FREQUENTLY ASKED QUESTIONSPermittingIs rainwater harvesting legal in San Francisco?
Yes! San Francisco residents can legally use rainwater for non-potable purposes such as irrigation and •toiletflushing.
What is the permitting process to install a rainwater harvesting system? For aCistern: To install a cistern for irrigationor toilet flushing, youwill needaplumbingpermit anda•buildingpermitfromtheDepartmentofBuildingInspection(DBI).Ifyoursystemincludesapumporwillbeinstalledontherooforunderground,youwillneedadditionalpermits.Formoredetails,seeourRainwaterHarvesting MOU at http://stormwater.sfwater.org.ClickontheRainwaterHarvestingicon.
ForaRainBarrel:ThePublicUtilitiesCommission,theDepartmentofPublicHealth,andtheDepartmentof•Building Inspection are in the process of developing a permitting procedure for rainwater harvesting with rainbarrels.
System Design, Sizing and InstallationIsthereabrochuredescribingwhatrainwaterharvestingisandwhyitisbeneficial?
Yes!Pleaseexploreourwebsiteat• http://stormwater.sfwater.org.ClickontheRainwaterHarvestingicontoviewordownloadourbrochures,rainbarrelinstallationguide,factsheets,andvideolinks.
How do I determine the size cistern or the number of barrels I need?Thesizeofyoursystemdependsonanumberoffactors:howbigyourroofis,howmuchspaceyouhave•availableforrainwaterstorage,andwhatyouintendtousethewaterfor.Aroughruleofthumbisthatyoucancollect600gallonsofwaterforevery1,000squarefeetofroofareaforeveryinchofrain.Wegetanaverageof21inchesofrainperyearhereinSanFrancisco,sofor1,000squarefeetofroofthatcanadduptoover12,000gallonsofrainwatercollected!Youwillhavetocarefullyplanwheretherainwaterwillgowhenitoverflows.Youmaydirectittoanapproveddrainorstormwatermanagementfacilitysuchasaraingarden.
DoestheSFPUChaveacistern-sizingcalculator?OurRainwaterHarvestingCalculatorisonitsway!Pleasecheckourwebsiteoftenforupdates.Go•to http://stormwater.sfwater.organdclickonRainwaterHarvesting,orbecomeafanoftheSF Urban Watershedspageonfacebook!
Whathappenswhenmyrainbarreloverflows?Youmaydirecttheoverflowbacktothesewerviaanapproveddrain,ordesignaraingardento•accommodatetheoverflow.Eachsiteisdifferent,sodifferentdesignsolutionsarecalledforindifferentplaces.
Do I need gutter screens if I have a “do-it-yourself” 60 gallon barrel? Yes,gutterscreenspreventdebrisfromenteringyoursystemandmakeyourmaintenanceactivities•muchsimpler.Ourrainwaterharvestingbrochureandhow-toflierformakingyourownrainbarrelprovidealistofpartsforinstallingrainbarrelsystems.Remember,propersystemdesign,maintenanceandusearetheresponsibilityofthesystemowner,nottheSanFranciscoPublicUtilitiesCommission(SFPUC),theSFDepartmentofBuildingInspection(DBI),ortheSFDepartmentofPublicHealth(DPH).
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rainwater harvestingS A N F R A N C I S C O P U B L I C U T I L I T I E S C O M M I S S I O N
WhatextrastepsdoIneedtotakeifIwanttouserainwaterfortoiletflushing?TheSFPUC,DPH,andDBIhaveagreedtoallowtheuseofrainwaterfortoiletflushingandirrigation.To•readaboutrulesregardingflushingyourtoiletswithrainwater,seetheinteragencyRainwaterHarvestingMOU at http://stormwater.sfwater.org.ClickontheRainwaterHarvestingicon.
System Operation & MaintenanceHow long can I hold rainwater in my barrel or cistern? What are the sanitary precautions I must follow?
Aslongasyourrainwaterharvestingsystemisopaque(ofsuchcolorandthicknessthatsunlightcannot•penetratethebarrel),shaded,andscreened,andyouusethewateronlyfornon-potablepurposes,thereisnostrictlimitonhowlongthewatercansitinyoursystem.Besuretoinspectyoursystemoftenandcleanitasneeded.Youcancleanyoursystemannuallywithanon-toxiccleanersuchasvinegar.Ifyouintendtowateredibleswithyourrainwater,youmustinstallafirstflushdiverter,whichwillensurethatyouharvestonlythecleanestrainwater.
Will my rainwater system run out of water during the dry months?
Itdependsonthesizeofyoursystem.Ifyouhaveenough•space to accommodate a large cistern and your water needsarelow,yourcatchmentsystemcouldholdrainwaterforallyoursummerneeds.Ifyouareusingasmallrainwaterharvestingsystem,therainwaterwillrunoutquickly.Italldependsonthedesign.Evenifyoursystemrunsdryinthesummer,ifyouareabletoflushtoilets all winter long and then switch to the municipal supplyinthesummer,that’sstillagoodachievement.Anecdotally,alocalSFrainharvesterhasreportedcapturing60gallonsofwaterfromasummer’sworthoffogandcondensationfromherGalvalumeroof!
Cost & AvailabilityHow much do rain barrels and cisterns cost? How much would an entire rainwater harvesting system cost?
Pricesrangewiththescaleanddesignofyourprojectandwiththeamountofresearchandassembly•youarewillingtodoyourself.Youcanfindbarrelsranginginpriceanywherefrom$15to$100,ormore,dependingondesign,material,brand,andsupplier.Sometimespeoplegiveawaybarrelsforfreesotheydon’thavetopaydisposalfees!Foracistern,manypeopleusetheruleofthumbof$1pergallonofstorage.Thisdoesnotincludeshipping,installation,oranyadditionalplumbingandwillvarydependingondesign,material,brand,andsupplier.
WherecanIfindrainbarrelsandcisterns?Aretherelocalbusinessesthatcarrythem?Belowisalistofsuppliersandproducts.Thisisabriefsamplelisttogetyoustarted–therearenumerous•additionalproductsyoucanfindonline.This list is for information only and does not imply SFPUC endorsement:
BushmanRainwaterHarvestingProducts: ◦www.bushmanusa.com/pdfs/BushmanRainwaterHarvesting.pdf
ColeHardware,SanFrancisco: ◦ www.colehardware.com
FairfaxLumber: ◦ www.fairfaxlumber.com
NationalStorageTank,SantaRosa,CA: ◦ www.nationalstoragetank.com
RainwaterH ◦ 2OG:888.700.1096, http://rainwaterhog.com
ScottsValleySprinklers:831.438.6450, ◦ www.svsprinklerandpipe.com
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UrbanFarmerStore,SanFrancisco:415.661.2204, ◦ www.urbanfarmerstore.com
Watertanks.com,Windsor,CA: ◦ www.watertanks.com
WATERHARVESTSLIMLINE: ◦ www.bluescopewaterusa.com/go/tank-products/waterharvest-urban-rainwater-tanks
Youcanalsomakeyourown!Youcanusuallyfindbarrelsatverylow•prices at www.craigslist.org.Youcanusesearchtermslike“rainbarrel,”“foodgradebarrel,”“plasticbarrel,”or“metaldrum”tofindtheposts.Youwillhavetopurchaseandassemblethepartsyourself,butifyouarethehandytype,itshouldn’tbeaproblem.CheckoutourRainwaterHarvestingBrochures,InstallationInstructions,andinstallationvideoonourwebsiteathttp://stormwater.sfwater.org.
ManyofthepartsneededtomakeyourownrainbarrelsystemareavailableattheUrbanFarmerStore•(www.urbanfarmerstore.com)
Youcanfindamoreextensivelistofproductsandsuppliersat• www.harvestingrainwater.com/rainwater-harvesting-inforesources/suppliers/
Doesthecityofferrebates,incentives,orsubsidiesforrainwaterharvestingsystems?TheUrbanWatershedManagementProgramrecentlycompletedasuccessfulsubsidyprograminwhich•theSFPUCsubsidizedfullyequippedrainbarrelsforSanFranciscoresidents.Eachbarrelwasretailedfor$120andtheSFPUCoffereda$50-discountperbarrel.Staffisinvestigatingthepossibilityofdoingtheprogramagainthisfall.
YoucanapplyforaCommunityChallengeGrantifyourrainwaterharvestingprojectbenefitsthepublic•realm(privatehomeinstallationswillnotqualify).ViewtheCCGprogramapplicationguidelinesatwww.sfgov.org/site/uploadedfiles/ccg/CCGApplicationGuidelines.pdf.
How much can I save by harvesting rainwater?ArecentanalysisbytheSFExaminerfoundthatanaveragehouseinthecitycansavealmost$200on•theirwaterbilleveryyeariftheycollectalltherainwaterfallingontheirroof.Checkoutthearticleat:www.sfexaminer.com/local/When_rainy_weather_arrives_its_harvest_season.html
Resources & Continued EducationWherecanItakeacourseorlearnmoreaboutrainwatercaptureanduse?
AmericanRainwaterCatchmentSystemsAssociation:• www.arcsa.org
For plumbers: • www.greenplumbersusa.com/training-accreditation/course-information#caringforourwater
TheOccidentalArtsandEcologyCenter:• www.oaecwater.org
RainwaterHarvestingforDrylandsandBeyond• ,Volumes1and2.BradLancaster,2008edition.www.harvestingrainwater.com
DesignforWater:RainwaterHarvesting,StormwaterCatchment,andAlternateWaterReuse• .HeatherKinkade-Levario,2007.
Dig Cooperative: • http://dig.coop
TheGreywaterGuerrillas:• www.greywaterguerrillas.com
RehbeinEnvironmentalSolutions,Inc:• www.rehbeinsolutions.com
NSF-certifiedrainwaterharvestingproducts:• www.nsf.org/consumer/rainwater_collection/index.asp?program=RainwaterCol
Visit the • SF Urban Watershedsfacebookpageandbecomeafan!
Visit the SF Sewers Blog at • sfsewers.blogspot.com andviewourRainBarrelInstallationVideo
Join the • RainHarvesterfacebookgroup!
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How are other places encouraging rainwater harvesting?PaloAlto,CA:• www.cityofpaloalto.org/depts/pwd/flood_+_storm/stormwater_rebates/cisterns.asp
Portland,OR:• www.portlandonline.com/osd/index.cfm?c=ecbbd&a=bbehfa and www.portlandonline.com/bes/index.cfm?c=41186
SantaRosa,CA:• http://ci.santa-rosa.ca.us/doclib/Documents/RainwaterRebateInfoFAQs.pdf
Seattle,Washington:• www.seattle.gov/UTIL/Services/Yard/Natural_Lawn_&_Garden_Care/Rain_Water_Harvesting/index.asp
Texaspassedstate-widelegislationencouragingrainwaterharvestingthroughpropertytaxexemptions•and is on its third edition rainwater harvesting manual: www.twdb.state.tx.us/publications/reports/RainwaterHarvestingManual_3rdedition.pdf
Tucson,Arizona:• www.ci.tucson.az.us/water/harvesting.html
Australia:• www.yourhome.gov.au/technical/fs73.html
Victoria: ◦ www.ourwater.vic.gov.au/saving/home/rainwater
Queensland: ◦ www.nrw.qld.gov.au/water/waterwise/pdf/rainwater_tanks.pdf
New South Wales: ◦ www.environment.nsw.gov.au/rebates/ccfrtw.html
SouthAustralia: ◦ www.sawater.com.au/sawater
InGermanyabout50,000newrainwaterharvestingsystemsareinstalledeachyear!TheGerman•AssociationforWaterRecyclingandRainwaterUtilization:www.fbr.de/english0.html
LearnaboutIndia’srainwaterharvestingprograms:• www.rainwaterharvesting.org
TheUKRainwaterHarvestingAssociation:• www.ukrha.org
AndForInspiration:www.youtube.com/watch?v=4xtMnE9Bo6s
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AdaisychainedsystemattheSFPUC’sSoutheastPlant.
