Chapter 1-6 - Traffic Calming
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Traffic Calming 1.6‐1 SECTION 1, CHAPTER 6 Traffic Calming 6.1 Introduction 6.1.1 What is Traffic Calming? Traffic calming deals with neighborhood traffic issues comprehensively using the “three E’s,” Education, Enforcement, and Engineering, to slow or reduce motor vehicle traffic and improve safety for pedestrians and bicyclists. A fourth “E,” enhancement, is used to improve area aesthetics and soften the look of physical installations. Education provides neighbors with information about how they as motorists can help to ease traffic impacts in their community through changes in behavior and attitudes, and informs them about neighborhood traffic management activities and opportunities. Enforcement enlists the assistance of the Police Department to focus enforcement efforts in key areas. Engineering and planning encompasses both traditional traffic management measures as well as newer approaches, such as traffic calming. All three are important components in dealing effectively with neighborhood and community‐wide traffic issues. Modern traffic calming began as a grassroots movement in the late 1960’s which started with the Woonerf developments in the City of Delft, the Netherlands. Woonerven, or “living streets,” are residential streets where speeds are drastically reduced through reconstruction and space is shared between vehicles and pedestrians. According to the Institute of Transportation Engineers, traffic calming is the “combination of mainly physical measures that reduce the negative effects of motor vehicle use, alter driver behavior and improve conditions for non‐motorized street users.”
Transcript of Chapter 1-6 - Traffic Calming
Traffic Calming 1.6‐1
SECTION 1, CHAPTER 6
Traffic Calming
6.1 Introduction
6.1.1 What is Traffic Calming?
Trafficcalmingdealswithneighborhoodtrafficissuescomprehensivelyusingthe“threeE’s,”Education,Enforcement,andEngineering,tosloworreducemotorvehicletrafficandimprovesafetyforpedestriansandbicyclists.Afourth“E,”enhancement,isusedtoimproveareaaestheticsandsoftenthelookofphysicalinstallations.Educationprovidesneighborswithinformationabouthowtheyasmotoristscanhelptoeasetrafficimpactsintheircommunitythroughchangesinbehaviorandattitudes,andinformsthemaboutneighborhoodtrafficmanagementactivitiesandopportunities.EnforcementenliststheassistanceofthePoliceDepartmenttofocusenforcementeffortsinkeyareas.Engineeringandplanningencompassesbothtraditionaltrafficmanagementmeasuresaswellasnewerapproaches,suchastrafficcalming.Allthreeareimportantcomponentsindealingeffectivelywithneighborhoodandcommunity‐widetrafficissues.Moderntrafficcalmingbeganasagrassrootsmovementinthelate1960’swhichstartedwiththeWoonerfdevelopmentsintheCityofDelft,theNetherlands.Woonerven,or“livingstreets,”areresidentialstreetswherespeedsaredrasticallyreducedthroughreconstructionandspaceissharedbetweenvehiclesandpedestrians.
According to the Institute of Transportation Engineers, traffic calming is the “combination of mainly physical measures that reduce the negative effects of motor vehicle use, alter driver behavior and improve conditions for non‐motorized street users.”
1.6‐2 Traffic Calming
IntheUnitedStates,Seattle,Washingtonwasanearlypioneerinarea‐widetrafficcalmingwithneighborhood‐widedemonstrationsintheearly1970’s.Berkeley,CA,wasoneofthefirstcommunitiestoestablishacomprehensivearea‐wideprogramoftrafficcalming,whenitadoptedacitywidetrafficmanagementplanin1975.TheCityofNorwalkhasimplementedtrafficcalmingmeasuresinseveralneighborhoodsthroughouttheCityinrecentyears.Usinglessonslearnedfromtheseprojects,atrafficcalmingprogramwasdevelopedaspartoftheCity‐WideTrafficManagementPlan(TMP)toprovideaprocessforselectingappropriatetrafficcalmingmeasuresandprioritizingprojectfunding.Thetrafficcalmingprogramisaresident‐drivenprocessthatensuressafetyandlivabilityforallroadusers.TheNorwalkTrafficCalmingProgramisdiscussedinSection2‐3.
6.1.2 Goals and Benefits
Themaingoaloftrafficcalmingistoreducevehiclespeedsandcut‐throughvolumesthroughresidentialneighborhoods,providinglivableenvironmentsthataresafeforpedestriansandbicyclists.Reducedvehiclespeedscanmeanfewer,lessseverecollisions,especiallywhenanincidentinvolvesapedestrian.Desiredspeedstypicallyrangefrom15to30milesperhourinresidentialsettingsand20to35milesperhourincommercialsettings,withanappropriatedesignspeedselectedforeachlocationbasedonexistingoperatingspeedsandthedesiredcharacteristicsoftheroadwayenvironment.Whilethenegativeeffectsofautomobiletrafficcannotbecompletelyeliminated,trafficcalmingcanencourageautomobiledriverstooperatesafelyandwithincreasedconsiderationforotherroadusers.Benefitstopedestriansandbicyclistsinclude: Increaseddriverattentivenesstothepresenceofpedestriansandbicyclists
Increasedspaceforbicyclelanesandpedestrianfacilities
Bufferingfrommotorvehicletrafficbyuseoftrees,landscaping,parkedvehiclesandbicyclelanes.
Feweropportunitiesforpedestrian/vehicleconflictsInadditiontothebenefitsforroadusers,trafficcalminghastheaddedadvantageofreducednoiseandairpollution.
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6.1.3 How to Use the Traffic Calming Toolbox
Trafficcalmingisarelativelynewconcept,andmanypeopledonotknowaboutthewidevarietyoftoolsandstrategiesthatareavailabletotheircommunities.Thischapterservesasaresourceforresidentsandneighborhoodgroupsseekingtoeffectchangeintheircommunities.Itisalsointendedforusebydevelopersinordertosupporttheestablishmentofmorelivable,walkablecommunitiesinNorwalk.NorwalkresidentsandneighborhoodgroupsmayusetheTrafficCalmingToolboxtolearnaboutthevarioustrafficcalmingtoolsandresources,beginthinkingabouttheroadwayclassificationandcharacteristicsoftheirneighborhood,andcreateaplanforgarneringsupportfortrafficcalmingintheirneighborhood.ThestepsinvolvedintheNorwalkTrafficCalmingProgramarediscussedindetailinSection2,Chapter3.TheTrafficCalmingToolboxisaresourcefordevelopersseekingtocreatestreetswhicharelivableandaccessibletoallresidentsandtenants.ThematrixinAppendixisaquickreferencefordeterminingwhichtrafficcalmingmeasuresmaybeappropriateforagivenlocation,andtheStandardSpecificationsandDetailsintheAppendixareprovidedtoassistindesigningtrafficcalmingmeasures.
6.2 Traffic Calming Toolbox (The Nuts and Bolts)
ThefollowingpresentsasummaryofthevariousTier1andTier2trafficcalmingmeasureswhichmaybeimplementedintheCityofNorwalk.Atrafficcalmingsummarymatrixoutliningthecost,bestuseandotherconsiderationsforthesetoolsisprovidedinAppendix.
6.2.1 Tier 1 Measures
ThefollowingTier1implementationmeasuresarelowcosttools,intendedtorespondquicklytoneighborhoodtrafficconcerns.Theyconsistofprimarilyeducation,enforcementandsomeengineeringmeasures.
6.2.1.1 Education
Theprimarypurposeofeducationinitiativesistoprovideinformationthatincreasesdriverawarenessandmotivatespeopletoaltertheirbehavior.
Pros::Inexpensive,somewhateffectiveonhigh‐volumecollectorsandarterials~wheretraditionalengineeringmeasuresarerestrictive.Cons::Littleevidencethatlong‐termbenefitscanbeachieved.
1.6‐4 Traffic Calming
6.2.1.2 Neighborhood Newsletter
Thismailercontainsinformationabouttheneighborhood’ssafetyconcerns,explainstheresultsofspeedandvolumestudiesandrecommendswaystoslowtrafficintheneighborhood.Inaddition,trafficandpedestriansafetybasicsarecovered.
Pros::inexpensive,cantargetspecificresidents.Cons::Doesnotreachnon‐localtravelers,limitedevidencethatthisapproachcanbeeffective.
6.2.1.3 Radar Speed Display Sign
Thesesigns,whichmaybeportable,useradartoprovidemotoristswithanelectronicdisplay,alertingthemiftheyareexceedingacceptablespeeds.
Pros::speedscanbereducedbyupto25%1whenusedinshortperiodsoftimeandonlowvolumeroadways.Goodpublicrelationsforneighborhoods.Educationaltoolformotorists.Cons::Residualeffectsofspeedsignplacementarenegligiblewhenremoved.Long‐termplacementhasbeenmetwithmixedresults.
6.2.1.4 Signage
SignsmaybeinstalledwhereappropriateandinaccordancewiththeManualofUniformTrafficControlDevices(MUTCD).TheMUTCDhasestablishedspecificwarrantsforinstallationofStopSigns,includingmulti‐wayStopSigns.TheCityofNorwalkdoesnotinstall“Stop”signsforspeedcontrol.Speedlimitsignsareinstalledforschoolzones(20milesperhour)andatpointswheredriverstendtoenterneighborhoods.Thespeedlimitonresidentialstreetsis25milesperhour.Pedestriancrossing,schoolcrossing,andbikeroutesignsmayalsobeusedtowarnmotoristsofbicycleorpedestrianactivityandcanhelptoreducevehiclespeeds.
Pros::inexpensive,whencoupledwithEnforcement(seebelow),canbeeffectiveovertime.Increasesdriverawarenessalongcertainstreets.Cons::Unwarrantedand/orunjustifiedsignagecanleadtonon‐complianceandcreatesafetychallenges.Signageisnot‘self‐enforcing’.
6.2.1.5 Enforcement
Whenappropriate,theDPWwillworkwiththeNorwalkPoliceDepartmenttotargetspecificareasidentifiedduringthedatacollectionprocesstoenforcespeedlimitsand
1 T. Mazzella and D. Godfrey, “Building and Testing a customer Responsive Neighborhood Traffic Control Program”, in 1995 Compendium of Technical
Papers, ITE, Washington DC, 1995.
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othertrafficlawsinneighborhoods.Bysharingkeytrafficdata,officerscanfocustheirpatrolsonthetimesandplaceswherespeedingmostoftenoccurs.
Pros::Long‐termperiodicdaytimespeedenforcementoncertainproblemcorridorsmayresultindriverchangesovertime;Canbeusedinareasthatdonotqualifyforengineeringsolutionstotrafficchallenges;Targetsviolatorswithoutunnecessarilyimpactingnormaltrafficflow.Cons::Withoutlong‐termdedicationoflawenforcementpersonneltoaspecificcorridor,targetedenforcementhasbeenshowntobedisappointing.
6.2.1.6 Striping and On‐street Parking
Widetravellanesallowforfastervehiclespeeds.Narrowingthetravellanethroughtheuseofpavementmarkingscancreateasubtletrafficcalmingeffectwithoutintroducingphysicalbarriersthatmayslowdownemergencyresponsevehicles.Narrowinglanesthroughtheuseofpavementmarkingsmaybeachievedbycreatingwidershouldersorstripingforon‐streetparkingononeorbothsidesoftheroad.
Pros::Inexpensive.Easytoinstallandmodify,asneeded.Someexperienceshaveindicatedthatmodestspeedreductionscanbeachieved.Canalsoprovideforimprovedbicycleandpedestriansafety,ifproperlyimplemented.Cons::Studieshaveshownthatbybetterdefiningtravellanessometimeshasthereverseimpactandmayincreasespeedsoncertaincorridors.Mayreduceon‐streetparking.
6.2.1.7 Landscaping
Landscapingmaybeusedinconjunctionwithothertrafficcalmingmeasuressuchasmediansandislands,chicanes,andgatewayareastoenhancethepedestrianenvironmentwhilehelpingtoprovideaneighborhoodidentity.
Pros::Generallywellreceivedbythepublicinresidentialneighborhoods.Can,andshould,beusedinconjunctionwithothertrafficcalmingelementstosoftentheirappearance.Cons::Long‐termmaintenancecostsneedtobeconsidered.Carefulconsiderationtosightlinesandothersafetyelementsshouldalsobeplanned.
6.2.2 Tier 2 Measures
Whenpossible,theaimofTier2measuresshouldbetoinherentlyalterthestreetenvironmentinawaythatmakeslowerspeedsmorecomfortablefordriversand
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increasestheirawarenessofthepresenceofbicyclistsandpedestrians.Onlywhereothermeasuresarenotfeasibleshouldmoreintrusivedevicessuchasspeedhumpsandroadclosuresbeused.
6.2.2.1 Textured and Colored Pavement
Texturedandcoloredpavementsmaybeusedtoannounceentryintoatrafficcalmedarea.Materialssuchasbrick,cobbles,stampedconcreteandconcretepaversmaybeusedalongtheentireroadway,inlimitedsections,oralongthepavementedgestosignaltodriversthattheyareinapedestrianzone.
Pros::Changesthedriverperspectiveandcanbeeffectiveinalertingdriverstochangeinsetting.Texturedpavementcanslowdriversdown,muchlikecobblestoneswould.Cons::Long‐termmaintenancecostsneedtobeconsidered.Texturedpavementmaypresentdifficultiesforpedestrianandbicyclists,particularlyinwetconditions.
6.2.2.2 Traffic Circle
Raisedcircularislandsconstructedinthecenterofintersections.Thisdesignrequiresvehiclestokeeprightandtravelthroughtheintersectioninacounter‐clockwisedirectionaroundtheisland.Trafficcirclescanbeplacedatbothfour‐wayandthree‐wayintersections.
Pros::Slowstrafficasdriversapproachcircle;Improvesaccessfromsidestreet;Breaksupsightlinesonstraightstreets;changesthecontextofthestreetandcanmakethecorridormoreaestheticallypleasinginneighborhoodsettings.Cons::Introducespossibledriverconfusionastowhohastheright‐of‐way.Possibleimpactstolargevehiclesturningleft;Couldpotentiallyimpactemergencyresponsetimes;bicyclistsmustmergewithtrafficaroundtrafficcircle.
6.2.2.3 Modern Roundabout
Amodernroundaboutisalargeraisedcircularislandinstalledinthecenterofanintersection.Thedesignrequiresvehiclestoslowdownandnavigatearoundtheislandinacounter‐clockwisedirection.Unlikeatraditionaltrafficcircle,amodernroundaboutrequiresvehiclestoyieldtovehiclesalreadyinthe
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roundaboutandthegeometryisspecificallydesignedtorestrictspeeds.Modernroundaboutsmaybeusedinplaceoftrafficsignalsathighervolumeroads.
Pros::Slowstrafficasdriversapproachcircle;Improvesaccessfromsidestreet;Breaksupsightlinesonstraightstreets;changesthecontextofthestreetandcanmakethecorridormoreaestheticallypleasinginneighborhoodsettings.Cons::Mayrequirerightofwayfromadjacentproperties;Introducespossibledriverconfusionastowhohastheright‐of‐way;Couldpotentiallyimpactemergencyresponsetimes;bicyclistsmustmergewithtrafficaroundtrafficcircle.
6.2.2.4 Curb Extension
Alsoknownasbulb‐outs,curbextensionsextendthesidewalkorcurblineoutintotheparkingcrossingsbyreducingthepedestriancrossingdistance,visuallyandphysicallynarrowingtheroadway,improvingtheabilityofpedestriansandmotoriststoseeeachother,andreducingthetimethatpedestriansareinthestreet.
Pros::Pedestriancrossingdistancesarereduced;Narrowedroadwaysectioncancontributetoreducedspeeds;Breaksupdriversightlines;Introducesopportunityforlandscapingandvisualenhancementsfortheneighborhood.Cons::Mayreducevisibilityforbicyclists;Mayrequirelossofon‐streetparking;Expensivetoconstruct;Mayincreaseemergencyresponsetimes;caninterferewithsnowremovaloperations;Mayimpactdrainagealonggutterlines.
6.2.2.5 Edge Treatment
Edgetreatments,suchasraisedcurbs,provideuniformcrosssectionswithidentifiableedgesalonganentirecorridor.Theyoftensignalalowerdesignspeedtodrivers.Raisedcurbsalsoallowplacingroadsideobjectssuchastreesandstreetfurnitureclosertotheroadway,producingatrafficcalmingeffect.Wherecurbsareimpractical,pavementmarkingsorchangesinpavementtexturemaybeusedtocreateasimilareffect.
Pros::Mayslowtrafficalongcertaincorridors;Easytoinstall;Mayhavepositiveimpactonstormwatermanagement.Cons::Notself‐enforcing;Mayhavenegativeimpactonutilitiesandstormwatermanagementifnotproperlyconsidered.
6.2.2.6 Median Island
Raisedislandsplacedinthecenterofaroadwaytoseparateopposingtraffic.Theycanbeplacedmid‐blockoratentrancesintoneighborhoods.Mediansnarrowtheroadway,displacingavehicletotherightwhichtendstoslowtraffic.Thesecanbeovalor
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ellipticalshaped.Thoseislandsusedatacrosswalktoprovideapedestrianrefugeincreasepedestriansafetybyallowingpedestrianstocrossonedirectionoftrafficflowatatime.Typically,mediansarelandscapedtoprovidevisualenhancement.
Pros::Narrowedlanescanslowvehiclespeeds;Providesshorterdistancesincertaininstancesforpedestrianstocross;Opportunityforlandscapingandvisualenhancementstoneighborhood.Cons::MayinterruptdrivewayaccessandresultinU‐turnsattheendofmedians;Possiblelossofon‐streetparking;highcosttoconstruct;possibleimpacttostormwatermanagement;mayinterferewithsnowremovaloperations.
6.2.2.7 Gateway Treatment
Agatewayisaphysicalorgeometriclandmarkthatindicatesachangeinenvironmentfromahigherspeedarterialorcollectorroadtoalowerspeedresidentialorcommercialdistrict.Theyoftenplaceahigheremphasisonaestheticsandarefrequentlyusedtoidentifyneighborhoodandcommercialareaswithinalargerurbansetting.Gatewaysmaybeacombinationofstreetnarrowing,medians,signing,archways,roundabouts,orotheridentifiablefeatures.Gatewaysshouldsendaclearmessagetomotoriststhattheyhavereachedaspecificplaceandmustreducespeeds.
Pros::Alertsdriverstothetransitionfromhigh‐speedroadwaystolower‐speedsettings;Canbeaestheticallypleasingandbetterdefineneighborhoods.Mosteffectiveoninfrequentusersofthecorridor.Cons::Long‐termmaintenancecostsforlandscapingshouldbeconsidered;mayonlybeeffectiveinslowingdriversastheytransitionintoneighborhood;notshowntobeeffectiveforfrequentcommuters.
6.2.2.8 Chicane
Chicanesconsistofaseriesofcurbextensionsthatnarrowthestreetatselectedpointsandforcemotoriststoslowdowntomaneuverbetweenthem.TheyalternatefromonesideofthestreettotheothertoformS‐shapedcurves.Chicanescreateapark‐likeenvironmentandencourageadditionalgreeneryandplantings,butmustbedesignedcarefullytoavoiddriversfromdeviatingoutoftheappropriatelane.
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Pros::Mayslowdriversandreducecut‐throughtraffic;Changesthelookofthestreet;Hasminimalimpactonemergencyresponse.Cons::Requiresdesignandexpensiveimplementation;Likelytorequiremodificationstostormwaterdrainage;mayimpacton‐streetparking;mayimpactsnowremovaloperations;Withoutproperplanning,canhavelittletonoimpactoncut‐throughtraffic.
6.2.2.9 Choker or Neckdown
Chokersaresimilartocurbextensionsthatnarrowastreetbycreatingamid‐blockpinchpointalongthestreet.Chokerscanbecreatedbybringingbothcurbsin,orbyinstallingplantingstrips.Theycanbedonemoredramaticallybywideningonesideatamid‐blocklocation.Theycanalsobeusedatintersections,creatingagatewayeffectwhenenteringastreet.
Pros::Narrowedlanescanslowvehiclespeeds;Breaksupdriversightlines;Increasespedestrianandmotoristvisibility.Cons::Possiblelossofon‐streetparking;Narrowlanesdirectbicyclistsintovehiculartravellanes;Impactstostormwaterdrainage;highcosttoconstruct;mayimpactsnowremovaloperations.
6.2.2.10 Diverter or Partial Closure
Adiverterisanislandbuiltataresidentialstreetintersectionthatpreventscertainthroughand/orturningmovements.Partiallyorfullyclosingaccesstoaneighborhoodstreetwillcertainlyincreasetrafficonsurroundingstreets.Theseshouldbeusedasmeasuresoflastresortandonlyconsideredifotherlessrestrictivephysicalmeasureshavefailed.
Pros::Reducescut‐throughtraffic;Channelstrafficflow,thuseliminatingvehicularconflictsatsomeintersections;canbedesignedtoaccommodateemergency
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vehicles;presentsopportunitiesforlandscapingandvisualenhancementstoaneighborhoodsetting.Cons::Willredirecttraffictootherlocalstreets;causesincreasedtraveltimesforlocalresidents;highcosttoconstruct;isapermanentmeasurethatmayonlyaddressproblemsduringcertaintimesoftheday;mayrequireremovalofon‐streetparking;needssignificantwarningandguidancesignage;mayaffectsnowremovaloperations.
6.2.2.11 Reduced Corner Radii
Reducingthecurbradiiatanintersectionforcesdriverstoslowdowntomaketighterturns.Careshouldbetakenwhenusingthistrafficcalmingapproachasreducedradiicanlimittheturningmovementsoftrucks,busesandemergencyresponsevehicles.
Pros::Selfenforcing;potentiallyreducesthecrossingdistanceforpedestrians.Cons::Maynegativelyimpacttheabilityoflargevehiclestonegotiateturns;mayimpactemergencyresponsetimes.
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6.2.2.12 Roadway Closure
Afullroadwayclosurecompletelycutsofftraffictothroughvehicles,leavingonlypedestrianandbicycleaccess.Theseclosuresaretypicallyusedonlyasalastresortafterothertrafficcalmingmethodstoreducecut‐throughtraffichavefailed.Astreetmaybeclosedatanintersectionormid‐blockthroughtheuseofwalls,bollards,landscapedislands,orgatesthatallowemergencyvehicleaccess.
Pros::Selfenforcing;Restrictsallthroughtraffic;Effectiveatvolumeandspeedcontrol;MayImprovetheaestheticqualityofthestreet;Canallowforcontinuedpedestrianandbicycleflow,Cons::Mayredirectdriverstootherstreets;Highcosttoconstructandmaintain;couldresultinrightofwaytakingsastheabilityforvehiclestoturn‐aroundneedstobeprovided;Mayincreasetriplengthsfordrivers;mayimpacton‐streetparking;Impactstoemergencyresponseroutes.
6.2.2.13 Turn Restriction
Turnrestrictionscaninsomecasesbealow‐costmethodofreducingcut‐throughtraffic,buttheyrequireenforcement.
Pros::Inexpensive.Reducescutthroughtraffic;Effectiveatvolumeandspeedcontrol.Cons::Mayredirectdriverstootherstreets;Mayincreasetriplengthsfordrivers;
6.2.2.14 Speed Hump
Speedhumpsareraisedsectionsintheroadwayapproximately3incheshighattheircenterandextendingthefullwidthofthestreet,taperingnearthedrainguttertoallowunimpededbicycletravel.Thetraditionalhumprangesfrom14feetto22feetinlength.Thelongerhumps,alsoknownasspeedtables,aremuchgentlerforlargervehicles.Speedhumpsaretypicallyplaced200to600feetapart.Speedhumpsaredifferentthanspeedbumps,whicharecommonlyseeninparkinglotsoronprivatestreets.TheCityofNorwalkdoesnotallowspeedbumpsonpublicstreets.Speedhumpscanhelpcontrolspeedingandcutthroughtrafficonlocalneighborhoodstreets.
1.6‐12 Traffic Calming
Unliketraditionalpoliceenforcement,speedhumpsprovidecontinuousservice.Speedhumpsaremostusefulwhenspeedsareinexcessof35mphintheimmediatevicinityofthespeedhump.Theyarelesseffective,however,inbetweeninstallations.Speedhumpscanbeveryeffectiveifusedappropriately.Thereare,however,somenegativeimpactstheymayhave: Residentslivingnearspeedhumpsmusttolerateincreasednoiselevelsasvehicles
traversespeedhumpsdayandnight.
Vehiclesmaydriveonsidewalksorthroughfrontyardstoavoidspeedhumps.
Trafficmaybedivertedtootherstreetsintheneighborhood.
Police,fireandemergencymedicalserviceresponsetimessuffer.
Motorizedstreetsweepingequipmentcannotbeusedatspeedhumplocations.
Speedhumpsinterferewithstreetrepaving,decreasingtheeffectivenessofboththespeedhumpandthenewpavementsurface.
Speedhumpsblocktheflowofdrainagewateronsomestreetsandcancausefloodingproblems.
Speedhumpsrequiresigningandstriping,whichsomeresidentsconsiderunattractive.
Pros::Selfenforcing;Maydecreasetrafficvolumes;requiresminimalmaintenance.Cons::Likelytoincreasenoiseinthevicinityofthehump;potentialtoimpactdrainage;mayincreaseemergencyresponsetimes;difficulttoreplace.
6.2.2.15 Raised Intersection
Araisedintersectionisessentiallyaspeedtablefortheentireintersection.Constructioninvolvesprovidingrampsoneachvehicleapproach,whichelevatestheentireintersectiontothelevelofthesidewalk.Theycanbebuiltwithavarietyofmaterials,includingasphalt,concrete,stampedconcrete,orpavers.Thecrosswalksoneachapproacharealsoelevatedaspartofthetreatmenttoenablepedestrianstocrosstheroadatthesamelevelasthesidewalk,eliminatingtheneedforcurbramps.
Pros::Selfenforcing;Providesclearcrossinglocationforpedestrians;Increasesdriverawareness.Cons::Likelytoincreasenoiseinthevicinityoftheintersection;potentialtoimpactdrainage;mayincreaseemergencyresponsetimes;difficulttoreplace;mayimpactsnowremovaloperations.
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6.2.2.16 Raised Crosswalk
Araisedpedestriancrossingisalsoessentiallyaspeedtable,withaflatportionthewidthofacrosswalk,usually10to15ft.Raisedintersectionsandcrosswalksencouragemotoriststoyield.
Pros::Selfenforcing;Maydecreasetrafficvolumes;requiresminimalmaintenance.Cons::Likelytoincreasenoiseinthevicinityofthecrosswalk;potentialtoimpactdrainage;mayincreaseemergencyresponsetimes;difficulttoreplace;mayimpactsnowremovaloperations.
