn th e protruding sheet with th e hammer

an d piece o f hardwood.

shown i nprotrudingth e sheet

into a y —

G u t t e r

a

S e c o n d b e n d

d . Unscrew th e timbers again an d place th e iron sheet a st he n e x t picture. Tighten th e bolts an d then bend th e

2 cm ed ge o f th e sheet downwards a s before. Remove

from th e timbers a nd y ou c an se e i t h as n ow been madeshaped length o f gutter.

Third b e n d

/

3 5





e . Th e skirting i s m a d e t he s a me wa y a s th e gutters, th e only

differences being that:

( i ) th e width o f th e iron sheet strip ca n b e anything between 1 7

an d 3 0 cm ,

( ii ) a skirting needstimber from th epicture.

f . Th e sheet should b e inserted between t he t wo timbers s o that 5 cm

sticks o ut o n t he opposite side, th e bolts tightened, and th e 5c m edge bent d o w n w ar d s o n l y part o f th e way towards t he t i m b e r.

only on e bend an d only partly towards th ehorizontal a s shown i n th e following

Skirting

I M in. 1 2 I‘J’ \—

3 6





2.2 Manufacturing Gutter Hangers

Gutter hangers ar e produced f r o m 3 mm galvanized wire.

a . A profile o f a gutter hanger should be d r aw n o n to a s o li d pieceo f t i m b er s u c h a s a workbench a s shown i n t he n ex t pictures ( iti s a right—angled triangle).

b . Hammer 7 .5 c m n ai ls (3 ”) 3 cm d e ep i n to th e wood at th e cornersof th e triangle a s shown in th e n e x t p i c t ur e s. C ut t he h e ad s of fth e n ai ls an d f i l e t he c ut en d s o t ha t i t i s no t sharp an d

dangerous.

c . To m ak e th e h a n ge r s, b e n d 3 mm wire around th e n ai ls a s shown i nth e n e x t p i c tu r e.

sa,

G u tte r p r o f i l es’ /

s’s’

,Kb,’‘‘

s’ ‘

M -’Tna~lswith heads cu t o f t

/

3mm g a l v a n i z e d w ir eb e n d a rou n d gutter profile

1 , 5 mm ga l van i z e d wiretied to punched in

Gutter Hangers

3 7





3. 3 Installing V—shaped Gutters

Fo r triangular gutters t ha t d o no t need a f ac i ab o ar d follow these

instructions.

a . Gutters ar e f i x ed o n to e ac h side o f th e building. Th e slope o fth e gutters towards th e water tank should be such t ha t t h er e i s a

drop o f a t least 1 0 c m f or every 1 0 metres length.

b . First draw a b ui ld e r s line 2 cm from t he e d ge o f the roof for

ali g n m e n t o f t he skirting. Thereafter n a il t he s ki r ti n gs o n tothe roof with roofing n a il s ( w i th ou t removing the na ils i n th e

roof) fo r every 3 0 cm o r so. Ensure that th e b e n d o f th e

skirting i s following th e b ui ld e r s line. When th e whole lengtho f s ki rt in gs h av e b e en nailed o n to t he roof, then p un c h 3 mm

holes i n t he up p e r part o f th e vertical li p o f th e skirting forevery 9 5 cm starting from that en d which i s nearest th e water

tank.

h o l e s

Setting S lope

d . H an g u p th e f ir st a nd l as t gutter hangers on either end o fhouse (the on e n e ar t he t an k should b e 1 0 c m lower pe r 1 0 m

th e horizontal) by attaching i t with 3 mm galvanized wireshown in th e previous picture. Attach th e i nn er loop o fhanger t o the underside o f the roof either b y t y in g i t t onail holding down th e skirting o r t o th e purling.

th e

i na s

th eth e

F ix ing Gutter H a ng e r s

3 8





e . To hang th e other hangers, ti e a builders line between the two

e nd ha ng er s a nd carefully draw i t tight s o that i t shows th e lineth e gutter should take. When i t slopes 1 c m d o wn i n every 1 m

along, th e other h an ge rs c an b e f ix ed s o t ha t t he ir bottom angle

just touches th e line.

f . With gutters lengths b e i n g 200 cm , th e hangers are spaced 9 5a p ar t, s o t h a t every second hanger w il l s u p p or t a n overlap o fcm i n th e joints o f th e gutters.

g . When a ll t he gutter hangers are in position, f it t he lengths o fgutters into th e hangers. Start with th e gu tter nea rest th e tankan d c on ti nu e a wa y f ro m th e tank. Each next gutter should be

fitted s o that its lower (tank) en d sits o n to p o f th e previous

gutter length. They must overlap by 2 0 cm . Th e joint should si texactly in th e gutter hanger with 1 0 c m o f th e gutter overlap

either side. A thin coat o f bitumen i s smeared onto t he e nd o feach gutter l e ng t h b e f or e th e overlapping gutter i s laid onto it .This will create a water—tight seal.

h . Th e guttering i s extended t o th e water t an k b y gutters nailedonto tw o 1 0 cm x 2 .5 c m ( 4” x 1 ” ) t i m b er s f o rm i n g a V . The faren d o f th e gutter should b e closed by bending th e sides o f th e

gutter together and sealing with bitu men.

Gut te r26g . i ron sh e e t. 3 mm.wire.

Fixed g’attgwith thin wi re .

Gutters

.~LDPJPL(Gutter in V — tim ber ).

cm

20

411” timbers as support fo r

gu t te rs to tank

L a y in g

Skir t ing_ 2 5 g . i r on sheet .

3 9





4 . Manufacturing Square Gutters

4.1 Making th e Gutters

Th e benefits o f squ a re gu tters are:

— tha t som e people t hi n k t he y l oo k nicer tha n the v—shapedgutters,

— i f th e house already ha s f i x e d f a ci a b oa r d s then i t i s easier

t o fit squ a re gu tters than t o h an g V — s h ap e d gutters.

a . As with th e V—shaped gutters, put a 3 0 c m w id e strip o f iron

s he et ( ga ug e 2 6 ) between t he t wo timbers o f th e sheet—bending

tool so that 2 cm sticks o ut t he other side. Ben d thi s downagainst th e timber us i n g a hammer an d a piece o f ~hardwood.

I 2 8 I

cr2

First b e n d

of the iron—sheetb . Afterwards, b en d the oth er protruding part

u pwa rds a s shown i n th e picture below.

(II40 S e c o n d b e n d





c . L a st l y, b e nd th e e d ge t ha t sticks up past th e timber downwards i nth e direction o f th e timber a s shown i n th e following picture.

~‘°___

9 . 5 \ ) ‘ \

T h i r d b en d

1 1 5 s* ,

9 , s ~G u t t e r profile

« L —- — — -

3” nails withh e a ds c ut off

3m m ga lvan ized wireb e n d a r o u n d n ail s

in gu t te r profile

Gutter Brackets

2

s

d . Gutter brackets should be m a d e w i th 3 m m galvanized wire bentaround a profile o f th e bracket d r a wn o n to a s ol id p ie ce o ftimber such a s a workbench. Th e wire i s bent around 7 . 5 c m n a il swhich h a ve b e en knocked i n 3 c m deep and had t h e i r h e ad s cut—off

and f i le d smooth a s shown below.

1 , 5 mm ga lvan ized wiretied t o s h e e t

4 1





5 . Installing Square Gutters t o th e Roof

a . U s i n g U — n a i ls , f i x t he f i rs t gutter bracket t o th e faciaboard 1 0cm i n from t he e n d nearest t o th e water tank. I t must b e nailedt o th e lowest position possible on the faciaboard t o allow

maximum slope o f th e gutter towards th e tank.

b . Ti e th e bent circle i n th e gutter bracket t o a roofing nail

hammered i n to t he r oo f using 1 .5 m m galvanized wire. Afterwards,n ai l another bracket a t th e furthest en d o f th e f a c i ab o a rd , a g a in1 0 cm i n from th e end, but t hi s t im e a s high up o n th e faciaboard

a s p o ss ib le . W it h a good slope towards th e tank, th e gutter will

deliver a ll t he run—off water.

c . Check the sl op e between t he t wo gutter

builders li n e tightly between th e bottom

should have a t least 1 cm d r o p e v er y 1

check using a hosepipe level.

brackets b y drawing a

o f t he t w o brackets. I tm a lo ng w hi ch you ca n

d . Fi x the rest o f th e b r a c ke t s u s i n g th e builders line a s yourgu id e. The bottom o f th e bracket should j us t t ou ch t he buildersline. There should b e 2 0 c m overlap o f th e gutters an d s o i f th e

gutters lengths a re 2 00 c m l o ng th e hangers should b e spaced 9 5c m apart.

2

‘1 0 I

Gu t t e r .

Cx2’ timbers as su ppo r tfo r gutters to tank

Hang ing Squa re Gutters

Han ge r s t ied to nai lin roof with 1,5m m

galvan ized wire

Gut t e r s nai~dto fac iaboard

‘loi

Lii“e

‘~s

Gut t e r+4.1”timber

LIBracket. Skirting. Installation. Down-p ipe .

4 2



t



e . S t a r ti n g f r o m t he e nd nearest th e tank, gutters are laid into th ebrackets s o t ha t th e next gutter sits inside th e previous gutterwith a 2 0 cm overlap. Before placing th e next gutter down, th e

previous gutter should b e painted with bitumen s o that t hey m akea water tight seal. The overlap should centre exactly i n th e

b ra ck et , w i th e ac h g ut te r s t ic k in g ou t 1 0 cm either side.

f . Th e guttering i s connected t o t he t an k with a fe w lengths o fguttering supported b y 1 0 cm x 5 cm ( 4” x 2 ”) timbers. Th edownpipe g u tt e rs , w h i ch are similar t o th e gutters themselves,are nailed onto th e tw o lengths of timber fixed between the en ds

o f th e f aciaboards an d th e tank. Ensure t ha t t hes e downpipegutters extend some 2 0 c m i n to th e tank an d that joints to th e

gutters ar e w a te r ti g ht . T h er e should be 2 gutter lengths on each

d o w n p i p e s e ct i o n.

g . Th e far end o f th e gutter should b e closed b y bending th e sides

an d bottom together and bending th e 2 cm tongue over th e top.This should b e done before th e last length i s put i n th e hanger

an d i t should b e sealed w i t h b i t u m en .

h . To a v o i d s p i l l — ov e r o f run—off w a t er f r o m t he r oo f o f th e houseduring heavy storms, nail a skirting o f . iron s he ets o nt o th e

roof. The skirting w i l l d i r e ct all run—off i n to t he gutter.

Ga l van i z ed roo f ing sheets

4 3





6 . Quality Control and Maintenance

6.1 Guttering and Roofing

I f th e gutters have no t b e en h u ng p r op e rl y, w at e r ma y n ot flow down

efficiently towards th e t a nk i n l et . Instead i t may just build—up i nth e gutter and overflow onto th e ground alongside th e house.

D o e s w a t er c o ll e ct i n the gutters and f ai l to f low freely towards th etank?

I f this i s th e case, th e h an ger s n ee d t o b e suspended a t an

increasingly lo we r le ve l towards t he t a nk end o f th e roof.

I f th e gutters leak, then th e joints between each section o f gutteringneed a m o re e v en coat o f bitumen paste t o s ea l t he m t og et he r.

D oes w ate r d rai n awa y f ro m th e opening into th e t a nk o n ce i t flows

onto th e roof?

I f th e tank roofing does not d r a i n t o wa r d s th e centre o f th e tank i tneeds t o b e removed and repositioned s o t ha t i t does. This should n ot

happen i f th e correct height o f wall an d correct length o f galvanized

s u p p or t p i p e ha s been used.

3.2 T a k e— O u t P i p e s

With th e 2 1 c u b i c m e t r e raised tank, th e stand—pipe should b e well

sealed i n plaster but care should b e t a ke n n o t t o block i t with mortaror waterproofing. The f o l lo w i n g c h e ck must b e made;

D o es w at er f lo w out o f th e stand—pipe when yo u open th e tap?

I f water does not flow ou t o f th e p i p e w h en t he t a nk i s f ull thi smeans th e p i p e i s blocked. Th e ta p ca n b e unscrewed and a flexiblewire pushed through th e p i p e t o clear th e blockage.

a

4 4



a



CONTRACTORS MANUAL ON HAN D -PUMP

CONTENTS

P A G E

CONTRACTORS MANUAL ON HAN D -PUMP 4 5

1 . Th e Hand-pump 4 6

2 . Materials f o r t he Hand—pump Manufacturing 4 7

3 . . Manufacturing Instruction 4 8

4 . Installation o f Pump a t Extended Ground Tank 5 2

45





1. The Hand-pump

I n t hi s section i t i s explained how to manufacture a hand—pump f or uset o d r aw w a te r out o f an extended ground tank. I t ca n a ls o b e adapted

t o us e on a shallow lined well. Using a hand—pump i s much more

hygienic than taking water directly by hand o r b y rope an d bucketbecause i t prevents pollutants being introduced into th e w at er s ou rc e

through immersion o f vessels, an d allows f or t he water to b e sealedo ff f ro m t he outside b y a complete roof o r cover.

Th e tools required t o make th e hand-pump include;

1 di e stock 1 / 2 ” — 2 ”1 di e stock 2 . 5 ” — 4 ”1 p i p e v i ce1 engineering vice

1 hacksaw

1 hammer

1 centre punch1 bench drilling machine (hand1 4 m m d ri ll b it f or metal

1 5 m m d ri ll bi t for metal1 1 6 m m d ri ll bit for wood1 half—round 6 ” file

1 2 metre tape measure

2 adjustable spanners

or power driven)

Th e t ot a l c os t o f th e hand-pump i s roughly U S S 90.0

Hand P um p

4 6





2. Materials for t,he Hand-pump Manufacture

This diagram d e s c r i b e the p a rts o f th e hand—pump. Th e part numbers refer

t o th e order they ar e discussed i n th e f ol lo wi n g i n st ru ct io ns . T he y ar elisted b e lo w a l on g w i th their d i m e n s i o n s an d th e quantity o f each required;

Dimensions Quantity

1

2

34

5

67

8

91 01 11 2

1 31 41 51 61 71 81 92 02 12 223

2 42 6

2 72 82 93 0

G.I. nipple

R o un d nailG.I. p i p e

Me t al washer

Leather washer

Reducing socketRubber ball

G. I p i p e class B

PV C p i p e c la ss CG. I p i p e c la ss A

Rubber discsReducing socket

PV C p i p eG. I p i p eReducing socket

Wooden p lug

H e x ag o n al nipple

Rubber ballReducing socket

G .I . p i peG.I. socket

G.I. p i p e

S p r i n gG.I. p i p e

Plastic h o s e p i p e

G. I ca pTermite p r oo f p o st s

T i m b e r

Nuts an d bolts

1”

4 ”1.25” x 4 cm53 m m x 33 m m

100 m m x 3 0 m m

1 ” x 1 /2 ”2 2 m

1/2” x 4 5 0 cm

2 ” x 8 0 cm2 .5 ” x 7 0 cm

7 8 mm x 2 8 mm2 . 5 ” x 3/4”

1.5 ” x 1 5 cm2 ” x 2 0 cm2 ” x 3/4”

2 ” x 4 ”3/4”

34 mm

2 . 5 ” x 1 ”1 ” x 34 0 c m1 ”1 ” x 5 cm

1” x 5 cm1 /2 ” x 1 5 cm3 /4” x 135 cm

1/2”110 cm

4” x 21 / 2”

1

2

22

2

21

1

11

21

1

11

1

1

1

11

1

11

21

1

2

3

2

Number Part N a m e

47





3 . Manufacturing Instructions

Th e Piston

a . D rill a 4 m m h ol e i n th e middle o f

a 1 ” nipple ( 1 ) . Fi x a round 4 ”nail ( 2 ) into the hole. Cut the

protruding ends o f the nail off afew millimetres from the s id es of

th e nipple a nd r iv et t he e nd s with

a hammer.

b . Cu t a 4 c m long length o f 1. 25”

G.I. p i p e ( 3 ) an d push i t over th enipple ( 1 ) . I t will function a s a

spacer between the two leather

seals.

c.~ Push tw o metal washers ( 4) , withouter an d inner diametres o f 5 3 mm

an d 3 3 mm, over th e ends o f th e

nipple ( 1 ) .

d . Cu t 2 l ea th er w as he rs ( 5 ) withinner an d o u te r d i a m et r es o f 1 00 m m

an d 3 0 m m o ut o f 3 t o 4 m m thickleather. Soak the washers

overnight i n water an d then putthem into boiling oil for a few

minutes. Reduce th e o u te r d i a m et r et o 5 0 m m b y pushing th e leatherwashers through a 5 0 mm ( 2 ” ) steel

pipe an d leaving them i n s i d e i tovernight. Fi x the two cuppedseals over th e n i p p le ( 1 ) an d

ag ai n s t the meta l washers ( 5 ) withth e m ore op en en d o f th e cupped

seals f ac i n g away f r om t he n i p p le .

e . Wrap sealing tape around both ends

6 o f th e nipple ( 1 ) an d screw areducing socket 1 ” t o 1/2 ( 6 ) onone end o f th e n i p p le .

f . Pu t a rubber ball with a diametreo f 2 2 m m ( 7 ) i n to t he open en d o fth e nipple ( 1 ) t o ac t a s a valvean d screw another reducing socket

1 ” t o 1/2” onto th e open en d o f th e

nippl e.

g . Screw a 45 0 cm length o f p i p e ( 8 )onto this piston t o ac t a s a pumprod.

48





The Cylinder

a . Cu t a n 8 0 cm length o f 2 ” PV C pipeclass C ( 9 ) for a p um p c yl in d er .D rill a 4 m m hole 6 0 m m from on e

- en d o f th e pipe. Fi x a round 4 ”

nail ( 2 ) i n to t hi s hole an d rivetits ends with a hammer a s before.

b . Cu t a 7 0 c m l e n gt h o f 2. 5” G. I.

p i p e ( 1 0 ) for h ou si ng a nd makethreads at b o th e n ds o f it .

c . Cu t ou t a rubber washer 5 mm thickan d with an outer an d inner

diametre of 7 8 mm an d 2 8 mm ( 1 1 )from a n ol d tyre. Place thiswasher i n a reducing socket 2 .5” t o3 / 4 ” ( 1 2 ) an d screw this socket

onto on e en d o f t he 2 . 5 G.I. p i p e( 1 0) .

17

The Filter

15 a . Cut a 1 5 cm length o f 1 .5” PV C p i p ean d cu t many slots i n th e side o fth e p i p e ( 1 3 ) a s a f i n e f i lt er .

b . Cut a 2 0 cm length o f 2 ” G.I. p i p e1 3 ( 1 4 ) an d thread i t a t on e end.

D rill 3 2 holes o f 5 mm diametre

into th e side o f th e 2 ” 0. 1. pi pe

a s a coarse filter.

c. Screw a reducing socket 2 ” t o 3/4”

( 1 5 ) onto th e threaded en d o f th e

2 ” G.I. p i p e ( 1 4) .

d. Insert th e slotted PV C p i p e ( 1 3 )into th e 2 ” 0.1. p i p e ( 1 4 ) an d

Ç - - close its open en d with a woodeno Çl--o~ plug (16). N ail th e wooden plug

o into its position through th e

drilled holes in th e 0.1. pipe.

r N ail a disc o f a n ol d tyre onto th eV plug end.





Assembly o f th e Pumphouse and Filter

a . D rop a rubber b a ll w i th a diametre o fm m ( 1 8 ) into th e p u m p h o us e s o t ha t

rests i n th e centre i t th e bottom.

c . Push th e piston and p u m p ro d ( 8 ) into

th e PV C cylinder ( 9) .

d . Close th e c yl in d er w it h a reducingsocket 2 . 5 ” t o 1 ” ( 1 9 ) with a rubber

disc placed inside it . Th e r ub be r d i sc s

keep th e PV C cylinder i n place.

e . Cu t a 3 40 cm length o f 1 ” 0.1. p i p e an dthread i t a t both ends ( 2 0) . Thereafter,

push i t over th e p u m p ro d ( 8 ) an d screw

i t i n to t he reduction socket ( 1 9) .

f . Connect th e filter t o th e p u m p h o u se w i t ha 3 / 4 ” hexagonal nipple ( 1 7) .

3 4it

b . Push th e PV C

pumphouse withball t o ac t a s

cylinder ( 9 ) in to theth e nail n e ar t he rubber

a stopper.

H -

r; tH\

i

KcF -NJW ‘U

5 0





Th e Handle and Raiser Pipe

l o c ka b l e c h a i n welded

b . Cu t a 5 cm length o f 1 ” 0.1. p i p e w i t h on e threaded end and screwi t i n t o t he 1 ” socket ( 2 2 )

c . Place a spring 5 0 m m x 1 2 mm ( 2 3 ) from a lorry engine va lve on to

th e p u m p ro d ( 8 ) s o that i t rests o n th e en d o f th e raiser pipe.

d . Screw a 1 /2 ” G .I . te e ( 2 4 ) onto th e pumping rod ( 8) . Screw tw o

1 5 c m lengths o f 0.1 . p i p e ( 2 5 ) into t he t wo o pe n e nd s o f t he t e e

( 2 4)

e . Push a 1 2 cm length o f 3 / 4 ” plastic p i p e ( 2 6 ) o ve r o n e o f th e

handles ( 2 5 ) an d close its en d with a ca p o f 1 / 2 ” G.I. ( 2 7) .Push a 1 20 c m length o f 3 / 4 ” plastic p i p e ( 2 8 ) over the ot he rhandle t o ac t a s th e delivery pipe.

Testing

Th e f u ll y a s se m b le d p u m p should b e secured t o a p u m p s t an d m ad e f romtermite p ro of p os ts a nd 4 ” x 2 ” timber s o t ha t i ts l ow er en d i s i n th e

ground—tank and tested t o se e i f i t works properly. ( Wh ere the p um p

i s fitted t o a well, t he l o we r end should b e far enough down t o reach

th e bottom o f th e well an d h e nc e p u m p th e water).

23

a . Screw a 1 ” s o ck e t w i t h ~ 2 0 c m l on g s te el

t o i t onto th e r ai se r p i p e ( 2 1 ) .

51





4 . Installation o f Pump at Extended Ground tank

a . Place th e p u m p s t an d i n a n excavation 6 0 cm x 6 0 cm x 6 0 cm- ‘ next t o th e edge o f a ground tank a t a c o n v en i e n t p l a c e f or

drawing water.

Erect th e p u m p s ta n d vertically an d horizontally with th e

slot pointing towards th e centre o f t he w at er tank. F il l u pth e excavation w i t h c o n cr e t e 1:4 an d stones.

b . Wrap a strip o f an old tube approximately 2 metrestightly around th e upper en d o f th e raiser p i p e ( 1 8) .

long,

c . Pu t t h e lo we r en d o f th e p u mp i nt o th e bottom centre o f th e

ground tank an d place th e rubber—wrapped end o f th e p u m p

i n t he s lo t between t he t wo t i m b er s w i t h bolts. Tighten th e

slot until th e r a is e r p i p e o f th e p u m p i s held firmly i nplace.

6 0

H

I ; : 15

I u ‘-‘ ~ i s

L . ii ‘ 1 1 0

P u m p S t a n d

1 0 1 0

wrops

5 2



I





Documents

Water tanks with guttering and hand-pump