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  • SpringBoxDesignandConstruction

    CE5993

    Acknowledgment:Acknowledgment:LaurenFry

    Civil & Environmental EngineeringCivil&EnvironmentalEngineeringMichiganTechnologicalUniversity

  • Unprotected SpringUnprotectedSpring

    Figure1.UnprotectedspringinthevillageofBilikBikot,Cameroon.Beforei f h i b h i ll d ll i hiconstructionofthespringbox,thespringwaterwasallowedtocollectinthis

    openpool.Waterstagnated,peoplewereabletodipdirtybucketsinthepool,andthespringwasamosquitobreedingarea.

  • WaterRelatedDiseases

    (Cairncross andFeachem,1993)

  • Choosing a SpringChoosingaSpring

    Why people choose a specific source:Whypeoplechooseaspecificsource: Waterlookscleanerandtastesbetter. Itiscloserthanothersources. Theflowisconstantandsufficient.

    Other considerations:Otherconsiderations: Actualwaterquality(bacteriafree?Taste,odor) Abilityforwatertodrainy Reliabilitythroughdryseason Accessibilityy

  • Preparation of the SpringPreparationoftheSpring

    Atypicalarrangementofanunimprovedspring.Toprepareforspringboxconstruction,theimpermeablelayerofsandorsoilshouldberemovedatthespringpool,downtotheimpermeablelayer.

  • Spring Box Design: Profile ViewSpringBoxDesign:ProfileView

    (Filtermaybeomittedfromdesign.)

  • Spring Box Design: Plan ViewSpringBoxDesign:PlanView

    (Filtermaybeomittedfromdesign.)

  • Slow Sand FiltrationSlowSandFiltration

    Foraslowsandfiltertofunction,thesandshouldhaveaneffectivegrainsizeof0.15to0.30mmanduniformitycoefficient(D60/D10)lessthan5. D60isthesievesizethatallows60%ofthesandtopassand

    D10 i th i i th t ll 10% tD10isthesievesizethatallows10%topass. Minimumheightofthesandlayershouldbe0.5m,andthe

    rateoffiltrationshouldbenofasterthan0.1to0.23/ 2/h (Vi h t l 1987)m3/m2/h(Visscher etal,1987).

    Forafiltrationrateof0.1m/hthroughacleanfilter,theminimumheadoverthefilteris5cm(Tchobanoglous andB t 2003)Burton,2003).

    Evenwithasmallspringoutputlike1.7L/min,thesurfaceareaofthefiltermuststillbeatleast1.0m2.

  • Rapid Sand FiltrationRapidSandFiltration

    Filter may be omitted to save money or as aFiltermaybeomittedtosavemoney,orasacompromise,rapidsandfiltrationmaybeusedused.

    Forrapidfiltration,verycoarsesandorsmallgravel is usedgravelisused.

    Inthiscasethefilterisdesignedtobei l 0 5 l b 1 5 id b 1approximately0.5mlongby1.5mwideby1

    mhigh,withfiltermediaheightof0.4m.

  • ReservoirReservoir Thereservoirshouldbesizedbasedontheoutputofth i d t i i th t f tthesourceinordertomaximizetheamountofwaterthatisstoredovernight. Forexample,ifaspringhasamaximumoutputof6L/min,p , p g p / ,

    assumingthatnoonedrawswaterbetween6:30pmand5:30am(11hoursoffilling),thereservoirsizewouldbe3.96m3.

    Size may be restricted by available materials and funds, however.Sizemayberestrictedbyavailablematerialsandfunds,however. Reservoirwallsaremadeofsteelreinforcedconcrete. Floorshouldbeslopedandmadewithsmoothedconcrete.

    Allsurfacesinsidethereservoirshouldbesmoothedt ll f i l itoallowforeasiercleaning.

  • Typical Construction BudgetTypicalConstructionBudget

  • Typical Construction BudgetTypicalConstructionBudget

  • Typical Maintenance ScheduleTypicalMaintenanceSchedule

    Itisveryimportantthatthecommunityandmanagementcommitteearey p y geducatedandtrainedontheimportanceofmaintenancesotheprojectissustainableinthelongterm.

  • Measuring Spring DischargeMeasuringSpringDischarge

    Weirusedtodeterminetheoutputofthesprings.Awelderwashired to produce this weir from a flat piece of metal roofing materialhiredtoproducethisweirfromaflatpieceofmetalroofingmaterial.Allyieldandheadmarkingswerealsoengravedonthemetal(MannandWilliamson,1973).

  • ConstructionConstruction

    (Filtersizelimitedbymaterials.)

  • Typical Construction ScheduleTypicalConstructionSchedule

  • Completed SpringboxCompletedSpringbox

  • Completed SpringboxCompletedSpringbox

    Overflowpipebendsdowntopreventchildrenfrombreakingit.

  • Common Construction ProblemsCommonConstructionProblems Accidentallydiggingthroughtheimpermeablelayermaycause

    water to be lost from the springwatertobelostfromthespring. Whenfillingthewoodenformswithconcrete,unevenpressuremay

    causethewallstograduallytiltduringplacement. When filling the primary filtration and capture area there is a Whenfillingtheprimaryfiltrationandcapturearea,thereisa

    possibilityforblockingtheveinsaugmentingthespring.Besurethattheveinsarenotblockedbymud.C i th i filt ti d t ith th ft it Coveringtheprimaryfiltrationandcaptureareawithearthafteritisfilledwithrocksmaybeappropriateinsomeplaces,butwheresoilisveryfine,theearthmayendupfilteringthroughtherocksd bl k h l l h handblockingthegravellayerentrance.Inthiscase,theprimary

    filtrationandcaptureareacanbefilledwithrocksandcoveredwithaplastictarporotherimpermeablematerialbeforecoveringwithearth.

  • ReferencesReferences Cairncross, S., and R.G. Feachem. Environmental Health Engineering in the Tropics: an

    Introductory Text, Second Edition. Chichester: John Wiley and Sons, 1993. Fry, L. "Spring Improvement as a Tool for Prevention of Water-Related Illness in Four

    Villages of the Center Province of Cameroon," M.S. Report, Civil & Environmental Engineering, Michigan Technological University, 137 pages, 2004.

    Fry, L., J.R. Mihelcic, D.W. Watkins, Improving public health by improving water supply: y, , , , p g p y p g pp yresults from springbox projects in Cameroon. Journal of Engineering for Sustainable Development: Energy, Environment, Health, 2006.

    Huisman L., De Azevedo Netto J.M., Sundaresan B.B., Lanoix J.N., and Hofkes E.H. SmallCommunity Water Supplies: Technology of Small Water Supply Systems in DevelopingCommunity Water Supplies: Technology of Small Water Supply Systems in DevelopingCountries. IRC Technical Paper Series #18. The Hague, The Netherlands: IRC InternationalWater and Sanitation Centre, 1981.

    Tchobanoglous, G. and F. L. Burton. Wastewater Engineering: Treatment and Reuse. Metcalf& Eddy Boston: McGraw Hill 2003& Eddy. Boston: McGraw Hill, 2003.

    Visscher J.T., Paramasiram R., Raman A., and Heijnen H.A. Slow Sand Filtration forCommunity Water Supply: planning, design, construction, operation, and maintenance.Technical Paper Series #24. The Hague, The Netherlands: IRC International Water andS i i C 1987Sanitation Centre, 1987.