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The Homeowner’s Guide to Flood Prevention HOW TO IDENTIFY PROBLEMS & MAINTAIN YOUR HOME’S DRAINAGE SYSTEMS

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Page 1: Homeowner's Guide to Flood Prevention · 5 Top up sunken areas around the foundation. Ground around your basement settles over time. Raising that up with some dirt and shovel work

The Homeowner’s Guide to Flood Prevention

HOW TO IDENTIFY PROBLEMS & MAINTAIN YOUR HOME’S DRAINAGE SYSTEMS

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The Homeowner’s Guide to Flood Prevention is part of Flood Proof, the City of Edmonton’s Drainage Services Flood Prevention Program. It was developed as a direct response to the flooding of 4,000 Edmonton homes in July of 2004. For more information on the program, log on to www.edmonton.ca/floodprevention

Part of the Flood Proof program includes a free service called the Home Flood Prevention Checkup. A drainage specialist can help you identify drainage problems and solutions right at your home. See Chapter 7 for more details.

©2008 The City of Edmonton. Copyright of this publication, whether in print or electronic form, is held by the publisher. No person may reproduce copies of this publication for any purpose other than personal use without the written consent of the publisher.

Table of Contents

Introduction ..................................... 1

Chapter 1: Understanding Drainage ................. 2 HomeDrainageSystem MunicipalDrainageSystem

Chapter 2: Why Homes Flood ............................ 5 FiveQuick,InexpensiveWays ToGetYouStarted

Chapter 3: Eavestroughs and Downspouts ....... 8

Chapter 4: Improving Lot Grading .................. 11 HomemadeSlopeGauge ProductFocus:WindowWell BeKindtoYourNeighbours

Chapter 5: Backwater Valves, Weeping Tile and Sump Pumps ........................... 15 BackwaterValves BackwaterValveSubsidyProgram WeepingTile Permits SumpPumps

Chapter 6: Maintaining Your Home Drainage System ........................... 22 Outside - Eavestroughs&Downspouts - SplashPads&Extensions - LotGrading Inside - FoundationWalls - SumpPump - BackwaterValve - PlumbingFixtures - Fats,OilsandGrease

Chapter 7: Resources That Can Help ............... 24 CityofEdmonton - DrainageServicesInformation

andAssistance - HomeFloodPrevention

Check-up - DrainageandSewer

TroubleLine - DrainageServicesLotGrading PlumbersandLandscapers Do-it-yourselfResources AlbertaHealthServices

Chapter 8: Glossary of Terms .......................... 27

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Introduction 1

Introduction

Everyyear,millionsoflitresofwaterflowintothemunicipaldrainagesystemfromresidentialrooftopsandindoorplumbing.Mostpeopledon’tthinkabouthowthewateriscollected,orwhereitgoes.It’sadifferentmatterthoughwhenatorrentialstormcomes,thedrainagesystemfaltersorthereiswaterinthebasement.

Waterdamagefromfloodingcoststime,moneyandinconvenience.Fortunately,therearemanythingsyoucandotoreduceyourrisk.Preventionandmaintenancearethekeys.Lookingatyourhomenowandfixinganyproblemareasbeforethenextmajorrainstormcansaveyoualotofgrief.

TheHomeowner’sGuidetoFloodPreventioncontainsinformationthatcanhelpyouidentifyproblemareasandproperlyupgrade,repairormaintainyourhome’sdrainagesystem.Thisbookletisfilledwithpracticaldrainagetips,andprojectsthatyoucandoyourself.

Detailsofvariousprojects,relativecostsanddegreesofdifficultyareprovidedthroughout.Evenifyouprefertohireaprofessional,thisbookletoffersknowledgeandinsightsthatmayhelpyoumakeamoreinformedchoice.Itisrecommendedthatyouobtainthreequotesandaskforreferences,particularlyifyouareunfamiliarwiththecompanyorindividual.

DefinitionsofwordsorphraseshighlightedinboldcanbefoundintheGlossaryofTermsinChapter8.

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The Homeowner’s Guide to Flood Prevention2

Chapter 1Understanding Drainage

Inanycity,privateandpublicdrainagesystemsworktogethertochannelandmovesanitaryandstormwatersafelyawayfromhomesandneighbourhoodstreets.Theprivatesystemistheresponsibilityofresidentialandcommercialpropertyowners.Thepublicsystemisownedandoperatedbythemunicipality,inthiscasetheCityofEdmonton.

Figure 1: Illustration of servicing for a typical home

Home Drainage System

Thesanitaryservicedealswithallwaterdisposedofinsidethehome.Waterfromshowers,toilets,sinks,dishwashers,clotheswashersandfloordrainsischannelledtoapipeunderyourbasementfloor.Thispipeisconnectedtoalargersanitarysewerpipelocatedunderthestreetorthebacklane.

(See page 3*)

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Chapter 1: Understanding Drainage 3

Thestorm sewerdealswithroofandsurfacewaterthatcomesfromrainfallorsnowmelt.Slopedlawnsanddrivewaysdirectwaterfromtheroofandthegroundtothestreetorthebacklane,wherecatchbasinsarelocated.Thecatch basinsareconnectedtolargeundergroundstormwaterpipes(SeeFigure1).

Waterthatseepsthroughthegroundiscollectedbyweepingtilelocatedatthebottomofyourhome’sfoundation.Weeping tileiseitherconnectedtoasumppump,whichsendsexcesswateruptothesurface,ortoasewerpipeunderyourbasementfloor(SeeFigure1).

InsomeEdmontonneighbourhoods,homeshaveaseparatestormservice.Inthesehomes,roofdownspoutsgointothegroundandconnecttothepipe.Thispipesendsthewatertoalargerstormwaterpipelocatedunderthestreetorthebacklane(SeeFigure2).

Downspoutsmaystillbeconnectedtoahome’ssanitaryservicepipeinneighbourhoodswithacombined sewer service,howeverthistypeofconnectionhasnotbeenallowedintheCityofEdmontonsince1988(SeeFigures1and3).

Figure 2: Illustration of separate stormwater pipe servicing in older areas

Figure 3: Illustration of servicing for homes in combined sewer area

Eavestrough

Stack (Vent Pipe)

Downspout

Road

Weeping Tile

Sanitary Service Line

Runoff

Stack (Vent Pipe)

Road

Weeping Tile

Sanitary Service Line

Eavestrough

Downspout

Storm Standpipe

Storm Service Line

*

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The Homeowner’s Guide to Flood Prevention4

Municipal Drainage System

Thesanitaryservicecollectssewageand“grey”waterandsendsittoeithertheGoldBarWastewaterTreatmentPlantortheAlbertaCapitalRegionWastewaterTreatmentPlantforprocessing.Attheplants,thesolidwasteisremovedandthewateriscleanedbeforebeingreleasedintotheNorthSaskatchewanRiver.

Thestormwatersystemcollectsrainwaterandsnowmeltandchannelsitviapipesoroverlandroutestodry ponds,stormwater lakes,creeks,ravines,ordirectlyintotheNorthSaskatchewanRiver.Sinceabout1980,stormwaterlakestoservicenewEdmontonneighbourhoodshavebeenmandatory.

AcombinedsewersystemexistsinEdmontonneighbourhoodsbuiltbeforethemid-1960s.ThecombinedsewersystemcollectssanitaryandstormwaterinthesamepipeandsendsittotheGoldBarWastewaterTreatmentPlantforprocessing.In2005,about13%ofallhomesinEdmontonwereservicedbyacombinedsewersystem.

Stormwater lake

Dry pond

Outfall

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Chapter 2: Why Homes Flood 5

Chapter 2Why Homes Flood

Edmontongetsabout345millimetres(14inches)ofraineachyear.Mostofthiscomesintheformofthundershowersorsummerstorms,anyoneofwhichcandropalargeamountofwaterinaconcentratedareainashortperiodoftime.Whenamajorrainstormhits,thehugevolumeofwaterthatoccurscanoverwhelmdrainagesystemsandcauseflooding.Snowposesasimilarthreatinthespringifthereisarapidsnowmelt.

Duringarainstorm,thepressureonyourhomedrainageandthemunicipaldrainagesystemsincreasesdramatically.Theconditionandcapacityofthesesystemsareequallyimportantinmanagingwetweather.Blockedorbrokenpipes,poorlotgrading,excesshailandotherfactorscanrestricttheflowofwatersubstantiallyincreasingtheriskofflooding.

InEdmonton,themunicipalstormwaterdrainagesystemdesignstandardisoneinfiveyears.Thismeansthesystemcanhandleanytypicalrainstormbutcouldhaveitscapacityexceeded,onaverage,onceeveryfiveyears.Thisisbasedonhistoricalweatherpatterns.Themunicipalsanitarysystemdesignisbasedonsewageflows,plusanallowanceforwaterthatgetsintothesystemduringwetweather.

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The Homeowner’s Guide to Flood Prevention6

Whenthevolumeofstormwaterexceedsthemunicipalsystem’scapacity,surfacepoolingoccurs.Someofthisexcesswateralsofindsitswayintothesanitarysystem.Thiscreatesaddedpressureonsanitarypipes,includingthoseexitingfromhomes.Toprotecthomesasmuchaspossible,CityofEdmontonbylawssince1989haverequiredthateachnewhomehaveabackwater valvetoprotectagainstsewerbackup.

Lotgradingmusthaveapositiveslopeof4–6inchestoaminimumoffivefeetawayfromthehome’sfoundation.Also,downspoutextensionsorsplashpads,windowwells(whererequired)andweepingtileconnectedtoasumppumparerecommended.

Often,homesthatfloodaremissingoneormoreofthesecomponentsorthecomponentsarefoundtobeinpoorworkingorder.Thelocationofahomecanalsomakeadifference.Forexample,homesbuiltinlowlyingareasornexttolakeshaveagreaterfloodrisk,assurfaceandgroundwaterwillnaturallydraintotheseareas.Otherfloodriskfactorsincludelotelevation,styleofhome,servicingelevation,surfaceconditionsandwaterdrainagefromneighbouringproperties.

Homeownerbehaviourduringastormcanalsoincreasetheriskofflooding.Forexample,washingclothes,takingashower,runningthedishwasherandflushingyour

Flushing a toilet during a storm can increase flood risk

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Chapter 2: Why Homes Flood 7

toiletsaddswatertoasystemthatmayalreadybeoverloaded.Thewatermayhavenowheretogobutupyourfloordrainandintoyourbasement.Thisisparticularlytrueifyouhaveabackwatervalve.Thevalveisdesignedtocloseduringextremeconditionsandkeepoutsidewaterfromgettingin.Whenthishappens,waterfromtheinsidealsocan’tgetout.

Manypeopleforgettoputtheirdownspoutextensionsdownbeforeitrains.Alongdownspoutextensionisofnovaluewhenit’sproppedupagainstthesideofthehouse.Ifyouhaveasumppump,doublechecktoseethatitispluggedinandthebreakerisonduringastorm.Morethanonehomeownerhassearchedforthecauseofafloodedbasementonlytodiscoverthesumppumplackedthepowertoperform.

Five Quick, Inexpensive Ways To Get You Started

Anassessmentofyourhomedrainagesystemmayhavepointedoutanumberofdeficiencies.Sowheredoyoustart?Herearesomequick,inexpensiveactionsyoucantakethatwillmakeadifferenceinreducingyourfloodrisk.

1 Plug the leaks.Aladder,silicone,andtimeareallyouneedtosealholesorcracksinyoureavestroughs,downspouts,extensions,sidewalks,patioanddriveway.

2 Repair or replace downspout extensions.Thismightbeamatterofsimplyputtingdowntheextensionthat’salreadythereorputtingbackthesplashpad.Purchasingandinstallingextensionsorsplashpadsisinexpensivebutveryimportantingettingwaterawayfromfoundationwalls.

3 Clean your eavestroughs and downspouts.Thedownspoutextensionshavelittlevalueifleaves,andotherdebrisarepreventingwaterfromgettingdownthedownspout.Aglovedhand(orgardenspade),ladderandgardenhosearewhatyouneedtogetthejobdone.

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The Homeowner’s Guide to Flood Prevention8

4 Backfill under steps and decks. Thisisoftentheweakspotinlotgrading.Dirtandsomeshovelworkisallittakestofillthedepressionandgetthegroundslopingdownhillawayfromthehouseagain.

5 Top up sunken areas around the foundation.Groundaroundyourbasementsettlesovertime.Raisingthatupwithsomedirtandshovelworkwillre-establishapositivegradeagainatlittleornocost.

Chapter 3Eavestroughs and Downspouts

Onanyproperty,thefirstpointofdefenceindealingeffectivelywithrapidsnowmeltorarainstormistheeavestroughsanddownspouts.Just10mm(0.4inches)ofrainontheroofofanaveragesizedbungalowgenerates1,200litresofrunoff.Catchingwaterfromtheroofanddirectingitawayfromthewallsofthehousearecriticalfactorsinkeepingyourbasementdry.Eavestroughs,alsoknownasrain gutters,arelocateddirectlybelowtherooflineofyourhome.Eavestroughscatchroofrunoffandchannelittodownspoutsthatarenormallylocatedatthebottomcornersoftheroof.

Thestandardresidentialeavestroughordownspoutisfourorfiveincheswide.Theyaremadeofplasticoraluminiumbutplasticismorecommonlyused,asitissturdierandeasiertoworkwith.Theycomeinonestandardlengthbutcanbeeasilycuttothedesiredsize.Elbows,endcaps,Tsandstraightconnectorsareallpre-castsoanyroofsizeorshapecanbeaccommodated.

Eavestroughsanddownspoutsshouldbecleanedregularlyofleavesanddebrissowaterflowisnotblocked.Specialhardmeshscreenscanbepurchasedtositontopofeavestroughstopreventleavesandlargeobjectsfromentering.

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Chapter 3: Eavestroughs and Downspouts 9

Youcantesttheeffectivenessofyoureavestroughsbypouringwaterattheendfurthestawayfromthedownspout.Ifwaterleaksoutorpoolsatanypointyouneedtoclean,repairorreplaceit.

Eavestroughsshoulddirectwateronagentleslopedowntowardsthedownspout.Usealevelinsidetheeavestroughtocheckthatthedownhillgradeisconsistentfromoneendoftheeavestroughtothedownspout.Sometimesasaggingeavestroughcanberepositionedtopreventpoolingandre-establishthegrade.Ifthisisnotpossible,replaceit.

Eavestroughleakstypicallyoccuratjoints.Fortunately,theycanberepairedquicklyandeasilywithsilicone.Siliconecomesinatubeandisusuallyclearorwhite.Oncedry,itiswaterresistantandstandsupwelltoextremetemperatures.Whenrepairingaleak,doitfromtheinsideoftheeavestrough.Makesurethesurfaceiscleananddrybeforeapplyingthesilicone.

Theeavestroughshouldbereplacediftheleakisfromalargeholeorcrack.Whenreplacinganeavestroughordownspout,makesuretosealallconnectorjointsandendcapswithsilicone.

Downspoutsarehollowpipesthattakewaterfromtheeavestroughandchannelittotheground.Ideally,thedownspoutshouldendinanelbowandextensionthatdirectsthewater1.8metres(sixfeet)awayfromthehouseandtowardsthestreetorbacklane.Theextensionshouldbeata30degreeormoreangleinrelationtotheground.InEdmonton,itmustendatleast15centimetres(sixinches)insideyourpropertyline.Makesurethewaterisnotdirected

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The Homeowner’s Guide to Flood Prevention10

ontoyourneighbour’sproperty.Youcanbefinedupto$1,000fordischargingontoanotherproperty.

Professionalsusedownspoutmaterialforextensions.Thisispreferredbecausetheyaredurableandveryeffectiveinchannellingwaterawayquickly.Leavetheextensiondownallofthetimeorputitdownwheneverrainisforecast.Analternativetoharddownspoutmaterialisasoftplasticextension.Thistypeofextensionrollsoutwhenitrainsandcanbepurchasedathomeimprovementstores.Anyextensionshouldbecheckedregularlyforleaksandtoensurethatitisfunctioningproperly.

Somesideyardsaretoonarrowtoallowforalongdownspoutextension.Inthesecases,splashpadsshouldbeused.Standardsplashpadsaretwofeetlong,aremadeofconcreteorplastic,andareboltedorhungonthesideofthehouseata30degreeangle.Thedownspoutendswithinafewinchesofthesplashpad,whichinturndirectsthewaterawayfromthefoundationofthehouse.

Downspoutextensionsorsplashpadsshouldneverberemoved.Theyprotectyoufromanumberofpotentialproblems.Wateralongthebasementwallsofyourhousecanseepthroughtinycracksandcauseadamp,clammybasement.Leftunchecked,thiscaneventuallydamagethefoundationofyourhouse.

Waterthatseepsdownyourbasementwallsandintoyourweepingtilecanoverloadthesanitarysewersystem,causingasewerbackup.Itmaycreateextraworkforyoursumppump,ifyouhaveone,andcouldcausepumpfailureundersevereconditions.

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Chapter 4: Improving Lot Grading 11

An Exception to the Rule: InmanyolderEdmontonhomes,roofdownspoutsaredirectlyconnectedtoanundergroundseparatestormsewerpipe.Inthesecases,disconnectingaroofdownspoutfromthepipemaynothavemuchimpactinreducingafloodrisk.Infact,itmayincreasetheriskifthelotisnotproperlygradedtodrainwaterawayfromthehome.

Chapter 4Improving Lot Grading

Goodeavestroughs,downspoutsandextensionshelpmakeyouroutdoordrainagesystembetterbutitcan’tmakeupforpoorlotgrading.Properlotgradingisoneofthemostimportantthingsyoucandotopreventwaterfromgettingintoyourhome.Since1997,theCityofEdmontonhasrequiredeverynewhometohaveanapprovedlotgradingplan.

Lotgradingstartsatyourbasementwall.Walkaroundyourhomeandmeasuretheslope fromthewall.Thisincludesunderstairs,stepsanddecks.Thedirtorsodshouldslopedownfromthewallatacontinuousangleforatleastfivefeet.Ifthesurfaceisdecorativerock,barkoranotherporousmaterialthatletswaterthrougheasily,takethemeasurementfromwherethedirtbegins.

Thesoilatyourbasementwallshouldbeatleast15centimetres(6inches)higherthanthegroundfivefeetaway.Useaslopegauge(seebox)toseeiftheangleoftheslopeisadequate.

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The Homeowner’s Guide to Flood Prevention12

Placethelongendofyourslopegaugeagainstthebasementwallandtheshorterendontheground.Thehorizontalboardshouldbelevel.Ifitisnot,addsoilatthebasementwalluntillevelisachieved.

Onceitislevel,fillinthespaceunderneaththeslopegaugeallthewaytotheend.Usethisasaguideforbackfillingallthewayaroundyourhome.Packdownthesoilwithashoveloryourfoot.Checkevery5-6feetwithyourslopegaugetomakesuretheangleisstillright.

It’simportanttobackfillunderneathyourstairs,stepsanddecksaswell.Usethesameangleasaroundtherestofthehouseevenifthebottomstairorstepislessthanfivefeetfromthebasementwall.

Remember:Groundsettlesovertimeparticularlynearbasementwalls.Youshouldcheckyourgradeeveryyearandaddsoilwherenecessary.

Homemade Slope Gauge

It’seasytomakeaslopegauge.Cuta2x4intoonefivefootlengthandonesixinchlength.Placetheshorterpieceverticallyonend.Placethelongerpiecehorizontallyontop.Nailorscrewtheendofthehorizontalpieceontotheendoftheshorterpiece.Tieorplacealevelontopofthehorizontalpieceandyouarereadytogo!

6”

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Chapter 4: Improving Lot Grading 13

Window wellsshouldbeusedwherethebottomofabasementwindowisatorneargroundlevel.Theynotonlyallowforpropergradingbuttheyalsopreventdirtfromrottingwindowsills.AwindowwellisaU-shapedribbed,lightmetalproductthatcanbepurchasedinmosthardwarestores.Theycomeinvariouswidthsandheightssomeasureyourwindowbeforepurchase.

Theouteredgesofthewindowwellshouldsurroundthewindowandbetightagainstthebasementwall.

Thebottomofthewindowwellshouldbeatleastafootbelowthebottomofthewindowsill.Theareainsidethewindowwellshouldbeclearedofdirtandbackfilledwithloosegravelorrock.Thisshouldbedonefromthebottomofthewelltothreetosixinchesbelowthebottomofthewindowsill.Thiswillallowwatertoeasilydrainandfilterdowntothefoundationweepingtile.Thedirtorsodontheoutsideofthewindowsillshouldbegradedliketheremainderofthehouse.

Insomecases,housesmayhaveexistingwindowwellsthatdon’tdrainproperly.Inextremecases,apipemayhavetobeinsertedthatrunsdirectlyfromthebottomofyourwindowwelltowardsyourweepingtile.Seektheadviceofaprofessionalbeforedoingsuchwork.

Window Wells

• Variouswidthsandheights.Measureyourbasementwindowbeforepurchase.

• Galvanizedsteelconstruction.

• Easytoinstall.

Product Focus

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The Homeowner’s Guide to Flood Prevention14

Be Kind to Your Neighbours

Theslopingofyourlotmustfollowthesamerulesasdownspoutextensions(seeChapter3).Watershouldbedirectedtothebackalleyorthestreet,andnotintoyourneighbour’syard.Thiscanbetrickywhenthespacebetweenhousesisnarrow.Onesolutionisforyouandyourneighbourtocreateslopedowntowardsacommonpropertyline.Thiscreatesaswale thatcanthenchannelwatertowardsthealleyorthestreet.

Yourpropertymaynotallowforthis.Forexample,youmayhavearetainingwallorhighgroundatthepropertyline.Insuchcases,youcancreateaninternal swale.Thismeanshavingaslopefromthehouseandaslopefromthehighgroundmeetinthemiddleoftheyard.Thisswalecanthenbedirectedtochannelwatertowardsthealleyorthestreet.

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Chapter 5: Backwater Valves, Weeping Tile and Sump Pumps 15

Insomecases,aneighbour’spropertymayhavetherightgradingbutbelowerthanyours.Aretainingwallalongthepropertylineisagoodsolutiontothisproblem.Thiscanbedoneinfrontofanexistingfenceorotherfeatureyoudon’twantdisturbed.Thewallallowsyoutocreateaninternalswalethatcansafelychannelwateraway.

Itisalwaysbestifneighbourscandiscussandresolvelotgradingissuestogether.CityofEdmontonLotGradingInspectorscaninvestigatecomplaintsorconcernsaboutsurfacewaterdrainage.Theyalsowillvisityourhomeifyouhaveanydoubtsaboutwhattodoaboutlotgrading.

Chapter 5Backwater Valves, Weeping Tile and Sump Pumps

Floodpreventiondeviceslikebackwatervalvesandsumppumpscanbevaluablehomedrainageassetsbutnoteveryoneneedsone.Consideryourentirehomedrainagesystem,whattypeofhomeyouhave,whereyoulive,methodofservicingandyourfloodinghistorybeforerushingouttobuyandinstallthesedevices.

Backwater Valves

Abackwatervalvesitsinsideahome’sbranchormainsanitarysewerline.Itsjobistopreventsewagefromreturningupa

Backwater Valve Subsidy Program

Since1991,theCityofEdmontonhasofferedabackwatervalvepurchaseandinstallationsubsidyprogram.Homesthatsuffersanitarysewerbackupduringastormeventareeligiblefortheprogram.

In2009,thesubsidywastoamaximumof$1,200.Someconditionsapplyandanapprovalisrequiredbeforeinstallation.ContactDrainageServicesat780-496-5591tofindoutmoredetailsabouttheprogram.

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The Homeowner’s Guide to Flood Prevention16

sanitarysewerlineandenteringthebasement.Itisaneffectivelastlineofdefenceandisrecommendedforallhomesthatareatriskofflooding.

Therearetwotypesofbackwatervalves.Bothworkwell,butitisimportanttoinstalltherightone.Themainsanitarysewerlineenteringahomeneedsa ventedbackwatervalve.Branchlinescomingoffthemainlineneeda non-ventedvalve.Youmayneedmorethanonevalvedependingonyourhome’sinternalplumbing.Aqualifiedplumbercantestyoursystemandrecommendthecorrectinstallation.

Duringastorm,sanitarywastewatertryingtoflowbackintoahomecausesthebackwatervalvetocloseitsflap.Thisactionpreventssewagefromre-enteringthehome,butitalsomeanswaterfrominsideyourhomecan’tgetoutuntilthevalvereopens.

Remember:Whenthevalveclosesthesewerline,youshouldnotusethetoilet,sink,shower,washer,dishwasheroranyotherelementthatdischargeswastewater.Thewastewaterwillhavenowheretogoexceptupthefloordrainandintoyourbasement.

Backwatervalvesneedbecleanedandmaintainedtoworkproperly(Chapter6).Also,olderbackwatervalveshavemetalflaps.Thesecancorrodeovertimeandbegintostick.Oncethisoccurs,theyshouldbereplacedwithavalvethathasaplasticflap.

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Chapter 5: Backwater Valves, Weeping Tile and Sump Pumps 17

Weeping Tile

Weeping tileisaperforatedplasticpipethatsurroundsthefoundationofahome.Itsitsinabedofgravel.Thisallowsexcessgroundwatertoseepintoit.Thiswaterischannelledtoasumppump,orthesanitarysewersystem,orthestormwatersewersystem,dependingontheageofthehome.

Fordevelopmentpriorto1988,weepingtileflowsweredirectedtothesanitaryandcombinedsewersystems.Asof1988,newdevelopmentisrequiredtodirectweepingtiletothestormsewersystemwhereavailable.

Installingorrepairingweepingtileisexpensivebutnecessaryinsomecases.Forexample,weepingtilethatiscollapsedorcloggedbydebrisshouldberepairedtopreventdamagetothefoundationandbasementwalls.Youshouldseekprofessionaladvicefromaplumberorqualifiedcontractorbeforemakinganydecisions.

Sump Pumps

Over60,000homesintheEdmontonregionmayneedtheirsumppumpsreplacedinthenextfiveyears.Yoursmaybeoneofthem.

Themajorityofhomesbuiltsince1988haveasumppump.Aworkingpumpplaysanimportantpartinfloodprevention,channellinggroundwateroutandawayfromthehome.Ifyourhomewasbuiltafter1988,youshouldbeawareoftheconditionofyourpumpandwhetheritneedsreplacing.Agoodqualitypumpshouldlastaround10years,dependingonhowoftenitisworkingandtheacidityanddirtinessofthewater.

Permits

AddingdrainagecomponentslikeabackwatervalveandweepingtilerequiresaplumbingpermitfromtheCityofEdmontoncall311forallpermits.

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The Homeowner’s Guide to Flood Prevention18

So,howcanyoufindoutwhetheryouneedanewpump?And,ifyouneedtoreplaceit,whatshouldyoulookforinanewpump?

Finding and Testing Your Sump Pump

Differentmanufacturershavedifferentrecommendationsfortestingandmaintainingyourpump.Somerecommendrunningthepumpeverytwotothreemonths,othersrecommendayearlytest.Followanyrecommendationsprovidedbythemanufacturer.Thepumpshouldbelocatedinashallowpit(orsump)atthelowestpointinyourbasement.Onceyou’velocatedthepump,youcanperformasimple3-steptesttoensurethepumpisworkingproperly:

1 Checktomakesurepowerisrunningtothepumpcircuit.

2 Pourenoughwaterintothesumppitforthepumptobeginworking.

3 Checktheoutsidepipetoensurethatwaterisflowingfromthedischargelineoutsideyourhome.Insomecases,thepumpmayseemtorunbutnotpumpwater.

Ifyoutestthepumpanditisnotworkingproperly:• Checkfordebrisblockingthesuctionintake.• Listenforstrangenoisescomingfromthemotor.• Checkforoilinthesumpwell(mayindicateafailedpumpseal).• Iftheactivatingswitchforthepumpworksonafloat,checkthat

thefloatisnotrestricted.

Dependingontheproblemsyouencounteryoumaywanttoconsidergettingyoursumppumpservicedorreplaced.

Caution: maintenance should be done by a qualified technician.

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Chapter 5: Backwater Valves, Weeping Tile and Sump Pumps 19

Other Factors

Freezing:Ifyourpumpisoperatingduringfreezingweatherthereisariskoffreezingandlineblockage.Topreventproblemsitisbesttodisconnectoutsidehosespriortowinter.

Recycling:Ifwaterfromyoursumphosedischargestooclosetoyourfoundation,thewatermayrecycleandendupbackinyoursystem,possiblyendangeringyourfoundation.

What to Look for When Replacing Your Sump Pump

Therearesomebasiccriteriaforchoosingapump:sizeorcapacity,pumptypeandhorsepower.Thereareotherfactorsspecifictoyourhomethatmayalsoinfluenceyourchoiceofpump,suchasthevolumeofwateryourdrainagesystemhastohandleortheamountofgritinthewater.Intheend,youhavetobalanceyourneedswithhowmuchyouwanttopay.Youcanbuyacheaperpumpbutdon’texpectittoperformaslongoraswell.Ahigherqualitypumpisbuiltfromtopqualitycomponents.

Horsepower (hp)• Minimum1/3hprecommended.

Size/Capacity/Performance• Makesuretosizeyourpumpproperlytoensuregreatestefficiency.• Getinformationonthepumpcapacity(theamountofwater

pumpedingallonsperminute)andtheheightanddistancethewaterneedstotravel(referredtoas“head”).

• Toavoidclogging,thepumpshouldbeabletopassstonesofupto10millimetresthroughthepipes.

• Pumpingheadshouldbeaminimumofapproximately10feet.• Dischargelineshouldbe11/4inchpipe.

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The Homeowner’s Guide to Flood Prevention20

Pump Type, Back-up Systems and Alarms• Commontypes:submersible,pedestalandwater-powered.• Submersibleismostcommon.• Pedestaltypemaybebetterinhighlycorrosiveareas.• Water-poweredpumpsarenotasefficientaselectric.• Itisagoodideatohaveaback-upsystem(waterpoweredorbattery)

oranalarmtowarnyouifyourpumpfails.• Back-upsystems:water-poweredorbattery.

QualityPumpsaretestedagainstgeneralstandardsandratedaccordingly.Beforepurchasingapump,checkwhetherthepumpmeetsCSAstandardsanddisplaysa“CSAApproved”sticker.

Sump Pit Requirements

Ifyoursumppitisincorrectlysized,itwillaffecttheoperationofthepump.Thepumpismostefficientwhenitisworkingatitsoptimalflowrate,basedonthecapacityofthepit.TheCity’sbuildingcodesetsoutminimumrequirementsforsumppitsize:

Pit depth: 750 mm Pit area: 0.25 square meters (0.56 m diameter for circular sumps)

Asumppitcoverisrequired,andshouldbechild-proof.

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Chapter 5: Backwater Valves, Weeping Tile and Sump Pumps 21

Purchasing Checklist(usetocomparemodelsyouareconsideringforpurchase)

Feature Minimum requirement Model: Model: Model:

Horsepower (hp) rated 1/3 hp

Pump capacity(gallons per minute)

specific to each home

Pump head (sumplevel to pipe exitfrom home)

approx. 10 to 12 ft.

Solids handling allows stones up to 10 mm to pass

Discharge line size 1 1/4 inch pipe

Check valve recommended

Back-up system /alarm recommended

Warranty generally 1-2 years

Approved byCanadian StandardsAssociation

recommended

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The Homeowner’s Guide to Flood Prevention22

Chapter 6Maintaining Your Home Drainage System

Regularmaintenanceofyourhomedrainagesystemcanoftenbethedifferencebetweenstayingdryorbeingflooded.Onceayear,it’sagoodideatoevaluatetheconditionofyoursystem–insideandout.Ifyoufindaproblem,makefixingitapriority.

Remember: Mostfloodingonprivatepropertyiscausedbythefailureofoneormorehomedrainageelements.

Thischapterprovidesamaintenancechecklistyoushouldrevieweachyear.Ifyouareunsureofwhattodo,callaprofessional.

Outside

Eavestroughs & Downspoutsü Cleanleavesanddebrisfrominsidethetroughanddownspouts.ü Tightenelbowsandotherconnections.ü Caulkandsealanyleaks.ü Repairorreplacesagging,badlydentedorcrackedsections.

Splash Pads & Extensionsü Reconnectanyloosepadsorextensions.ü Replacebadlydentedextensions.ü Checksoftplastic,rolloutextensionsforleaksandtodetermineif

theyworkproperly.

Lot Gradingü Checktheslopefromthebasementwall.ü Checkforsettling,particularlyunderstairsanddecks.ü Raiseanylowspots.ü Lookforcracksorspacesondriveways,sidewalksandpatiosthat

arenexttothefoundationwall.Caulkorwaterproofwhereneeded.

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Chapter 6: Maintaining Your Home Drainage System 23

Inside

Foundation Wallsü Checkformoisturealongthewallsandthefloor.ü Fillandsealanyvisiblecracks.

Sump Pumpü Checkforpower.ü Testthepumpbypouringwaterintothepumpwell.ü Checktheoutsidepipetoconfirmwaterisflowingtowardsthe

streetorbacklane.ü Checkandrepairanyleaksinthesumppumppipe.ü Disconnectsumppumpdischargehoseinwinterconditionsto

avoidfreezingintheline.

Backwater Valve ü Openthetopandcleanoutanydebris.ü Checktheflapper.Makesureitismovingfreely.

Plumbing Fixturesü Maintainproperwaterlevelsintrapsinfloordrainsandtoiletsto

minimizeodours.

Fats, Oils, and Grease - Store it, don’t pour it.

Pouringfats,oils,andgrease(FOG)downyourdraincancausesignificantproblemsinyourhomesewersystemastheFOGsolidifiesinyourpipesandcausessewerbackup.TheresultcanbepropertydamageandconsiderableexpenseandinconveniencetoyouandtotheCity.

Storeyourusedfatsandgreaseinadisposablecontainer.Whenitisfull,putitinthegarbage.Usedcookingoilshouldbecooledandputintoacoveredplasticbottle,labeled,andputoutforgarbagecollection.Ifyouneedtodisposeoffourormorelitresofusedcookingoil,takeittoanEcoStation.

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The Homeowner’s Guide to Flood Prevention24

Chapter 7Resources That Can Help

Thereareanumberofpeopleandorganizationsthatcanhelpyouifyouareconcerned,orneedhelpwithyourhomedrainagesystem.

TheCityofEdmontonwww.edmonton.ca/floodprevention

Thiswebsitecontainseducationandprogramsupportinformationrelatedtofloodprevention.Moredetailsconcerningthefollowingservicescanbefoundthere.

DrainageServicesInformationandAssistance780-496-5454

Callthisnumberduringofficehourstogetreferralstoquestionsyoumayhaveaboutdrainageconcerns,inspections,orprogramsandservicesofferedbytheDrainageServicesBranch.

HomeFloodPreventionCheck-up780-944-7777

TheHomeFloodPreventionCheck-upisfreeandavailabletoallEdmontonresidentialhomeowners,providedthatthepropertyhasnotrecentlyreceivedaFinalGradeApproval(inthelastfiveyears).Onecallschedulesadrainagespecialisttocometoyourhomeforaone-on-one drainage assessment.Usinganevaluationchecklist,thespecialisthelpsyouidentifyanydeficienciesinsideandoutsideyourhome,andprovidesrecommendationsonwhattodotominimizeyourriskofflooding.

Begunin2005asapilotproject,theserviceoperatesfromspringtofall.Check-upscanbescheduledweekdays,eveningsorSaturdays.

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Chapter 7: Resources That Can Help 25

DrainageandSewerTroubleLine311

Thisisa24-houremergencyresponseservicethatyoushouldcall:• Ifyouareexperiencingadrainageproblemonyourproperty.• Ifyouseeadrainageproblemonthestreet.• Ifyougetanybasementfloodingasaresultofarainstorm.• Ifyouconsistentlysmellsewerodourscomingfromacatchbasin

ormanhole.

DrainageServicesLotGrading780-496-5576www.edmonton.ca/lotgrading

Callthisnumberforalllotgradingconcerns.Afternormalbusinesshoursthisnumberwillcallforwardtoavoicemailsystem;provideyourcontactinformationtoreceiveacallbackfromagradingspecialisttoanswerquestionsandprovidegradingadvice.Basedonthesituation,alotgradinginspectormayvisityourhometohelpyoudealwithanyunusualgradingissuesortohelpyoutoresolveagradingproblem.

PlumbersandLandscapers

Ifyouwouldlikeprofessionalhelpcorrectingadrainageproblem,looktoprofessionalplumbersandlandscapersforhelp.ListsofplumbersorlandscaperscanbefoundintheYellowPagesorbycontactingtheBetterBusinessBureauofCentralandNorthernAlbertaat780-482-2341.TheBetterBusinessBureaucanprovideyouwithcompanyreports24hoursaday.Regardlessofwhomyoucontact,it’sagoodideatogetthreeestimatesandreferencesbeforechoosingacontractor.

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The Homeowner’s Guide to Flood Prevention26

Do-it-yourselfResources

Ifyouplanondoingtheworkyourself,youcangetalotofsupportandinformationfromhardware,homeimprovementandplumbingsupplystores.Manyofthestaffaretradeprofessionalsandareusuallymorethanhappytosharetheirknowledgeandexpertisewithyou.

AlbertaHealthServices 780-735-1800

Leakyorfloodedbasementsmaybecomeahealthriskifclean-upisnotdonequicklyandcorrectly.Thisenvironmentalhealthservicesunitcanprovideinformationandadviceinresponsetoinquiriesaboutpotentialhealthrisks.

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Chapter 8: Glossary of Terms 27

Chapter 8Glossary of Terms

Backwater valveAbackwatervalveislocatedinahouse’ssanitarysewerline.Thevalveclosesunderpressure,preventingsewagefromreturningupthelineandbackintothehome.

Catch basinAcatchbasincollectsstormwaterfromthestreetthroughanopenmetalgrateandchannelsittoanundergroundstormwaterpipe.Belowstreetlevelisatrapwheresand,gravelandothermaterialiscapturedforremoval.

Combined sewerAcombinedsewercollectsbothstormwaterandwastewaterinthesamepipe.Sinceabout1960,combinedsewersarenolongerbuiltinEdmonton.

DownspoutAdownspoutisalengthofpipethatisconnectedtoaneavestroughandrunsverticallyfromtherooftotheground.

Downspout extensionAdownspoutextensionisalengthofpipethatisconnectedtobottomofthedownspoutandrunsatadownwardangleawayfromabuilding.

Dry pondAdrypondisaman-madedepressioncreatedtocapturesurfacerunoffduringmajorrains.

EavestroughAneavestroughisattacheddirectlybelowtheroofline.Itcollectsstormwaterfromtheroofandchannelsittoadownspout.

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The Homeowner’s Guide to Flood Prevention28

Grey waterGreywaterisliquidsewage.

Internal swaleAswaledesignedtohandlesurfacewaterentirelywithinaproperty.

Lot gradingLotgradingreferstothewayinwhichthesurfaceofapropertyissloped,particularlyfromthewallsofabuildingtothepropertyline.

Rain gutterAraingutterisanothernameforeavestrough.

Sanitary serviceThesanitarysewerservicecollectssewageandgreywaterfromhomesandbusinessesanddirectsittoaplantfortreatment.

SlopeAslopeisanyinclinedportionofgroundorearththatdirectswaterinaspecificdirection.

Splash padAsplashpadisaconcreteorplasticchannelthatcanbeattachedtothesideofabuildingandsitsatanangleunderadownspout.Itchannelsstormwaterfromthedownspoutawayfromthebuilding.

StormwaterStormwatermeansanysurfacerunoffthatistheresultofnaturalprecipitation.

Stormwater lakeAstormwaterlakeisabodyofwaterthatisdesignatedtocollectandcontainstormwaterfromasurroundingarea.Thelakemaybenaturalormanmade.

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Chapter 8: Glossary of Terms 29

Storm sewerThestormsewercollectsrainwaterandsnowmeltandchannelsitviapipestocreeks,ravines,dryponds,stormwaterlakesortheNorthSaskatchewanRiver.

Sump Abasementsumpisapitinthegroundunderthebasementfloorthatcollectsexcessgroundwaterfromweepingtileorsurroundingsoil.

Sump pumpAsumppumpisamotorizedmechanicaldevicethatkeepsbasementsdrybypumpingexcesswaterfromasumptothesurface.

SwaleAswaleisashallow,slopedchannelinthegroundthatconveyswaterinaspecificdirection.

Weeping tileWeepingtileisaperforatedpipethatsurroundsthefoundationofahomeandcollectsexcessgroundwater.Insomehomes,thisexcesswaterisreleasedtoasumppump,whichcarriesittothesurface.

Window wellAwindowwellisacorrugatedmetalproductthatsurroundsabasementwindowatorbelowgroundlevel.Installationallowsforproperlotgradingaroundthebasementwindow.

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More information on the Flood Proofing program can be obtained by calling 780-496-5591. The 24-hour Drainage and Sewer Trouble hotline can be accessed by calling 311. Additional information can be viewed online by

visiting our website at www.edmonton.ca/floodprevention

Floodingcausedbyheavyprecipitation,meltingsnow,orrunoffmaypose

problemsforallkindsofproperties.Olderandnewerhousesmaybeatrisk

forfloodingifproperprecautionsarenottaken.TheCityencouragesall

buildersandhomeownerstotakepreventivemeasurestoavoidflooding.This

bookletcontainsinformationon:

• Why homes flood

• Protecting your home from flooding

• Eavestroughs, downspouts and weeping tile

• Pipes, sump pumps and backwater valves

• Improving lot grading

• Maintaining your home drainage system

February 2010