The Homeowner’s Guide to Flood Prevention
HOW TO IDENTIFY PROBLEMS & MAINTAIN YOUR HOME’S DRAINAGE SYSTEMS
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
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.
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*)
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
*
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
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.
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
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.
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.
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
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.
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.
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”
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
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.
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.
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.
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.
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.
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.
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.
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
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.
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.
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.
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.
The Homeowner’s Guide to Flood Prevention26
Do-it-yourselfResources
Ifyouplanondoingtheworkyourself,youcangetalotofsupportandinformationfromhardware,homeimprovementandplumbingsupplystores.Manyofthestaffaretradeprofessionalsandareusuallymorethanhappytosharetheirknowledgeandexpertisewithyou.
AlbertaHealthServices 780-735-1800
Leakyorfloodedbasementsmaybecomeahealthriskifclean-upisnotdonequicklyandcorrectly.Thisenvironmentalhealthservicesunitcanprovideinformationandadviceinresponsetoinquiriesaboutpotentialhealthrisks.
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.
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.
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.
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