Traffic Calming: Introduction and Applications June 21st, 2007 by Indraneel Kumar, AICP Transportation Planning and Traffic Calming- Part 2

3 Es- Education, Enforcement, and Engineering Police enforcement-engineering options- street closure Management of traffic by volume and speed Part of “Context Sensitive Design” Flexible design standardsIntroduction What is Traffic Calming? Several definitions- ITE, VTPI, Source: VTPI.org

History 1960s first experiment commenced in Holland 1970s- Implementation in Germany (Verkehrsberuhigung or Transportation Calming) 1980s- Livable Streets by Appleyard, UC Berkeley Institute of Transportation Engineer’s Guidebook 1990s- Traffic Calming: State of the Practice, Reid Ewing, ITE Thousands of Traffic Calming projects Control Speed; Control Volume; Control Volume / Speed

Applications: Traffic Calming to Control Speed Bulb-Outs/ Curb Extensions/ Neckdowns Bulbs, Chokers, Neckdowns are interchangeable terms Bulbs, Chokers, Neckdowns are interchangeable terms Extension of the curb and sidewalk to narrow the roadway Extension of the curb and sidewalk to narrow the roadway Physical constraint Physical constraint Visual traffic calming effects Visual traffic calming effects Pedestrian crossing Pedestrian crossing Source: / Dan Burdenwww.pedbikeimages.org Source: / Dan Burdenwww.pedbikeimages.org Bulb-Out

Extension of the curb and plantingExtension of the curb and planting Midblock or intersection cornersMidblock or intersection corners Parallel, angled chokers, etc. Parallel, angled chokers, etc. Planting to alert the motorist Planting to alert the motorist Physical constraint Physical constraint Visual traffic calming effects Visual traffic calming effects Source: Making Streets That Work Choker Applications: Traffic Calming to Control Speed Chokers Source: / Dan Burdenwww.pedbikeimages.org Source: / Michael Kingwww.pedbikeimages.org

Applications: Traffic Calming to Control Speed Chicanes- staggered curves Chicanes- staggered curves Alternate extension of the curb Alternate extension of the curb Shift in alignment Shift in alignment Physical constraint Physical constraint Visual traffic calming effects Visual traffic calming effects Chicanes Source: ITE Source: / Michael Kingwww.pedbikeimages.org Source: / Portlandwww.pedbikeimages.org Source: / Portland Office of Transportationwww.pedbikeimages.org

Applications: Traffic Calming to Control Speed Speed Tables, and Cushions Source: / Dan Burdenwww.pedbikeimages.org Source: / Mark Lavergnewww.pedbikeimages.org Source: / Michael Kingwww.pedbikeimages.org Cushions- Convenient for emergency vehicles Cushions- Convenient for emergency vehicles

Applications: Traffic Calming to Control Speed Speed Bumps and Humps Source: PCRD / Kumar

Curb Radius, Raised Crossings and Intersections Source: / City of Portlandwww.pedbikeimages.org Source: / Dan Burdenwww.pedbikeimages.org Source: / Peter Lagerwaywww.pedbikeimages.org Applications: Traffic Calming to Control Speed Tighter curb radius Tighter curb radius Raised crossing and intersection- alerts drivers Raised crossing and intersection- alerts drivers Paving treatment + Raised surfaces Paving treatment + Raised surfaces Visual traffic calming effects Visual traffic calming effects

Applications: Traffic Calming to Control Speed Paving Treatments Source: / Dan Burdenwww.pedbikeimages.org Source: / Dan Burdenwww.pedbikeimages.org Source: / Dan Burdenwww.pedbikeimages.org Delineate users Delineate users Visual traffic calming effects Visual traffic calming effects

Applications: Traffic Calming to Control Speed Paving Treatments Source: PCRD / Kumar Source: / Dan Burdenwww.pedbikeimages.org Delineate the edge Delineate the edge ADA Guidelines ADA Guidelines Visual traffic calming effects Visual traffic calming effects

Applications: Traffic Calming to Control Volume Diverters, Partial Street Closures Source: / Dan Burdenwww.pedbikeimages.orgSource: / Dan Burdenwww.pedbikeimages.org Diagonal diverters create two unconnected streets- intersection Diagonal diverters create two unconnected streets- intersection Partial closure for motorized traffic Partial closure for motorized traffic Source: Delaware DOT

Applications: Traffic Calming to Control Volume Full Street Closures Full closures- reroute the traffic Full closures- reroute the traffic Partial/ Full closures and diverters are used to retrofit neighborhoods for traffic calming Partial/ Full closures and diverters are used to retrofit neighborhoods for traffic calming Source: PCRD / Kumar

Gateways, Lane Reduction Applications: Traffic Calming to Control Volume/Speed Source: / Dan Burdenwww.pedbikeimages.org Source: / Michael Cyneckiwww.pedbikeimages.org Lane reduction is also known as road diets; lane narrowing- visual traffic calming Lane reduction is also known as road diets; lane narrowing- visual traffic calming Gateways- visual traffic calming Gateways- visual traffic calming Source: PCRD / Kumar

Refuge Islands, Roundabouts / Traffic Circles Applications: Traffic Calming to Control Volume/Speed Source: / Dan Burdenwww.pedbikeimages.org Source: / Dan Burdenwww.pedbikeimages.org Roundabouts are popular techniques Roundabouts are popular techniques Comprehensive traffic management plan / retrofit Comprehensive traffic management plan / retrofit

Applications: Traffic Calming Traditional Neighborhood / Narrow Streets Congress for the New Urbanism Congress for the New Urbanism Wider street standards are giving way to narrower streets, particularly in residential areas Wider street standards are giving way to narrower streets, particularly in residential areas More asphalt = More vehicles More asphalt = More vehicles Source: / Dan Burdenwww.pedbikeimages.org A grassroots effort for narrow street standards is happening A grassroots effort for narrow street standards is happening Source: FHWA

Applications: Traffic Calming- Streets for Living Woonerf Streets designed to be shared by pedestrians, motorists, and the community Streets designed to be shared by pedestrians, motorists, and the community Sidewalks, planters, benches are merged into the street Sidewalks, planters, benches are merged into the street Physical constraints Physical constraints Speed < 10 miles per hour Speed < 10 miles per hour Public realm Public realm Higher costs Higher costs Emergency vehicles ? Emergency vehicles ? Source: Maricopa County Government

Travel Impacts- Pre and post Traffic Calming travel impacts- motorized / non motorized travel Pre and post Traffic Calming travel impacts- motorized / non motorized travel Assumption % increase in non motorized travel- half of that substitute motorized travel Assumption % increase in non motorized travel- half of that substitute motorized travel Traffic Calming Impacts- Benefits and Costs Advocates- Traffic Calming protects residents, bicyclists, and pedestrians Traffic Calming protects residents, bicyclists, and pedestrians Multiple and safe use of the street Multiple and safe use of the street Critics- Waste of resources Waste of resources Shifts the traffic problems from one to another street Shifts the traffic problems from one to another street Source: Todd Litman; Traffic Calming: Benefits, Costs, and Equity Impacts; Calgary health regionwww.VTPI.org

Traffic Calming Impacts- Benefits Increased Safety Increased Safety # Significant reduction in accidents # Payback through lives, injuries, and insurance savings Increased non motorized and decreased motorized travel Increased non motorized and decreased motorized travel # Less noise and air pollution; health benefits; parking & gas savings, etc. Source: Todd Litman; Traffic Calming: Benefits, Costs, and Equity Impacts; Fatal

Traffic Calming Impacts- Benefits and Costs Benefits….. Increased public realm, interaction and crime prevention- Crime Prevention Through Environmental Design (CPTED)Increased public realm, interaction and crime prevention- Crime Prevention Through Environmental Design (CPTED) Defensible Space by Oscar Newman Defensible Space by Oscar Newman Increased property values Increased property values Source: Todd Litman; Traffic Calming: Benefits, Costs, and Equity Impacts; Costs Project expenses Project expenses Liability claims Liability claims Vehicle delays Vehicle delays Traffic spill to other roads Traffic spill to other roads Problems for emergency and service vehicles Problems for emergency and service vehicles Driver frustration Driver frustration Problems for bicyclists and visually impaired Problems for bicyclists and visually impaired

Traffic Calming Impacts- Horizontal vs. Vertical Equity Equity is important in Transportation Planning Equity is important in Transportation Planning Horizontal equity is distribution of benefits and costs within groups similar in income, wealth, and ability Horizontal equity is distribution of benefits and costs within groups similar in income, wealth, and ability Vertical equity is distribution of benefits and costs within groups dissimilar in income, wealth, and ability Vertical equity is distribution of benefits and costs within groups dissimilar in income, wealth, and ability A better balancing of different uses of the street- motorists, cyclists, pedestrians, residents A better balancing of different uses of the street- motorists, cyclists, pedestrians, residents Increased safety for pedestrians, cyclists, residents, and transit users Increased safety for pedestrians, cyclists, residents, and transit users Source: Todd Litman; Traffic Calming: Benefits, Costs, and Equity Impacts;

Traffic Calming – Planning Process Public / residents must be involved from the beginning (neighborhood-wide traffic management) Public / residents must be involved from the beginning (neighborhood-wide traffic management) Residents petition for traffic calming (street-wide) Residents petition for traffic calming (street-wide) Public Works or Engineering Department propose- traffic calming strategies and devices Public Works or Engineering Department propose- traffic calming strategies and devices Community acceptance is essential Community acceptance is essential Traffic calming device is put on place Traffic calming device is put on place Project evaluation Project evaluation Traffic calming device is made permanent Traffic calming device is made permanent

Traffic Calming- Sources (Traffic Calming: State of the Practice) (Traffic Calming: PAS 456)

Thank you!!!