roof water harvesting

8/6/2019 Roof Water Harvesting

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Draft, IWMI and SARI1

APPRAISAL OF ROOF WATER HARVESTING

AND ITS POTENTIAL FOR PRODUCTIVE

USES IN NORTHERN GHANA


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TABLEOFCONTENTS

ACRONYMSAND

ABBREVIATIONS1

CHAPTERONE 4

INTRODUCTION 4

1.1BACKGROUND .................................................................................................................................... 4

1.2.THEEXTENTOFWATERPROBLEMSWHERERAINWATERHARVESTINGSYSTEMSAREUSED .. 6

1.3GLOBALUSEOFRAINWATERHARVESTINGINSOLVINGWATERPROBLEMS...............................7

CHAPTERTWO 10

REVIEWOFROOFWATERHARVESTING.....10

2.1ROOFWATERHARVESTING ............................................................................................................ 10

2.2IMPORTANCEFORDOMESTICWATERSUPPLIES ........................................................................... 10

2.3RAINWATERHARVESTINGCOMPONENTS ..................................................................................... 11

2.3.1CatchmentSubsystem ............................................................................................................ 11

2.3.2ConveyanceSubsystem .......................................................................................................... 12

2.3.4StorageSubsystem .................................................................................................................. 13

2.3.4FilteringSubsystem ................................................................................................................ 19

2.3.5Distribution ............................................................................................................................. 19

2.4WATERQUALITYOFROOFTOPRAINWATERHARVESTINGSYSTEMS ......................................... 20

2.6SITEANDRAINWATERHARVESTINGSYSTEMSELECTION........................................................... 222.6.1Rainfall..................................................................................................................................... 22

2.6.2HydrologyandWaterResources .......................................................................................... 23

2.6.3SocioEconomicandInfrastructureConditions................................................................. 23

2.6.4EnvironmentalandEcologicalImpacts .............................................................................. 23

2.6.5Costs ......................................................................................................................................... 24

2.7WaterBalanceandSystemSizing........................................................................................... 24

2.7.1SupplyCalculation ................................................................................................................. 25

2.7.2DemandCalculation............................................................................................................... 25

2.7.3StorageCapacityCalculation............................................................................................... 26

2.8POTENTIALEFFECTSANDIMPACTSTAKINGALIVELIHOODSBASEDAPPROACH.................. 27

2.8.1ReductionofBurdensofthePoor......................................................................................... 282.8.2HealthImpacts........................................................................................................................ 28

2.8.3EconomicImpacts................................................................................................................... 30

2.8.4PovertyAlleviation ................................................................................................................ 30

2.8.5EnvironmentalBenefits.......................................................................................................... 31

2.8.6DomesticandIndustrialBenefits......................................................................................... 31

2.9PLANNINGANDMANAGEMENTOFRAINWATERHARVESTINGSYSTEM....................................31

3.THECASEOFNORTHERNGHANA.3


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REFERENCES ..33

AcronymsandAbbreviations

AEZ AgroEcologicalZone

ASA AridandSemiarid

DRWH DomesticRainwaterHarvesting

DTU DevelopmentTechnologyUnit

FAO FoodandAgricultureOrganizationoftheUnitedNations

IDRC InternationalDevelopmentResearchCentre

IWMI InternationalWaterManagementInstitute

MDGs MillenniumDevelopmentGoals

MLGLH MinistryofLocalGovernment,LandandHousing,Botswana

PAF AgroForestryProject

PRAs PrincipalResearchAreas

RHAZ RainwaterharvestingAssociationofZimbabwe

RWH RainwaterHarvesting

RWHS RoofWaterHarvestingSystem

SARI SavannaAgriculturalResearchInstitute

SSA SubSaharanAfrica

SIDS SmallIslandDevelopingCountries

SIWI StockholmInternationalWaterInstituteUNICEF UnitedNationChildrensFund

UNEP UnitedNationsEnvironmentProgramme

UNCESCR United Nations Committee on Economic, Social and Cultural

Rights

WH WaterHarvesting

WHO WorldHealthOrganization


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CHAPTERONE

INTRODUCTION

1.1Background

Water is fundamental for life and health. The human right to water is

indispensableforleadingahealthylifeinhumandignity.Itisaprerequisiteto

the realization of all other human rights (UNCESCR, 2002). In spite of this, a

largeproportionoftheworldspopulationdoesnothaveaccesstosafesourcesof

water.WHO/UNICEFhasestimatedthat1.1billionpeopledonothaveaccessto

improveddrinkingwatersources(WHO/UNICEF2000).

Despite major efforts to deliver safe, piped, community water to the worlds

population, the reality is that water supplies delivering safe water will notbe

available to all people in the near future. The Millennium Declarationby the

WHO established a goal of halving the proportion of the global population

withoutaccesstosafewaterby2015.Itisclearthatallpossibleapproachesmust


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be tried to mitigate the problem of drinking water, maximizing the control of

householdswithregardtotheirownwatersecurity.

In thiscontext,rainwaterharvesting isreceiving increasedattentionworldwide

as an alternative source of drinking water. Rainwater harvesting hasbeen a

popular technique in many part of the world, especially in arid and semiarid

regions (almost30%of theearthssurface).Rainwaterharvestingwas invented

independently in various parts of the world and on different continents

thousands of years ago. It was especially used and spread in semiarid areas

where rainfall occurs during some months and at different locations. The

application of appropriate rainwater harvesting system can make possible the

utilization of rainwater as a valuable and in many cases, necessary water

resources. Rainwater harvesting hasbeen practiced for more than 4000 years,

and, inmostdevelopingcountries, isbecomingessentialowingtothetemporal

and spatial variability of rainfall. Rainwater harvesting is necessary in areas

having significant rainfall but lacking any kind of conventional, centralizedgovernmentsupplysystem,andinareaswheregoodqualityfreshsurfacewater

orgroundwaterislacking

Whilerainwatermaybeharvestedinanumberofways,thispaperfocusesonly

on the collection and storage of rainwater from individual household roof

catchments. Traditionally this was the major option to people in waterscarce

regions in rural areas of developing countries where people had to manage to

fulfildrinkingwaterandhouseholdwaterneedsbyrainwaterharvesting.

Governmental

agencies

across

the

world

are

now

introducing

policies

to

promoteincreaseduseofrainwater.

InIndia,forexample,severalstategovernmentshaveintroducedlegislationthat

makesitobligatorytoincorporaterooftoprainwaterharvestingsystemsinnewly

constructedbuildings inurbanareas.(MeeraandMansoor,2006)Governments

arealsoprovidingsubsidiestopromotetheuseofrainwaterharvestingsystems.

The Ghana Science Association, GSA organized workshop on the theme:

Rainwater Harvesting: A sustainable Solution to Water Shortage Problems in

Ghanatocreateforumforcrossfertilizationofideasamongstakeholdersonthe

subjectwithaviewtoevaluatingrainwaterharvestingasasustainablepractical

solutiontotheperennialwatershortageproblemsinthecountry.(DailyGraphic,

2006).InGhana,rainwaterharvesting isbeingpracticedespeciallyatTemaand

someplaces intheNorthernsectorfordomesticpurposesbutthetechnology is

notfullydevelopedforagriculturaluse.(Anane,2000)

RWH technology is low cost and simple. RWH technologies have a high

potential of contributing towards the Millennium Development Goals (MDGs)

withaviewoferadicatingpovertyandhunger,provisionofsafedrinkingwater


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andsanitation,ensuringenvironmentalsustainability,promotinggenderequity

andwomenempowerment. It isonewayof improving the livingconditionsof

millions of people, particularly those living in the dry areas. Water scarcity

especially for domestic and agricultural purposes compromises the role of

women in foodproduction.Hence,provisionofwaterbypromoting rainwater

harvesting and management technologies reduces theburden for rural women

thus increasing their productivity. The provision of water at the point of

consumptionfromrainwatertanksprovidesarangeofimmediatepositivesocial

impactsonhealth,familywelfareanddomesticproductivity.Thisresultswhen

time saved in water collection is utilized elsewhere. Some of the time saved

maybe used for productive activities such as agriculture with clearly tangible

and easily valued economicbenefits. More time can alsobe spent on activities

suchaschild rearingwhenwomenhave time freedup from thedailychoreof

watercollection.Thevalueofsuchbenefitstofamily livelihoodandwellbeing

aredifficulttoassessandarerarelyappropriatelycosted.

Theaimofthispaperistocreateawarenessofsuccessfulmethodsorsystemsof

roof water that resource poor farming households have effectively used to

overcomethehardshipsofnature.

1.2.TheExtentofWaterProblemsWhereRainwaterHarvestingSystemsAre

Used

SuccessfulapplicationsofthisdomesticrainwaterharvestingareusedinAmman

(Jordan), Edlib and Quneitra (Syria), West Bank highlands (Palestine) and

Lebanon, where annual rainfall variesbetween 300500 mm. The practice was

alsohistoricallyused indrierclimates inYemen (Aden)andSyria (Rasafe). In

the semiarid zones of West Asia, about 6580% of the annual rainfall occurs

duringanapproximatelyfourmonthperiod,withtheremainingmonthshaving

littleornorainfall.Accordingly,rainwaterharvesting fromresidentialrooftops

representsaviablealternativeundercertainnaturalanddemographicconditions

this will help solve the problem of inadequate domestic water during the dry

seasonandthroughoutthewholeyear.(UNEP,2000b).

Katsukunye about 170 kilometre (km) away from Harare, Zimbabwe was well

known forperennialwatershortage.As thefunctioningof the localschooland

clinic also started getting adversely affected, the Ministry of Health and Child

Welfare was on the verge of closing down. However, the communitys

endeavourtoharnessrainwaterandevolverulesforitssustainablemanagement

issavingseverallives,everyday.About120peopleintheclinicand700students


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areitsmainbeneficiaries.Earlier,absenceofrainwaterharvesting(RWH)system

andadversehydrogeologicalfeatureslikerockyterrainandsalinegroundwater

hadintensifiedthecrisis.Pregnantwomenwerethemostaffected,asthepotable

drinking water source was almost three km away. (Catch Water, GWP News,

2003)

KookiCounty inUgandahasverydifficultphysicalandclimaticconditionsfor

drinkingwatersupplies.Aprogrammetointroducesimplerainwaterharvesting

techniques in selected households has successfully prompted replication

throughoutthedistrictonaselffinancingbasis.(OneWorldAfrica,2004)

1.3GlobaluseofRainwaterHarvestinginSolvingWaterProblems

SriLanka is one place that rainwater is harvested for domestic purpose. Sri

Lanka is classified as a country with little or no water scarcity. However, thepicturehasbeenmadeclearerbyanotherclassificationthatdividedthatcountry

into absolute water scarce districts and economic water scarce districts

depending on seasonality. Absolute water scarcity in this instance has been

defined as when water abstraction is more than 50% of available water.

According to this classification almost all dry regions in Sri Lanka face year

round or absolute water scarce conditions. Economic scarcity has on the hand

beendefinedintermsofthemagnitudeoffuturedevelopment.Therainwateris

usedforseveraldomesticactivitiesincludingflushingoftoilet,washing,cooking

anddrinking(occasionally)(LankaForum,1999).

MvuramanziTrust,amemberofRainwaterharvestingAssociationofZimbabwe

(RHAZ) with community participation constructed a 192 square metres

catchmentwith15cubicmetrestorage tankusinggraniterocksnear theschool

on a smooth rock surface for the Katsukunye Community in 2001. The project

has provided significant economic and environmental gains. A marked

improvementhasalsobeennotedinthechildrensschoolperformance.Casesof

diarrhoeaandunhygienicchilddeliveryhavereducedconsiderably.Thewomen

now have more time to invest in productive ventures. Adequate gully control

measureshavehelpedtocontrolenvironmentaldegradationaroundthegraniterocks.

Rainwater harvesting is used extensively in Latin America and the Caribbean,

mainly for domestic water supply and, in some instances for agriculture and

livestocksuppliesonasmallscale.InBrazilandArgentina,rainwaterharvesting

ispracticed insemiaridregions. InCentralAmericancountries likeHonduras,


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Costa Rica, Guatemala, and El Salvador, rainwater harvesting using rooftop is

employedextensivelyinruralareas.

Estimates show that about 100,000 people in ruralJamaica depend to a large

extent on rainwater harvesting (UNEP, 1997). Domestic rainwater harvesting

technologywidelyappliedinareasofWestAsiawheretheannualrainfallrangesbetween 350500 mm, especially in the mountainous terrain of Syria, Lebanon,

Jordan,PalestineandYemenhasbeenveryhelpful.Ithasalsobeenappliedtoa

certain extent in Saudi Arabia and the Sultanate of Oman.The eastern

Mediterraneanhills,whichreceiveahighrainfallquantityof5001000mm/year,

also resort to this technology due to the deep groundwater aquifer, the non

uniformspatialdistributionoftherainfallduetothewidespreadkarststructures,

andthehighvelocityofsurfaceandsubsurfacewaterrunoff.Thisresultsinthe

high availabilityof waterduring the rain seasons and in waterscarcityduring

the dry seasons.Domestic rainwater harvesting has helped households obtain

waterformostpartsoftheyear.(UNEP,2000b).

Rainwater collection systems are extensively usedby most SIDS, (Small Island

Developing Countries) especially those lowlying islands where rainwater

catchmentsconstitutethemajorpartofthewatersupplyfortheinhabitants.This

supplywilloftenbesupplementedbygroundwater.SomeoftheIslandsinclude

St.Lucia,theTurksandCalicosIslands.Insomeplacesgovernmentregulations

makeitmandatoryfordeveloperstobuildrainwaterstoragetanks.Rooftopand

purposebuiltcatchmentsalsoarecommonplaceintheBahamas.Onesettlement

(Whale Cay) has apiped distributionsystembased on rooftopcollected water.

OnNewProvidence,mostoftheolderhousescollectrooftoprainwaterandstore

it in tanks averaging 70000 litres capacity. Industrial use of rooftopcollected

rainwaterisalsopracticed.TheIslasdelaBahia,offthecoastofHonduras,meets

a substantial proportion of their potablewater needs from rooftop catchments.

Rainwatercatchmentsystemsarepractically thesolewatersupplysourcefora

smallgroupofislandsnorthofVenezuela;thesearidislandsexperienceonly500

mmto700mmofrainfallperyear,andhavelargelysalinegroundwaterreserves

thatcannotbeusedforpotablepurposes(UNEP,2000c).

Ethiopia is also one country that roof water harvesting hasbeen practiced for

some time due to the incidence of dry spells which results in undesirable

consequencessuchasfamineandshortageofwaterforotherdomesticactivities.

In high land areas where the terrain is rugged with scattered villages and

hamletsdevelopingmodernwatersupplysystemsisaproblem.Asaresultroof

waterharvestinghasbeenconsideredasaviabledevelopmentoption.Itisalsoa

meansofwatersupplyinareaswheregroundwaterisnotfeasibleandperennial


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streams/rivers do not exist. Roof water from schools, churches and individual

homeswithcorrugatedroofsareundertrialinseveralareasandtheresultssofar

are very encouraging. Adequate water is therefore provided during the rainy

season, an occasion where the rural communities arebusy with their farming.

Moreandmorepeopleareharvestingroofwater,asmoreandmorepeopleown

houseswithcorrugatedroofs(Alem,1999).

Due to inadequate piped water supplies, the University of Dar es Salaam has

appliedrainwaterharvestingandutilisationtechnologytosupplementthepiped

water supply in some of the newlybuilt staff housing. Similarly, rainwater is

collected from the hipped roof made with corrugated iron sheets and led into

twotanks,eachwitha70litrecapacity.Thetownanddistrictcouncilsunderthe

Ministry of Local Government, Land and Housing (MLGLH) have constructed

thousandsofroofcatchmentand tanksystemsatanumberofprimaryschools,

healthclinicsandgovernmenthousesthroughoutBotswana.(UNEP,2000)

DomesticroofwaterharvestinginthecontextofSouthAsiaandEastAfricawere

initiatedasasourceofdomesticwaterespeciallyfordrinkingandcooking.This

was mainly due to the belief that quality of rainwater is better than the

commonly found ground water. However, stored water is used for various

activitiesotherthandrinkingandcooking.This infactwasquiteevident inthe

SriLankanrainwaterharvestingprogramme,especially in thewetzone,where

stored water are mainly used for nonpremium water use activities (washing

clothes,sanitarypurposes,livestockandsmallscalehomegardening).Thisgave

the users the added advantage of having a source of water within accessible

distance for household use. Experiments conducted in Sri Lanka and Rwanda

indicate that improving accessibility of water has increased the per capita

consumptionofwaterandincreasedtherainwatercontributioninthetotaluseof

ruralhouseholds.StudiesconductedbytheAnawanTrustinTiruchendurTaluk

onroofwaterharvestingfromcommunitycenters,amongcoastalfishingvillages,

indicatedthatharvestedrainwaterhasparticularlybenefitedchildren,and80%

ofthepeopleintheareasaidthatwatershortageinsummerhasbeenovercome

byroofwaterharvesting.(MilestoneReportD5,2001).


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CHAPTERTWO

REVIEW

2.1RoofWaterHarvesting

Roofwaterharvestingisthecollectingofrunoffduringrainsfromimpermeable

surfaces on houses or close to houses, its storage in waterproof vessels and its

subsequentuseasthewatersupplyoftheinhabitantsofthehouses.Theusemay

be temporary (for example during the 24 hours following a rainstorm),

seasonal (throughout the rainy season)orpermanent (throughout theyear

except perhaps in years of exceptionally low rainfall. Rooftop rainwater

harvesting for household use will only ever represent a small part of the total

waterbalances.Inareaswithsignificantvariationsintheannualrainfallpattern,matching water supply and demand maybe difficult. However, in terms of

economicandhumanwelfareithasacrucialroletoplay.Rainwaterisinmany

cases theeasiest toaccess,mostreliable,and leastpollutedsource, inaddition,

because it can be collected and controlled by the individual household or

community as it is not open to abuse by other users. Rainwater

pollution/contamination may result from air pollution and biological

contamination.

2.2

Importance

for

Domestic

Water

Supplies

Rainwaterharvestingsystemshaveahighpotential inmanycountriesandare

alreadybeing widely used not only in ASA environments. Rooftop rainwater

harvestinghasanumberofpotentialbenefitsincluding:

1. Thewatersourceisclosetopeople,soitrequiresaminimumofenergyto

collectitandthereforeitisveryconvenient.

2. A reduction of the burden of collecting water over long distances;

particularlyforwomen

3. Improved health due to cleaner water, improved sanitation, reduced

drudgery (previous point), and improved nutrition (through growing

vegetables)

4. Reduction in vulnerability to external shocks such as drought, and a

diversification of livelihoods due to productive and economically

beneficialusesofwater


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farebestduetotheirrelativesmoothness(Fujioka,1993)andthesterilisingeffect

of the metal roof heating under the sun (Vasudevan, Tandon, Krishnan, &

Thomas,2001).

Catchmentsincludenaturalslopesorsealedcatchments,rocks,roofs,roadsand

floodwaterfromseasonalrivers

RooftopCatchments

Inthemostbasicformofthistechnology,rainwateriscollectedinsimplevessels

at the edge of the roof. Variations on thisbasic approach include collection of

rainwater in gutters that drain to the collection vessel through downpipes

constructedforthispurpose,and/orthediversionofrainwaterfromthegutters

to containers for settling particulates before being conveyed to the storage

container for the domestic use. As the rooftop is the main catchment area, theamount and quality of rainwater collected depends on the area and type of

roofing material. Reasonably pure rainwater can be collected from roofs

constructed with galvanized corrugated iron, aluminium or asbestos cement

sheets, tiles and slates, although thatched roofs tied withbamboo gutters and

laid in proper slopes can produce almost the same amount of runoff less

expensively(Gould,1992).However,thebambooroofsareleastsuitablebecause

ofpossiblehealthhazards.Similarly,roofswithmetallicpaintorothercoatings

arenotrecommendedastheymayimparttastesorcolourtothecollectedwater.

Roof catchments should alsobe cleaned regularly to remove dust, leaves and

birddroppingstomaintainthequalityoftheproductwater.

2.3.2ConveyanceSubsystem

Conveyance systems are required to transfer the rainwater collected on the

rooftops to the storage tanks. This is usually accomplished by making

connectionstooneormoredownpipesconnectedtotherooftopgutters.When

selecting a conveyance system, consideration shouldbe given to the fact that,

when it firststarts torain,dirtanddebris from therooftopandgutterswillbe

washed into the downpipe. Thus, the relatively clean water will only beavailable some time later in the storm. There are several possible choices to

selectively collect clean water for the storage tanks. The most common is the

downpipeflap.Withthisflap,itispossibletodirectthefirstflushofwaterflow

throughthedownpipe,whilelaterrainfallisdivertedintoastoragetank.When

itstartstorain,theflapisleftintheclosedposition,directingwatertothedown

pipe, and, later, opened when relatively clean water canbe collected. A great


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disadvantageofusingthistypeofconveyancecontrolsystemisthenecessityto

observe the runoff quality and manually operate the flap. An alternative

approachwouldbetoautomatetheopeningoftheflapasdescribedbelow.

A funnelshaped insert is integrated into the downpipe system. Because the

upperedgeofthefunnelisnotindirectcontactwiththesidesofthedownpipe,

andasmallgapexistsbetweenthedownpipewallsandthefunnel,waterisfree

toflowbotharoundthefunnelandthroughthefunnel.Whenitfirststartstorain,

thevolumeofwaterpassingdownthepipeissmall,andthe*dirty*waterruns

downthewallsofthepipe,aroundthefunnelandisdischargedtothegroundas

isnormallythecasewithrainwaterguttering.However,astherainfallcontinues,

the volume of water increases and *clean* water fills the downpipe. At this

higher volume, the funnel collects the clean water and redirects it to a storage

tank.Thepipesusedforthecollectionofrainwater,whereverpossible,shouldbe

madeofplastic,PVCorotherinertsubstance,asthepHofrainwatercanbelow

(acidic)andcouldcausecorrosion,andmobilizationofmetals,inmetalpipes.Inorder tosafelyfillarainwaterstorage tank, it isnecessarytomakesurethat

excesswatercanoverflow,and thatblockages in thepipesordirt in thewater

doesnotcausedamageorcontaminationofthewatersupply.Thedesignofthe

funnelsystem,withthedrainpipebeinglargerthantherainwatertankfeedpipe,

helps to ensure that the watersupply is protectedby allowing excesswater to

bypass the storage tank. A modification of this design has a simple

overflow/bypass system. In this system, it is possible to fill the tank from a

municipaldrinkingwatersource,so thatevenduringaprolongeddrought the

tankcan

be

kept

full.

Care

should

be

taken,

however,

to

ensure

that

rainwater

doesnotenterthedrinkingwaterdistributionsystem

2.3.4StorageSubsystem

The storage tank (cistern) mustbe sized properly to ensure that the rainwater

potentialisoptimized.Cisternscanbelocatedaboveorbelowground.Thebest

materialsforcisternsincludeconcrete,steel,ferrocement,andfiberglass.When

ordering a cistern, specify whether the cistern willbe placed above orbelow

groundandifthecisternwillbeusedtostorepotablewater.(Fiberglasscisterns

areconstructeddifferentlytomeetthevariouscriteria.)(Sourcebook,HarvestedRainwater,1994)

Cisterncharacteristics

1 Acisternshouldbedurableandwatertight.

2 Asmoothcleaninteriorsurfaceisneeded.


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3 Jointsmustbesealedwithnontoxicwaterproofmaterial.

4 Manholesorrisersshouldhaveaminimumopeningof24inchesand

shouldextendatleast8inchesabovegradewithburiedcisterns.

5 Fittingsandcouplingsthatextendthroughthecisternwallshouldbecast

inplace.

6 Dissipatethepressurefromtheincomingwatertominimizethestirringof

anysettledsolidsinthebottomofthecistern.Thiscanbeaccomplishedin

aconcretecisternbyplacingconcreteblocks(cavitiesfacingupward)

surroundingthebaseoftheinletpipe.Theblockscanbe8x8x16blocks

withthepipeexitingoneinchabovethebottomofthecistern.Bafflesto

accomplishthesameresultcanbemadeaspartoffiberglasscisterns.This

isnotaconcernforcisternsthatalwayshavealargereserve.

7 Theuseoftwoormorecisternspermitsservicingoneoftheunitswithout

losingtheoperationofthesystem.

8 Haveafillpipeonthecisternforaddingpurchasedwaterasabackup.9 Haveacovertopreventmosquitobreedingandalgaegrowthfrom

contactwithsunlight.

Commonlyusedstoragesubsystemsareasfollows:

StorageTanks

Storage tanks for collecting rainwater harvested using guttering maybe either

above orbelow the ground. Precautions required in the use of storage tanks

include provision of an adequate enclosure to minimize contamination from

human, animal or other environmental contaminants, and a tight cover to

preventalgalgrowthand thebreedingofmosquitoes.Open containersare not

recommended for collecting water for drinking purposes. Various types of

rainwaterstoragefacilitiescanbefoundinpractice.Amongthemarecylindrical

Ferro cement tanks and mortarjars. The storage capacity needed shouldbe

calculatedtotakeintoconsiderationthelengthofanydryspells,theamountof

rainfall, and the per capita water consumption rate. In most of the Asian

countries, the winter months are dry, sometimes for weeks on end, and the

annualaveragerainfallcanoccurwithinjustafewdays.Insuchcircumstances,thestoragecapacityshouldbelargeenoughtocoverthedemandsoftwotothree

weeks.

RainfallWaterContainers


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externallyreinforcedwithpackagingstrap.Thepackagingstrapsalsoreducethe

amountofbricksneededtoconstructthetank.Thecapacityofthetankis

approximatelysixcubicmetres,withaninternaldiameterof2.0mandaheightof

2.0m.(DTU,1999)

TarpaulinLinedTank

ThisisusedinsouthernUganda.This6000litretankismadebylininga3mx2m

x1mdeepholewithastandardUNHCRbluetarpaulin(5mx4mripstopplastic

witheyeletsneartheedge).Thetarpaulinisheldupwithstringfromnailsdown

totheseeyelets.Asimplewall(wattleandmud,600mmhigh)isbuiltaroundthe

tank and roofed with slightly sloping corrugated iron sheets. The wall is lined

withplasticsackingtopreventmudfallingintothewater.Thewallroofjointis

sealedwithmud.Waterentersviaaholeintheroofsheeting(coveredbyafilter

clothandfedbyaslopingmetaldownpipe).Waterisextractedbydippingwith

a modified (cutaway) 10litrejerrycan via asmallwooden door in onewall

water isalwayswithinarmsreach.Someworkhasbeendoneondevelopinga

lowcost hand pump to extract water. There is normally no overflow and the

householderisexpectedtomoveasidethedownpipefeedingthestorewhenthe

waterlevelapproachesthetopofthetarpaulinlining

TheFerroCementJar

ThisjarhasbeenbuiltinareaslikeKyerainUganda.Itconsistsofabrickplinth,

aferrocementshellandafilterbasin.Thistechnologyhasbeenverysuccessful

inThailand.The ferrocement tankconsistsofa lightlyreinforcedconcretebase

on which is erected a circular vertical cylinder with a 10 mm steelbase. This

cylinderisfurtherwrappedintwolayersoflightwiremeshtoformtheframeof

thetank.Thistankhasthepotentialforsmall/largescaleproductionbyartisans,

very low maintenance; repairs can easilybe carried out, low cost, suitable for

many ground conditions and has good protection against mosquitoes. It

however requires a certain high level of skill. This has alsobeen practiced in

KyenjojoinUganda.(DTU,2000).


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BrickJars

Thejarconsistsofabrickoutersection;awaterproofinternalrenderandathin

mortarcoverwithafilterbasin.Ithaslowmanufacturetime, lowmaintenance,

repairseasilycarriedoutandconduciveformanygroundconditions.However,

thecostperlitrestorageishigherthanthePlasticTubeTank.

In his work in Western Uganda, Thomas (1995) observed that iron roof is the

mostcommoninthisareaduetothehighrainfall.


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TheThaijar

TheThaijarprogrammeisverymuchinpracticeatpresent.Therearetwotypes

of Thai rainwater harvesting systems. The individual householdjars and more

community oriented tanks. Both are surface structures withjars varying in its

capacity

from

1.2

to

2.0

m3

and

tanks

from

7.5m3

to

10m3

.

Both

these

structures

are widely seen in most rural areas in NE Thailand, though jars are more

commonly used. Ferrocementjars are also in use at a few urban households.

Privateenterprisesareintothemanufactureofrainwatercollectionjars.Almost

all people who collect rainwater use it exclusively for drinking and cooking.

People prefer rainwater to other water due to its taste. As stated earlier Thai

people in this part of the country hasbeen using rainwater traditionally for


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domestic use including drinking. As such, quality of collected water is not a

concernfor thesepeople.However,judgingby thestatusofcollectionsystems,

nothing good is say about the quality of water. Water quality tests conducted

during the early part of the programme under IDRC assistance, indicate

bacteriologicalcontaminationofrainjars.However,theresearchalsoshowsthat

contaminations fromothersourcesofwaterare fargreater than rainwaterjars.

For instance, traditionalearthenjarsandshallow ground water have indicated

higherconcentrationofcontaminationthanroofrunoff.(Ariyabandu,2001).

2.3.4FilteringSubsystem

Dirt, debris, and other materials from the roof surface may contaminate the

rainwater. Thebest strategy is to filter and screen out the contaminantsbefore

they enter the cistern. A leaf screen over the gutter and at the top of the

downspoutishelpful.Aprimarystrategyistorejectthefirstwashofwaterovertheroof.Thefirstrainfallwillcleanawayanycontaminantsand isachievedby

using a roof washer. The main function of the roof washer is to isolate and

reject the first water that has fallen on the roof after rain hasbegun and then

direct the rest of the water to the cistern. Ten gallons of rainfall per thousand

square feet of roof area is considered an acceptable amount for washing. Roof

washers are commercially available and afford reliability, durability, and

minimal maintenance to this function. Roof washing is not needed for water

used for irrigation purposes. However, pre filtering to keep out debris will

reducesedimentbuildup.Asandfiltercanalsobeused.(SourcebookHarvested

Rainwater,1994)

2.3.5Distribution

Removing the water from the cistern canbe achieved through gravity, if the

cistern is sufficiently high enough, or by pumping. Most cases will require

pumping the water into a pressure vessel similar to the method used to

withdrawandpressurizewaterfromawell(exceptasmallerpumpcanbeused

to pump from a cistern). A screened 1.25 inch foot valve inside the tank

connectedto

an

1.25

inch

outlet

from

the

cistern

approximately

one

foot

above

thebottom (toavoidanysettledparticles)willhelp maintain theprimeon the

pump.Afloatswitchshouldbeusedtoturnoffthepumpifthewaterlevelistoo

low.Anotheralternativeistheuseofafloatingfilterinsidethecisternconnected

toaflexiblewaterline.Thisapproachwithdrawsthewaterfromapproximately

onefootbelowthesurfacewhichisconsideredtobethemostclearwaterinany

bodyofwater.Thewaterthatwillbeusedforpotablepurposescanpassthrough


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an inline purification system or point of use water purification system. Other

uses for the water do not need additional purification. (Sourcebook Harvested

Rainwater,1994)

Rainwatersystemscanfurtherbeclassifiedbytheirreliability,whichgivesfour

typesofuserregimes:

Occasional water is stored for only a few days in a small container.

Suitable when there is a uniform rainfall pattern with very few days

withoutrainandthereisareliablealternativewatersourcenearby.

Intermittent in situations with one long rainy season when all water

demandsaremetbyrainwater;however,during thedryseasonwater is

collectedfrom

non

rainwater

sources.

Partial rainwater is used throughout the yearbut the harvest is not

sufficient for all domestic demands. For instance, rainwater is used for

drinking and cooking, while for other domestic uses (e.g.bathing and

laundry)waterfromothersourcesisused.

Full forthewholeyear,allwaterforalldomesticpurposesisrainwater.

In such cases, there is usually no alternative water source other than

rainwater,andtheavailablewatershouldbewellmanaged,withenough

storagetobridgethedryperiod.

The typeof user regimes tobe followed dependson many variables including

rainfallquantity,rainfallpattern(lengthoftherainyperiods,theintensityofthe

rains), available surface area, available or affordable storage capacity, daily

consumptionrate,numberofusers,costandaffordability,presenceofalternative

watersourcesandthewatermanagementstrategy.

2.4WaterQualityofRooftopRainwaterHarvestingSystems

Theraindropasitfallsfromthecloudissoft,andisamongthecleanestofwater

sources. Use of captured rainwater offers several advantages. Rainwater is

sodium free, abenefit for persons on restricted sodium diets. Irrigation withcaptured rainwater promotes healthy plant growth. Also, being soft water,

rainwater extends the life of appliances as it does not form scale or mineral

deposits.

Theenvironment,thecatchmentsurface,andthestoragetanksaffectthequality

ofharvestedrainwater.Thefallingraindropacquiresslightacidityasitdissolves


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carbon dioxide and nitrogen. Contaminants captured by the rain from the

catchment are of concern for those intending to use rainwater as their potable

water source. The catchment area may have dust, dirt, fecal matter frombirds

andsmallanimals,andplantdebrissuchasleavesandtwigs.

Water quality of rooftop rainwater harvesting systems is an issue of increased

interestparticularlyindevelopingcountrieswherethecollectedwaterisusedas

a source of drinking water. Studies reported from different parts of the world

reveal that the water quality is often suspected, especially in terms of its

microbiological quality. Among various factors that affect the water quality of

roofrunoff,roofmaterial,rainfallintensity,dryperiodprecedingarainfallevent

and proximity to pollution sources seem to determine the physicochemical

quality of the collected rainwater. As for microbiological quality, roof material

and any dry period could play a significant role in determining the quality. A

few studies, however, show that wellkept rainwater is a good quality source,usually within the WHO low risk category (Ariyananda & Mawatha 1999;

Coombes et al. 2000; Vasudevan et al. 2001). Poor collection and maintenance

practiceswillreducethequalityconsiderably.

Thisindicatestheneedforproperdesignandmaintenancestrategiestominimise

the contamination of potable roofcollected rainwater supplies. All studies

suggest that some form of treatment of the harvested rainwater is necessary

beforeitcanbeusedasasourceofdrinkingwater.

More studies are needed to assess the microbial risk associated with the

consumption

of

water

from

domestic

rainwater

harvesting

systems.

A

few

studies reported in the literature indicate that consumption of untreated

rainwater is a definite risk to the health of consumers (Crabtree et al. 1996;

Simmonsetal.1999,2001;Lye2002).Diseasesattributedto theconsumptionof

untreated rainwater includebacterial diarrhea,bacterial pneumonia,botulism,

protozoal diarrhea, and diarrheas from Giardia and Cryptosporidium. Most of

thestudiesreportedonthisaspectarefromdevelopedcountries.Thereisaneed

to assess the health implications of the use of rooftop rainwater harvesting

systems in developing countries, where the use of rainwater as a source of

drinking water isbecoming more widespread. There is also a need to develop

somesimpleandrapidfieldtestingmethodsforuse indevelopingcountriesto

indicatemicrobialcontaminationofdrinkingwater.TheH2Sstriptestbasedon

the production of H2Sby sulfate reducingbacteria appears tobe promising in

this regard (Vasudevan et al. 2001). A good correlation was observedbetween

theresultsofconventionalindicatorsofmicrobialpollutionandtheH2Sstriptest.

However,morestudiesareneeded tostandardisetheprocedure.Further,more

research is needed on how to improve the quality of rainwater collected from


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roof catchments through improvements in design features and maintenance

practices. The HACCP (hazard analysis and critical control point) approach,

introduced by the WHO in its latest edition of DrinkingWater Quality

Guidelines (WHO 2003) is suitable for design, construction, management and

operationofrooftoprainwaterharvestingsystems (Heijnen2001).HACCPalso

allows an assessment of risks related to the use of different roof surfaces and

fittingswouldhelpthepublichealthauthoritiestodeveloptheirownstrategies

toimprovethecollectedrainwaterquality.

Withminimaltreatmentandadequatecareof thesystem,however,rainfallcan

beusedaspotablewateraswellasforirrigation.Thecleanlinessoftheroofina

rainwater harvesting system most directly affects the quality of the captured

water.Thecleanertheroof,thelessstrainisplacedonthetreatmentequipment.

It is advisable that overhangingbranchesbe cut awayboth to avoid tree litter

andtodenyaccesstotheroofbyrodentsandlizards.

2.6SiteandRainwaterHarvestingSystemSelection

Itisimportantwhenchoosingarainwaterharvestingsystemtoconsidernotonly

the physical aspects of the projectbut the socio and economic requirements of

thecommunity it is toserve.Thesemay include the initialcosts, thequalityof

thewater,operationandmaintenancerequirementsofthetechnique.

The

most

important

parameters

to

consider

in

identifying

areas

suitable

for

rainwaterharvestingareasfollows:

2.6.1Rainfall

The knowledge of rainfall characteristics (intensityanddistribution) for a givenareaisoneoftheprerequisitesfordesigningarainwaterharvestingsystem.The

availability of rainfall data series in space and time and rainfall distribution is

important for determination of amount of rainwater that can be harvested.

Usefulrainfallfactorsfor thedesignofarain orfloodwaterharvestingsystem

include:

1. Number of days in which the rain exceeds the threshold rainfall of the

catchment,onaweeklyormonthlybasis,

2. Probabilityandoccurrence(inyears)forthemeanmonthlyrainfall,


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3. Probability and reoccurrence for the minimum and maximum monthly

rainfall,

4. Frequencydistributionofstormsofdifferentspecificintensities

2.6.2HydrologyandWaterResources

Thehydrologicalprocesses relevant to rainwaterharvestingpracticesare those

involved in the production, flow and storage of runoff from rainfall within a

particular project area. The rain falling on a particular catchment area canbe

effective (as direct runoff) or ineffective (as evaporation, deep percolation). Thequantityofrainfall thatproducesrunoff isagood indicatorofthesuitabilityof

theareaforrainwaterharvesting.

The other sources of water must be considered in designing of rainwater

harvesting system. For instance, ground water source may need rainwater to

rechargetheaquifersandthereforeharnessingallavailablerunoffwillaffectit.

2.6.3SocioEconomicandInfrastructureConditions

The socioeconomic conditions of a regionbeing considered for any rainwater

harvesting scheme are very important for planning, designing and

implementation.Thechancesforsuccessaremuchgreaterifresourceusersand

community groups are involved from early planning stage onwards. The

financialcapabilitiesoftheaveragefarmer,theculturalbehaviourtogetherwith

religiousbelief

of

the

people,

attitude

of

people

towards

the

introduction

of

new

technology,andtheroleofwomenandminoritiesinthecommunitiesarecrucial

issues.

ThisisparticularlyimportantinthearidandsemiaridregionsofAfricaandmay

helptoexplainthefailureofsomanyprojectsthatdidnottakeintoaccountthe

peoples priorities. For example in a West African study on water harvesting

(Tauer & Humborg 1992), the distance between the suitable areas and the

villages was regarded as an important criterion. It was assumed that farmers

werewillingtowalknotmorethan6kmfromtheirhomesiftheproposedwater

harvestingsystem isacceptable to them.Theexistingorplanned infrastructure

aswellas regionaldevelopmentplanshas tobeduly taken into accountwhen

planningarainwaterharvestingscheme(Siegert1994).

2.6.4EnvironmentalandEcologicalImpacts


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Dryareaecosystemsaregenerallyfragileandhavealimitedcapacitytoadjustto

change (Oweis et al. 1999). If the use of natural resources (land and water), is

suddenly changed by water harvesting, the environmental consequences are

often far greater than foreseen. Consideration shouldbe given to the possible

effectonnaturalwetlandsasonotherwaterusers,bothintermsofwaterquality

and quantity. New water harvesting systems may intercept runoff at the

upstreampartof thecatchment, thusdeprivingpotentialdownstreamusersof

theirshareoftheresources.Waterharvestingtechnologyshouldbeseenasone

componentofaregionalwatermanagement improvementproject.Components

of such integrated plans shouldbe the improvement of agronomic practices,

including the use of good plant material, plant protection measures and soil

fertilitymanagement(Oweisetal.1999).

2.6.5Costs

Thequantitiesofearth/stoneworkinvolvedinconstructiondirectlyaffectthecost

ofascheme.

2.7WaterBalanceandSystemSizing

Thebasicruleforsizinganyrainwaterharvestingsystem is that thevolumeof

waterthat

can

captured

and

stored

(the

supply)

must

equal

or

exceed

the

volume

ofwaterused(demand).Thevariablesofrainfallandwaterdemanddetermine

therelationshipbetweenrequiredcatchmentareaandstoragecapacity.Insome

cases, it maybe necessary to increase catchment surface areaby addition of a

barn or outbuilding to capture enough rainwater to meet demand. Cistern

capacitymustbesufficienttostoreenoughwatertoseethesystemanditsusers

throughthelongestexpectedintervalwithoutrain.

UsuallythemaincalculationwhendesigningaDRWHsystemwillbetosizethe

watertankcorrectlytogiveadequatestoragecapacity.Thestoragerequirement

willbedeterminedbyanumberofinterrelatedfactorswhichinclude;

Localrainfallandweatherpattern

Rooforothercollectionarea

Runoff coefficient (this variesbetween 0.5 and 0.9 depending on roofmaterialandslope)

Usernumberandconsumptionrates


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Rainfalldata is required,preferably foraperiod of at least10years. Themore

reliableandspecific thedata is for the location thebetter thedesignwillbe.A

figure for the average rainfall in a given area canbe found at offices of the

Department of Meteorological Services, Department of Agriculture or Water

Resources,atairportsandinthenationalatlasusedinschools.

Domesticwaterconsumptionanddemandvariessubstantiallybycountry.Socio

economic conditions and different uses of domestic water are among the

influencingfactors.Wherewaterisveryscarce,peoplemayuseaslittleasafew

litres per day. 20 lcd is a commonly accepted minimum. An estimate of the

amountofwaterrequiredforeconomicandproductiveusesshouldbeadded.In

general,roofrainwaterharvesting isonlyable toprovidesufficientwater fora

smallvegetableplot.

The style of rainwater will also play a part in determining the system

componentsandtheirsizes.Thereareanumberofdifferentmethodsforsizingsystemcomponents.Thesemethodsvary incomplexityandsophistication.The

choiceofmethodusedtodesignsystemcomponentswilldependlargelyonthe

following;

1. Thesizeandsophisticationofitscomponents

2. Theavailabilityofthe toolsrequiredforusingaparticularmethod(e.g.

Computers)

3. Theskillsandeducationlevelsofthepractitionerordesigner

Asthecostofdomesticrainwaterharvestingsystemdependsmainlyonthesize

ofthe

tank,

it

is

important

to

design

the

tank

to

ensure

optimum

performance

at

tolerablecost.

2.7.1SupplyCalculation

The volume of water (V) that canbe harvested over a roof area (supply) is

proportional to theamountofrain(R) fallingover theroofarea (A) isgivenby

theformula:

V(I)=R(mm)xA(m2)xCRwherebyCRistherunoffcoefficient.

TherunoffcoefficientCRforcorrugatedmetalsheetis0.70.9andfortilesis0.8

0.9.

2.7.2DemandCalculation

The first decision in rainwaterharvesting systemdesign is the intended use of

the water. If rainwater is intended to supply water during the then dry spells,


26/69


then the demand is calculated for the dry spells period. If the rainwater is

intendedtobethesolesourceofwaterforallindoorandoutdoordomesticend

uses,thenannualconsumptivedemandiscalculated.Waterdemandsdependon

theconsumptionratesandoccupancyofthebuilding.

DrySpellsDemand=Consumptionper capitaperday,CxNumberofpeople

perhousehold,nxLongestaveragedryperiod,t

Annual Consumption Demand, D = Consumption per capita per day, C x

Numberofpeopleperhousehold,nx365

2.7.3StorageCapacityCalculation

Rainfalloccursseasonally,requiringastoragecapacitysufficient tostorewater

collectedduringrainytimestolastthroughthedryspells.

BelowoutlinethreedifferentmethodsforsizingRWHsystemcomponents.

Method1 demandsideapproach

Averysimplemethodistocalculatethelargeststoragerequirementbasedon

theconsumptionratesandoccupancyofthebuilding.

Typicaldataneededtoestimatethetanksizeare;

Consumptionpercapitaperday,C

Numberofpeopleperhousehold,n

Longestaveragedryperiod,t

Annualconsumption,D=Cxnx365=Alitres

Storagerequirement,T=(Annualconsumption,Dxdryperiod,t)/365=Blitres

Thissimplemethodassumessufficientrainfallandcatchmentareathatis

adequate,andisthereforeonlyapplicableinareaswherethisisthesituation.Itisamethodforacquiringroughestimatesoftanksize.

Anothersimple methodof roughly estimatingstoragecapacitypopularamong

professional installers is tosize thestoragecapacity tomeetquarterlydemand.

Thesystemissizedtomeetestimateddemandforathreemonthperiodwithout


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rain.Annualdemandisdividedbyfourtoyieldnecessarystoragecapacityusing

thisapproach.

Method2supplysideapproach

Rainwatersupplydependsontheannualrainfall,theroofsurfaceareaandthe

runoffcoefficient.

Supply=AnnualRainfall(mm/year)xarea(m2)xRunoffcoefficient

To ensure a yearround water supply, the catchment area and the storage

capacity mustbe sized to meet water demand through the longest expected

intervalwithoutrain.Inthisapproach,thestoragecapacityisdeterminedbased

onthewaterthatcanbeharvested.

Method3computermodel

SpecialsoftwarefortanksizingcalledSIMTANKAhasbeendeveloped(www.

geocities.com/Rainforest/canopy/4805). It requires at least 15 years of monthly

rainfallrecordsfortheplaceofwhichtherainfallharvestingsystemislocated.If

that isnot available then thatof the nearest place thathas thesamepatternof

rainfall canbe used.The included utility rain recorder is used forentering the

rainfalldata.Dailyconsumptionperpersonisalsoenteredandthenthesoftware

will calculate optimum storage size or catchment size depending on the

requirementoftheuser.

2.8PotentialEffectsandImpactsTakingaLivelihoodsBasedApproach

The impacts of rooftop rainwater harvesting will be greatest where it is

implemented as part of wider strategies that take as a starting point peoples

overall livelihood strategies. In this context, water should be seen as a key

productiveaswellasdomesticresource,withdifferentusesbeingmadeofitby

men and women. The flexibility of rainwater harvesting gives room forinnovation. For example, there can arise an interrelation of variety of both

economicandsocialactivitiesthatcanimprovelivingstandards.Themain idea

starts from intercepting rainwater as a hydrological cycle component and

diverting it to food/feed production including processing, marketing and

compost sourcing/recycling. This is a holistic approach of interactions of many

profitable activities originating from a controlled water source. From one


28/69


rainwater harvesting storage structure can arise a myriad of interrelated

activities including kitchen gardens, poultry keeping, zero grazing, biogas

digester installations, manure harvesting, drip irrigation for horticultural crops

productionandfishfarmingamongothereconomicactivities.Alltheseactivities

have a projection on increased income generation, improved nutrition status,

improved sanitation and personal hygiene, creation of onfarm employment

leadingtopovertyreductionandconservationoftheenvironment.(Gould,1999)

The impactsofroofwaterharvestingtakinga livelihoodapproachwouldbeas

follows;

2.8.1ReductionofBurdensofthePoor

Women and female children spend more than 200 million hours each day to

collectwaterfromdistant,oftenpollutedsources.Themostimportantimpactinterms of women and the poor is the reduction in time spent collecting water,

whichcanbeasmuchasseveralhoursperday.Thistimethenbecomesavailable

for other purposes, both productive and social; more time to spend with

children,friends,etc.

2.8.2HealthImpacts

Rainwater is often used for drinking and cooking and so it is vital that the

highest

possible

standards

are

met.

Rainwater,

unfortunately,

often

does

not

meettheWorldHealthOrganisation(WHO)waterqualityguidelines.Thisdoes

notmeanthatthewaterisunsafetodrink.GouldandNissenPeterson(1999),in

their recentbook, point out that the Australian government have given the all

clearfortheconsumptionofrainwaterprovidedtherainwaterisclear,haslittle

taste orsmell,and is fromawellmaintainedsystem. It hasbeen found thata

favourable user perception of rainwater quality (not necessarily perfect water

quality) makes an enormous difference to the acceptance of RWH as a water

supplyoption.

Generally,thechemicalqualityofrainwaterwillfallwithintheWHOguidelines

and rarely presents problems. There are two main issues when looking at the

qualityandhealthaspectsofDRWH:

Firstly, there is the issue of bacteriologicalwater quality. Rainwater canbecomecontaminatedbyfaecesenteringthetankfromthecatchmentarea.It isadvised

that the catchment surface alwaysbe kept clean. Rainwater tanks shouldbe

designedtoprotectthewaterfromcontaminationbyleaves,dust,insects,vermin,

andotherindustrialoragriculturalpollutants.Tanksshouldbesitedawayfrom


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trees,withgoodfittinglidsandkeptingoodcondition.Incomingwatershould

befilteredorscreened,orallowedtosettletotakeoutforeignmatter. Waterthat

isrelativelycleanonentrytothetankwillusuallyimproveinqualityifallowed

tositforsometimeinsidethetank.Bacteriaenteringthetankwilldieoffrapidly

ifthewaterisrelativelyclean.Algaewillgrowinsideatankifsufficientsunlight

is available for photosynthesis. Keeping a tank dark and sited in a shady spot

will prevent algae growth and also keep the water cool. The dirty first flush

water must always be diverted away from the storage tank. The area

surrounding a RWH shouldbe kept in good sanitary condition, fenced off to

preventanimalsfoulingtheareaorchildrenplayingaroundthetank.Anypools

ofwatergatheringaround the tankshouldbedrainedand filled.Gouldpoints

out that in a study carried out in northeast Thailand 90 per cent of inhouse

storage jars were contaminated whilst only 40% of the RWH jars were

contaminated.Thissuggestssecondarycontamination(throughpoorhygiene)is

amajorcauseofconcern.Secondly,thereisaneedtopreventinsectvectorsfrombreedinginsidethetank.

In areas where malaria is present, providing water tanks without any care for

preventing insectbreeding, can cause more problems than it solves. All tanks

shouldbesealedtopreventinsectsfromentering.Mosquitoproofscreensshould

be fitted to all openings. Some practitioners recommend the use of 1 to 2

teaspoons of household kerosene in a tank of water which provides a film to

preventmosquitoessettlingonthewater.

Thereareseveralsimplemethodsoftreatmentforwaterbeforedrinking.

1. Boilingwater

will

kill

any

harmful

bacteria

which

may

be

present

2. Addingchlorineintherightquantity(35mlofsodiumhypochloriteper

1000litresofwater)willdisinfectthewater

3. Slowsandfiltrationwillremoveanyharmfulorganismswhencarriedout

properly

4. ArecentlydevelopedtechniquecalledSODIS(SOlarDISinfection)utilises

plasticbottleswhicharefilledwithwaterandplacedinthesunforone

fullday.Thebackofthebottleispaintedblack

However, rainwater is usually a considerable improvement over unprotected

traditional sources and stored rainwater maintains a good water quality

providedthetankiswellmaintained.

Directandindirecthealthimpactsinclude:

1. Waterrelatedillnessesarereducedbecauseoftheuseofcleanerandsafer

rainwater (although householdbased treatment is recommended),

particularlycompared towater fromsurfacesources.This results in less

sickdays,increasedeconomicactivities,andsavingsinmedicalexpenses.


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2. Malnutritionmayreduceasrainwaterusedforvegetableandothercrop

growingcontributestoanimproveddiet.

3. Improvedsanitationandhygieneresultingfrom increasedavailabilityof

watercanalsoaddtoimprovedhealth.

4. Reducedtransportationofheavyloadsoverlongdistancesfromanearly

ageleadstoreducedbackproblemsandgrowthreduction

5. Increasedincomestreamsfromproductiveusesofadditionalwatercanin

turn lead improved nutritional status and a reduction in communicable

diseasesduetoimprovedhomeenvironmentalconditions(betterhousing,

ventilationetc.)

2.8.3EconomicImpacts

Direct economic impacts will come almost entirely from the use of water for

economic activities. Apart from the environmental gains, there is an economicadvantage to the harvesting and use of rainwater, most notably in the

commercialsectoras theserviceproviderscontinue to increasecharges.Farms,

horticulturalestablishments,publicbuildingssuchasschoolsandvisitorcentres,

publichousing,petrolstations (usingwaterforvehiclewashing)couldallgain

an economic advantageby using harvested rainwater and stop using treated

waterfornondrinkableuses.

This may lead to significant poverty alleviation leading to improved living

conditionsasmanyRWHinitiativeshaveshown.

1. Productive

use

of

rainwater

for

vegetable

gardening

(small

scale

irrigation),

2. Productive use of rainwater for homebased economic activities such as

beerbrewing,brickmaking,oilmakingetcand

3. Income generating activities may alsobe the result of the utilization of

timesavedincollectionofdomesticwater.

2.8.4PovertyAlleviation

Direct and indirect capacitybuilding, (skill development, knowledgebuilding,

access to information), reduction of vulnerability, strengthening of social and

physicalinfrastructure,allhelptoalleviatepoverty.Duringmobilization(e.g.in

PRAs etc.) issues such as injustice, isolation from existing institutions and

suppliesareanalyzedandcanbespecificallyaddressed.

Childrenandparticularlyyounggirlsmaybedeprivedofeducationduetothe

needtoassisttheirmothersincollectingwaterfromfarawaysources.Thetime


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saving in collection from the close to home source will allow them to attend

school.

2.8.5EnvironmentalBenefits

Rainwaterharvestingpromotesindependenceandselfsufficiencyandalsohelp

to develop an appreciation for this precious and finite resource. This activity

conserves water and also energy input to treat and pump water over a vast

serviceareaforacentralisedwatersystem.Asidefromconservingwateruse, it

alsominimises localerosionand floodingdue torunoff from imperviousareas

suchaspavementandroofsanddecreasesstormwaterrunoffwhichpicksup

contaminantsanddegradesdrains,streams,riversandseas.Since58%ofrainfall

inMalaysiaendsupassurfacerunoff,there isastrongcasetoemploysystems

suchasRWHStoputanendtosuchwastedresources.

2.8.6DomesticandIndustrialBenefits

The exceptional quality of rainwater has made it a viable water resource

supplement.Rainwaterqualityoftenexceedsthatofgroundorsurfacewater,as

it does not come into contact with soil, dissolving salts and minerals in the

process.It

is

not

subject

to

pollutants

found

in

rivers.

Rainwater

has

hardness

approachingzero therebyreducingsignificantly thequantityofdetergentsand

soapsneededforcleaning,ascomparedtotypicalpipedwater.Thereisvirtually

nosoapscumandhardnessdepositsthuseliminatetheneedforawatersoftener,

whichisexpensiveforwellwatersystems.Waterheatersandpipeswillbefree

ofdepositscausedbyhardwaterandthiscanprolongtheirservicelifetime.

2.9PlanningandManagementofRainwaterHarvestingSystem

Domesticrainwaterharvestingneedstobeseenasonlypartofasystemtomeet

theoverallwater requirementsofahouseholdorcommunity.Projectplanning

must take a peoplecentred approach taking socioeconomic, cultural,

institutional, and gender issues into account, as well as peoples perceptions,

preferencesandabilities.FactorsforsuccessinDRWHare:

1. projectstartssmallandgrowsslowlytoallowfortestingandmodification

ofdesignandimplementationstrategy;


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2. demandforwaterisclearlyexpressed;

3. fullinvolvementofbothsexesinallprojectstages;and

4. substantialcontributionsfromthepeopleinideas,fundsandlabour.

Inanumberofcountries(e.g.Kenya,Fiji)womensgroupshavebeenvery

successfulinfinancingandbuildingtheirownRWHtanks.Managementbyindividualhouseholdsismostsuccessful.Thisisbecausethe

user(oftenawoman)operatesandcontrolsthesystem,isresponsibleforits

maintenance,managestheuseofwater(minimummisuse),andappreciatesthe

convenienceofwaternexttoherhome.

Rainwaterismanagedinanumberofways.Themainmanagementstrategiesare

listedbelow.

MaximumSecurity

Thewaterfromthetankisnotutilizeduntilallthepossiblewatersourcesare

completelydepleted.Inthiscase,intherainyseasonafterthetankhasbeenfilled,

itislockedup.Thishasadisadvantageofnotmaximizingthewaterfromthe

roofs,thusthetankislefttooverflow.

MaximumCapture

Thetankisusedasawatersourcethroughouttherainyseason.Itkeepsfillingas

thestoredwaterisbeingutilized.However,thereisatendencyofreducingthe

dailyconsumptionasthedryseasonsetsin.


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CHAPTERTHREE

CASESTUDYOFGHANA

General

Background

GhanaliesinthecenteroftheWestAfricancoast,sharesborderswiththethree

Frenchspeaking nations of Cte dIvoire to the west, Togo to the east, and

BurkinaFaso(Burkina,formerlyUpperVolta)tothenorth.Tothesoutharethe

Gulf of Guinea and the Atlantic Ocean. With a total area of 238,533 square

kilometers, Ghana is about the size of Britain. Its southernmost coast at Cape

ThreePointsis430 northoftheequator.Fromhere,thecountryextendsinland

forsome670kilometerstoabout11north.Thedistanceacrossthewidestpart,

between longitude 1 12 east and longitude 3 15 west, measures about 560

kilometers. The Greenwich Meridian, which passes through London, also

traversestheeasternpartofGhanaatTema

The climate of Ghana is tropical, but temperatures vary with season and

elevation. Except in the north two rainy seasons occur, from April toJuly and

fromSeptembertoNovember.Inthenorth,therainyseasonbeginsinApriland

lastsuntilSeptember.Annualrainfallrangesfromabout1,100mm(about43in)

inthenorthtoabout2,100mm(about83 in) inthesoutheast.Theharmattan,a

drydesert wind,blows from the northeast from December toMarch, lowering

thehumidityandcreatinghotdaysandcoolnightsinthenorth.Inthesouththe

effects of the harmattan are felt in January. In most areas the highesttemperaturesoccurinMarch,thelowestinAugust.Ghanaisalowlandcountry,

exceptforarangeofhillsontheeasternborder.Thesandycoastlineisbackedby

acoastalplainthatiscrossedbyseveralriversandstreams,generallynavigable

onlybycanoe. In thewest,heavilyforestedhillsandmanystreamsandrivers

breaktheterrain.Tothenorthliesanundulatingsavannacountrythatisdrained

by the Black and White Volta rivers, whichjoin to form the Volta, which then

flows south to the sea through a narrow gap in the hills. Much of the natural

vegetation of Ghana hasbeen destroyedby land clearing for agriculture,but

such trees as the giant silk cotton, African mahogany, and cedar are still

prevalentinthetropicalforestzoneofthesouth.Thenortherntwothirdsofthe

country iscoveredbysavannaagrasslandwithscattered trees.Animal lifehas

alsobeendepleted,especiallyinthesouth,butitremainsrelativelydiverseand

includes leopard, hyena, buffalo, elephant, wildhog, antelope, and monkey.

Manyspeciesofreptilesarefound,includingthecobra,python,puffadder,and

horned adder. Agriculture is Ghanas most important economic sector,


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employing more than half the population on a formal and informalbasis and

accountingforalmosthalfofGDPandexportearnings.Thecountryproducesa

varietyofcropsinvariousclimaticzoneswhichrangefromdrysavannatowet

forest and which run in eastwestbands across the country. Agricultural crops,

includingyams,grains,cocoa,oilpalms,kolanuts,andtimber,formthebaseof

Ghanaseconomy.

BackgroundonNorthernRegion

Locationandsize

TheNorthernRegion,whichoccupiesanareaofabout70,383squarekilometres,

isthelargestregioninGhanaintermsoflandarea.Itsharesboundarieswiththe

UpperEastandtheUpperWestRegionstothenorth,theBrongAhafoandthe

Volta Regions to the south, and two neighbouring countries, the Republic of

Togo to the east, and La Cote d Ivoire to the west. The region is divided into

eighteen(18)districts.TheseareBole,BunkpuruguYungoo,CentralGonja,EastGonja, East Mamprusi, Gushiegu, Nanumba North, Nanumba South, Saboba/

Chereponi, Saveugu/ Nanton, SawlaTunaKalba, Temale Metropolitan,

Tolon/Gumbungu,WestGonja,WestMamprusi,YendiandZabzugu.

The land is mostly low lying except in the northeastern corner with the

Gambagaescarpmentandalong thewesterncorridor.Theregion isdrainedby

theBlackandwhiteVoltaandtheirtributaries,RiversNasia,Daka,etc.

Climateandvegetation

Theclimateoftheregionisrelativelydry,withasinglerainyseasonthatbegins

in May and ends in October. The amount of rainfall recorded annually varies

between750mmand1050mm.ThedryseasonstartsinNovemberandendsin

March/Aprilwithmaximumtemperaturesoccurringtowardstheendofthedry

season(MarchApril)andminimumtemperaturesinDecemberandJanuary.The

harmattanwinds,whichoccurduringthemonthsofDecembertoearlyFebruary,

have considerable effect on the temperatures in the region, which may vary

between 14C at night and 40C during the day. Humidity, however, which is

very low, mitigates the effect of the daytime heat. The rather harsh climaticcondition makes the cerebrospinal meningitis thrive, almost too endemic

proportions, and adversely affects economic activity in the region. The region

also falls in the onchocerciasis zone,but even though the disease is currently

undercontrol,thevastareaisstillunderpopulatedandundercultivated.


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Themainvegetationisclassifiedasvastareasofgrassland,interspersedwiththe

guineasavannahwoodland,characterisedbydroughtresistanttreessuchasthe

acacia,baobab,sheanut,dawadawa,mango,neem.

Demographiccharacteristics

The population of the region is 1,820,806, representing 9.6 per cent of the

countryspopulation.This translates intoagrowthrateof2.8percentover the

1984populationof1,162,645.Thisrateofgrowthismuchlowerthanthatof3.4

percentrecordedbetween1970and1984.

Economicactivities

Agriculture,hunting,andforestryarethemaineconomicactivitiesintheregion.

Together,

they

account

for

the

employment

of

71.2

per

cent

of

the

economically

active population, aged 15 years and older. Less than a tenth (7.0%) of the

economicallyactivepeopleintheregionareunemployed.

Mainsourceofdrinkingwater

Thecommonestsourcesofdrinkingwaterintheregionaretherain,spring,river

and stream (27.2%). About a fifth of households (19.6%) use dugouts for the

collectionofrainwater,followedbypipebornewaterintheformofastandpipe,

either insideoroutside thehouse (22.4%)andborehole (17.0%).Othersources,

constituting mainly tanker supply, represent only about 1.0 per cent ofhouseholdwatersources.Thismeansthatonly39.4percentofhouseholdshave

access to potable water (pipeborne plus borehole); this has implications for

water borne diseases for the region. At the district level, the proportion of

householdswithpipedwatervariesfrom0.9percentinEastMamprusiDistrict,

to78.9percentinTamalemunicipality.Inmostofthedistricts,themainsources

of water are wells, dugouts or rainwater/rain/river/stream. The dependence on

these sources of water has major implications for the health of the population.

Contaminationsduringtheprocessofcollectionmayaggravatetheincidenceof

diarrhoea and other waterborne diseases. The use of the tanker supply, an

important source of household water, is only prevalent in Tamale where it

accountsforabout4.0percentofthewatersupplyofhouseholds.

1.BackgroundonEastGonjaDistrict(NorthernRegion)


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The East Gonja District is the second largest district in the Northern region. It

sharesborders with the Yendi and Tamale Districts to the north, West Gonja

District to the West, Nanumba district of BrongAhafo and Volta Regions

respectivelytothesouth.Itoccupiesanareaofabout10,787squarekilometers.

TopologyandDrainage:

The topography of the district is typical of the Northern Region, generally flat

withfewundulatingsurfaces.Nowheredoesthelandriseupto200metres.The

district isunderlainby theVoltariansedimentary formationwith lowpotential

formineralformationsandpoorwaterretention.

The area receives annual precipitation averaging 1,050mm, considered enough

forsinglefarmingseason.Temperaturesareusuallyhigh,averaging300C. The

main

drainage

system

in

the

district

is

made

up

of

the

Volta

and

some

of

its

majortributariesincludingtheWhiteVolta,theDakerandOtiRivers.Thereisa

good flow of water which is collected and stored in the Volta Lake. Potential

existsforirrigationandsmalldamsites. Thenaturalvegetationinthedistrictis

GuineaSavannahWoodland,whichconsistsof trees thataredroughtresistant.

Mostof these trees are ofeconomic value.Notable amongst them are the shea

and dawadawa trees. Compared to the rest of the Northern Region, the tree

cover is dense although intense harvesting for fuel wood is fast reducing the

naturalflora.

Attheextremesoutheast,thevegetationisdenseandsemideciduoustreessuchas oil palm trees, raffia palms and others canbe found. There are three major

groups of soils in the district: Alluvial Soils, Ground water Laterites and

SavannahOchrosols.

EconomicActivities

EastGonjadistrictseconomy ispurelyrural,dominatedbyagriculture,which,

includefishingandforestry,accountsfor76%oftotalemployment.Agriculture

intheEastGonjaDistrictisdominatedbycropfarming,whichprovidesthemain

farm income. The district is a major producer of maize, rice cassava, yam and

sorghum.

Livestock(cattle,goats,sheepandpigs)arekeptbutnotaspartofmixedfarming

system. Inland fishing is a major source of activity in the district particularly


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alongtheVoltaLakeanditstributaries.Manufacturingaccountsforabout6.5%

ofthelabourforce.

Pitobrewingdominatesintheareaoffoodandbeverageprocessing;andtextile

manufacturing, involvingsmallscale informalsectorartisans is theothermajor

manufacturingactivity.Commerceemploysabout15%ofthetotallabourforce,

mostly in theareaofretail trading.Thereare14markets located in thedistrict,

where,inthemainagriculturalproduceissold.

BackgroundonWestMamprusiDistrict(NorthernRegion)

TheWestMamprusiDistrictisoneof45newdistrictscreatedin1988underthe

Government of Ghanas decentralization and local government reform policy.

Carved out of the old Gambaga District in the Northern Region. The district

capital is Walewale, which lies on the TamaleBolgatanga trunk road,

approximately68milesawayfromTamale.Thedistrictisborderedtothenorth

byBuilsa,KassenaNankanaandBolgatangadistricts,intheUpperEastRegion;

to the south west by Gonja, TolonKumbungu and Savelugu district in the

NorthernRegion;tothewestbytheSissalaandWadistricts;andtotheeastby

EastMamprusiandGushieguKaragaDistricts.

LocationandSize

TheWestMamprusiDistricthasanareaofabout5,013squarekilometers.

TopologyandDrainage

MajorriversthatdrainthedistrictaretheKulpawn,WhiteVoltaandNasia.

ClimateandVegetation

ThearealiesintheGuineaSavannahzone.Consequently,thevegetation

comprisesshorttress,grassesandshrubs.

EconomicActivities


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Agricultureisthemajoreconomicactivityinthedistrict.Cropsproducedinthe

district are maize, rice, millet, sorghum, groundnuts,beans, yams, cotton and

soyabean. Livestock production is another activity in the district with a lot of

economicpotential.Thefairlyflatlandcoupledwiththeavailabilityofgrassesin

mostpartsofthedistrictprovidesanidealenvironmentforlivestockandpoultry

rearing.Animals reared includecattle,sheepgoats,pigandbirds. Importantly,

there is littleorno incidenceof tsetsefly in most areasof thedistrict,a further

advantageforlivestockfarmers.

Thepresenceoflargewaterbodiesalsocreatesalotofpotentialforirrigationin

the district in the dry season for production of crops. Tomatoes, pepper, soya

beans, onions, vegetables and tobacco among others are cultivated along the

banksofthemainriverdrainingthedistrict,theWhiteVolta.Thedevelopment

of irrigation further from the rivers would greatly enhance agricultural

productivityforlargescalefarmers.

3.BackgroundonNanumbaDistrict(NorthernRegion)

NanumbaNorthDistrictislocatedattheeasternpartoftheNorthernRegionof

Ghana.ThedistrictsharesboundarieswithEastGonjaDistrict to thewestand

southwest,andYendiDistricttothenorth.Totheeast,itsharesboundarieswith

Zabzugu/TataliDistrictandtheRepublicofTogo,andtothesoutheastwiththe

VoltaRegion.ThedistrictcapitalisBimbilla.

LocationandSizeThedistricthasareaofabout3,220squarekilometers.

TopologyandDrainage

ThemaindrainagefeaturesofthedistrictareRiverOtiandDakar.TheOtiRiver

hasabout85kmofitsstretchmeanderingfromnorthtosouththroughthe

district,whiletheDakarRiverspans145kmofthewesternboundarywithEast

GonjaDistrict.OtherdrainagefeaturesincludeKumboandKumarstreams,

dams

and

dug

outs,

and

Jual

Gorge

designated

as

a

hydroelectric

site

on

the

Oti

River.


ThedistrictliesintheTropicalContinentalClimateZonewiththemiddaysun

alwaysoverhead.Asaresult,temperaturesarefairlyhighrangingfrom29


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degreescelsiusto41degresscelsius.ItsvegetationtypeistheGuineaSavannah

withtallgrassinterspersedwithdroughtandfireresistanttrees.Treespecies

foundarethedawadawa,sheanut,baobabandotherfire resistanttrees.

GeologyandSoil

SoiltypesaretheSavannahOchrosols.SavannahOchrosolsareofalluvial

colluvialoriginfoundmainlyalongmajorriversanddrainagecoursesandare

locatedmidsouththroughtothenorth.Theyaremediumtexturedmaterial,

moderatelywelldrainedsoilssuitedforawiderangeofcropssuchascereals,

rootsandtubers,andlegumes.

ThesavannahOchrosolsarewelldrainedsoilswiththesurfacehavingloamy

sandorsandtexturedmaterialwithgoodwaterretention.Inthedistrict,these

soilsare

located

to

the

east

of

the

Oti

River

and

the

south

west

through

to

the

north.Groundwaterlateritesareshallowsandyorloamysoilscomposedofrock

fragmentsfoundonthesummitsofuplandareas.Theyaresuitableforforestry

andconservationprogrammes.Thedistrictsoilsarecharacteristicallyheavyand

darkcoloured.

EconomicActivities

Agricultureisthemajoreconomicactivityinthedistrict.Thesoilsaresuitablefor

thecultivationofcerealssuchasrice,sorghum,milletandmaize.Theyarealso

wellsuited for legumes,suchascowpea,soyabeans,groundnuts,andbambarabeans.

The women are involved in the production of oils from groundnut, soya and

sheanuts.

4.BackgroundonYendiDistrict(NorthernRegion)

The Yendi District cut through by the Greenwich Meridian, which passes

through a number of settlements in the district. The district sharesboundaries

withsevenotherdistrict;totheeast,withSaboba/ChereponiandZabzugu/Tatale,to the south, with Nanumba and East Gonja, to the west, with Tamale and

Saveluguandtothenorth,withGushiegu/karagadistricts.Ithasanareaofabout

5,350squarekilometres

EconomicActivities


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MajorityofthepeopleareemployedintheAgriculturalsector.Themajorcrops

grown in thedistrictaremaize,rice,sorghum,millet,cassava,yam,groundnut

andbeans,allofwhichareoutstandinglyproductiveintheareaInstructively,the

MinistryofFoodandAgricultureestimatesthattheyieldsperhectareforthese

crops in Yendi District are all higher than the averages for the whole of the

NorthernRegion.

BackgroundonUpperEastRegion

Physicalfeatures

Upper East is located in the northeastern corner of the country between

longitude00and10Westandlatitudes10030Nand110N.Itisborderedtothe

northbyBurkinaFaso, theeastby theRepublicofTogo, thewestbySissala in

UpperWest

and

the

south

by

West

Mamprusi

in

Northern

Region.

The

land

is

relatively flat with a few hills to the East and southeast. The total land area is

about8,842sqkm,whichtranslatesinto2.7percentofthetotallandareaofthe

country.

Upper East region has eight districts namely: Bawku Municipal, Bawku West,

Bolgatanga Municipal, Bongo, Builsa, GaruTempane, Kassena/Nankana and

Nabdam.

SoilandDrainage

The regions soil is upland soil mainly developed from granite rocks. It is

shallow and low in soil fertility, weak with low organic matter content, and

predominantly coarse textured. Erosion is a problem. Valley areas have soils

rangingfromsandycandyloamstosaltyclays.Theyhavehighernaturalfertility

butaremoredifficulttotillandarepronetoseasonalwaterloggingandfloods.

Drainage is mainlyby the White and Red Volta and Sissili Rivers (Regional

CoordinatingUnit,2003).


The climate is characterized by one rainy season from May/June to

September/October.Themeanannualrainfallduringthisperiod isbetween800

mm and 1.100 mm. The rainfall is erratic spatially and in duration. There is a

longspellofdryseasonfromNovembertomidFebruary,characterizedbycold,

dryanddustyharmattanwinds.Temperaturesduringthisperiodcanbeaslow


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as14degreescentigradeatnight,butcangotomorethan35degreescentigrade

duringthedaytime.

Humidity however, very low making the daytime high temperature less

uncomfortable.TheregionisentirelywithintheMeningitisBeltofAfrica.Itis

also within the onchocerciasis zone,but with the control of the disease, large

areas of previously abandoned farmlands have been declared suitable for

settlementandfarming.

Thenaturalvegetation isthatofthesavannahwoodlandcharacterisedbyshort

scattered droughtresistant trees and grass that gets burnt by bushfire or

scorched by the sun during the long dry season. Human interference with

ecology issignificant,resulting innearsemiaridconditions.Themostcommon

economictreesarethesheanut,dawadawa,boababandacacia.

WaterSupply

About 51 per cent of the regions population have access to potable drinking

water. Ghana Water Company Limited (GWCL) supplies pipeborn water to

Bolgatanga,Chuchuliga,Zebilla,Bawku,Sandema,Navrongo,BongoandPaga.

Almost two thousand (1,627) hand pumps (boreholes) and a number of hand

dug wells serve a majority of the rural populations. While water treated for

consumptioninBolgatangaisfromtheVeaDam,thepipebornwatersystemsin

theothertownships

Housing

The majority of the people live in hutsbuilt of mud and roofed with straw or

zinc.Themainfeaturesof thepredominantly traditionalarchitectureareround

hutswithflatroofsandsmallwindowswithpoorventilation.

EconomicActivities

Agriculture,huntingandforestryarethemaineconomicactivitiesintheregion.

About eighty per cent of the economically active population engages in


42/69


agriculture.Themainproducesaremillet,guineacorn,maize,groundnut,beans,

sorghumanddryseasontomatoesandonions.

Livestock and poultry production are also important. There are two main

irrigation projects, the VeaProject inBolgatangacovering850 hectaresand the

Tono Project in Navrongo covering 2,490 hectares. Altogether, they provide

employmenttoabout6,000smallscalefarmers.Otherwaterretainingstructures

(damsanddugouts)providewaterforbothdomesticandagriculturalpurposes.

Theregionisalsoknownforitshandicraftsandalocallybrewedbeerknownas

Pito.

1.BackgroundonBawkuMunicipal/EastDistrict(UpperEastRegion)

The Bawku Municipal sharesboundaries with the Republic of Burkina Faso to

thenorth,

Togo

to

the

north

east,

East

Mamprusi

District

of

the

Northern

Region

tothesouthandBawkuWestDistricttothewest.

Locationandsize

Thedistricthasanareaofabout2067squarekilometres

TopologyandDrainage:

Generally,thedistricthasalowtopographywiththepopularZawse/Yarigungu

AgolandKugriHillsrangerisingbetween1000and2000feet.TheWhiteVolta

RiveranditstributariesrunintothedistrictfromBurkinaFasoandTogo.


Theclimate is tropicalandthevegetation issavannah,characterizedwithshort

trees,mostlynim,sheaandmahogany.

GeologyandSoil

Thesoilsaresandyclayloamsandalluvialsandylomswithinterspersedgravel

androckswhicharecommonlyusedforbuildinghomesandconstructionwork

onroads.

EconomicActivities

Agricultureisthemajoreconomicactivityinthedistrict.Thestaplefoodstuffsof

theBawkuEastDistrictincludemillet,rice,redandwhitesorghum,groundnut,


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ginea corn, maize and Bambara Beans. About 90% of the food produced at

subsistence level is consumed locally while onions and malts are transported

down south for sale. Cotton, sheanuts and sweet potatoes are the cash crops

producedintheDistrict.Livestockproductionisalsoontheincrease.

TheBawkuEastDistrictisnotedfortheproductionofhighqualitysmocks,shea

butter,groundnutoil,earthweareproductsanddawadawa.Womenarethemain

producers of these items and they are financed through loans from the

EmploymentandIncomeGenerationFundoftheDsitrictAssembly,theBawku

East Women Development Association, ACTION AID, (a British NGO),

Agricultural Development Bank and the Bawku East Small Scale Farmers

AssociationRuralBanks.

Othersareengagedinthepotterybusiness.Claypits,which,forages,havebeen

the source of material for earthenware production, are sited in several placesaround the district, as well as special colour pits of soil; red,black and white

products,atGooboknearZabgu.

2.BackgroundonKasennaNankanaDistrict(UpperEastRegion)

KassenaNankanaDistrict,oneoftheeightdistricts intheUpperEastRegionis

locatedinthenorthernpartofGhana.ItisborderedbytheRepublicofBurkina

Faso,andtheBolgatanga,Bonga,Builsa,SissalaandMamprusiWestDistricts.It

stretchesfor

55

kilometres

from

north

to

south

and

53

kilometres

from

east

to

west. The district capital is Navrongo. It has an area of about 1,674 square

kilometres.

TopologyandDrainage

Thetopographyislowlyingwithanaverageheightof100metresabovesea

level.Theterrainisundulatingwithisolatedhillsdottingthelandscape.


ThevegetationofthedistrictisoftheSudanandsavannahtypewithgrassland

separatingdeciduoustrees.

GeologyandSoil

The geology of the district comprises granite and shale, althouth the rock

formationsareactuallyofad

roof water harvesting

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