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LANDSCAPEANDURBANPLANNINGELSEVIERLandscapeandUrbanPlanning33(1995)47-64Fromgreenbelttogreenways:fourCanadiancasestudiesJamesTaylor*,CeceliaPaine,JohnFitzGibbonSchoolofLandscapeArchitecture,UniversityofGuelph,Guelph,Ont.NIG2W1,CanadaAbstractGreenwayshaveplayedasignificantroleinthedevelopmentofurbanareasinCanadaoverthepast40years.ThispaperpresentscasestudiesofurbangreenwaysystemslocatedinfourmetropolitanareasinCanada:theNationalCapitalRegioninOttawa,Ontario;Calgary,Alberta;Saskatoon,Saskatchewan;Toronto,Ontario.Aprofileofeachgreenwayispresenteddescribingthebackgroundoftheprojectanditsgeographiccontext,theplanningapproachused,theconceptunderlyingthedevelopmentplan,theadoptedadministrativeframework,thestructureoflandusecontrolmechanisms,andadiscussionoftheoutcomesoftheimplementationofeachplan.ThesefourcasestudiesrepresentsignificantexamplesofurbangreenwayplanninginCanada.Althoughthescope,planningmethods,form,andadministrativeframeworkforeachgreenwaydiffer,theyhavecommoncharacteristicsoflinearity,openspaceconservation,andconnectivityofurbanareastonaturalandruralenvironments.Collectivelytheseexamplesdemonstrateanevolutionfromanurbandesignapproachthatattemptedtoimposebothlandscapeformandlandusefunction,toanecologicallybasedplanningapproachthataddressesnaturalfactors,connectionsbetweennaturalandurbansystems,publicparticipationandsupport,andinnovativegovernmentinvolvement.Keywords:Greenways;Openspaceplanning;Urbanopenspace;Canadianlandscapeplanning1.IntroductionTheconceptoflinkedparksorgreenwaysinNorthAmericadatesbacktothenineteenthcentury(Little,1990).InCanada,themosttangibleexamplesofgreen-waysinurbanareashavebeendevelopedinthepast40years.ThispaperpresentscasestudiesofurbangreenwaysystemslocatedinfourmetropolitanareasinCanadathathavebeendevelopedfrom1950tothepresent.ThesystemsincludedareinOttawa,Ontario;Calgary,Alberta;Saskatoon,Saskatchewan;Toronto,Ontario(Fig.1).TheOttawa,Calgary,andSaskatoonsystemshavebeengenerallyrealizedasoriginallyenvisionedandthe*Correspondingauthor.Telephone:[phone],ext.3352.Fax:[phone]-2046/95/$09.5001995ElsevierScienceB.V.AllrightsreservedSsDrO169-2046(94)02013-2Fig.1.Locationmap.48J.Tayloretal./LandscapeandUrbanPlanning33(1995)47-44qExistingUrbanAreasRideau_qGreenbeltF3arrtlavenSC.:,KmIOFig.2.NationalCapitalGreenbelt,Ottawa,Ont.Fig.3.AerialviewoftheNationalCapitalGreenbelt.Photocredit:NationalCapitalCommission.Fig.4.AgriculturallanduseintheNationalCapitalGreenbelt.Photocredit:NationalCapitalCommission.Torontoexampleisbeingimplementedatpresent.TheseexamplesprovideanexcellentresourcefromwhichtoobservetrendsinplanningandtodevelopanunderstandingofthefactorscontributingtoboththesuccessesandfailuresofCanadiangreenwaysystems.2.TheNationalCapitalGreenbelt2.1.ProjectcontextInthelate194Os,PrimeMinisterMackenzieKingdirectedhisattentiontoformalizingacomprehensiveplanfortheCapitalofCanada,Ottawa-Hull.JacquesGreber,awell-knownFrencharchitect-planner,wascommissionedtoundertaketheproject.WorkingwithprofessionalstaffoftheFederalDistrictCommission,GrebercompletedtheplanfortheCapitalin1950.OneofthemostsignificantelementsoftheGreberplanwastheproposaltoestablishagreenzonearoundtheOttawaportionoftheNationalCapitalRegion(NCR).Thisarea,commonlyreferredtoasthe‘Green-belt’,is20000ha(50000acres)insize,hasanaver-agewidthof4km(2.5miles),andisover40km(25miles)inlength(Figs.2,3and4).PartsoftheGreen-beltareonly8km(5miles)fromParliamentHill,thegeographiccenterofthemetropolitanregion,andalmost500000peopleatpresentlivewithinitslimits(Scott,1992).TheOttawaGreenbeltissituatedwithintheGreatLakes-St.LawrencebioregiononrelativelyflatlandthatwasoncepartoftheChamplainSea.Soilsarecomposedofclayandsand,withimperfectdrainageandbedrockclosetothesurface.AlthoughpartsofthepresentGreenbelthavebeenreforestedwithintroducedspecies,nativeforestcoverremainsinsomeareas,con-sistingofmixedhardwoodsandconifersonbetter-drainedsoils,withcedar(Thujaoccidentalis),spruce(Piceaglauca)andtamarack(Z.&Xlaricina)inthepoorlydrainedareas.2.2.PlanningapproachPlanningfortheNCRusedacomprehensiveapproachbasedonpopulationprojections,analysisofexistingurbandevelopmentandassociatedinfrastruc-ture,andassessmentofthebiophysicallandscape(Gre-ber,1950,b).TheformandintentoftheOttawaGreenbeltwassimilartothe‘beltofgreen’conceptasproposedbyEbenezerHoward(Howard,1898)andJ.Tayloretal./LandscapeandUrbanPlanning33(1995)47-6449assubsequentlydevelopedsurroundingLondonandothercommunitiesinEngland.ThefinalboundariesfortheGreenbeltreflectedGreber’svisionofurbanform.Althoughfragmentsofnaturalareaswereincluded,naturalsystemsdidnotprovidetheframeworkordefinetheshapeoftheGreenbelt.ThespecificpurposesoftheOttawaGreenbeltwerethreefold.First,theGreenbeltwasintendedtopreventfurtherurbansprawlandtoprotectadjacentagriculturallandsfrombeingdeveloped.Second,theGreenbeltwasintendedtoprovideareserveofbuildingsitesforfuturegovernmentandpublicinstitutionaluse,oncethecen-tralareaofOttawawasbuiltup.Third,theGreenbeltwasintendedtoplacea‘practicalandeconomic’limitonthegrowthoftheCa