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Case Study:Mini-Roundabout in anUrban SettingDept. of Public WorksHarford County Gov’t, Maryland

Case Study:Mini-Roundabout in anUrban SettingDept. of Public WorksHarford County Gov’t, Maryland

Jeff StratmeyerChief Engineer

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Just what is a mini??

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Mini-Roundabout

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So why a mini-roundabout & what’s different about it?

So why a mini-roundabout & what’s different about it?

• First the “Why”….

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So why a mini-roundabout & what’s different about it?

• First the “Why”….▫ Background

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Tollgate Rd. & Marketplace Dr.1996

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So why a mini-roundabout & what’s different about it?

• First the “Why”….▫ Background▫ Need for traffic control

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So why a mini-roundabout & what’s different about it?

• First the “Why”….▫ Background▫ Need for traffic control▫ Significant Problem

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Law Department: “No”

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So why a mini-roundabout & what’s different about it?

• First the “Why”….▫ Background▫ Need for traffic control▫ Significant Problem

• Second…the “What”

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So why a mini-roundabout & what’s different about it?

• First the “Why”….▫ Background▫ Need for traffic control▫ Significant Problem

• Second…the “What”▫ “Still” a roundabout – with all applicable traffic rules

So why a mini-roundabout & what’s different about it?

• First the “Why”….▫ Background▫ Need for traffic control▫ Significant Problem

• Second…the “What”▫ “Still” a roundabout – with all applicable traffic rules▫ Size: 50’ – 90’ diameter

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So why a mini-roundabout & what’s different about it?

• First the “Why”….▫ Background▫ Need for traffic control▫ Significant Problem

• Second…the “What”▫ “Still” a roundabout – with all applicable traffic rules▫ Size: 50’ – 80’ diameter▫ Fully mountable central & splitter islands

So why a mini-roundabout & what’s different about it?

• First the “Why”….▫ Background▫ Need for traffic control▫ Significant Problem

• Second…the “What”▫ “Still” a roundabout – with all applicable traffic rules▫ Size: 50’ – 80’ diameter▫ Fully mountable central & splitter islands Generally no higher than 4-5” – but clearly visible

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So why a mini-roundabout & what’s different about it?

• First the “Why”….▫ Background▫ Need for traffic control▫ Significant Problem

• Second…the “What”▫ “Still” a roundabout – with all applicable traffic rules▫ Size: 50’ – 80’ diameter▫ Fully mountable central & splitter islands Generally no higher than 4-5” – but clearly visible

• http://safety.fhwa.dot.gov/intersection/roundabouts/fhwasa10007/

Case Study:Tollgate Road @ MacPhail Road• Design

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Case Study:Tollgate Road @ MacPhail Road• Design▫ Fit into the existing paving.

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Case Study:Tollgate Road @ MacPhail Road• Design▫ Fit into the existing paving▫ Much smaller than “normal” roundabout

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Case Study:Tollgate Road @ MacPhail Road• Design▫ Fit into the existing paving▫ Much smaller than “normal” roundabout ▫ Deflection, Stamped & Mountable Concrete,

Defined Pedestrian Paths

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Case Study:Tollgate Road @ MacPhail Road• Design▫ Fit into the existing paving▫ Much smaller than “normal” roundabout ▫ Deflection, Stamped & Mountable Concrete,

Defined Pedestrian Paths▫ Center Island Design (Conspicuous, Mountable)

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Case Study:Tollgate Road @ MacPhail Road• Design• Construction

Case Study:Tollgate Road @ MacPhail Road• Design• Construction▫ Closed entire intersection for 3 weeks to expedite

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Case Study:Tollgate Road @ MacPhail Road• Design• Construction• Completed Project

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Case Study:Tollgate Road @ MacPhail Road• Design• Construction• Completed Project▫ Volumes

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Case Study:Tollgate Road @ MacPhail Road• Design• Construction• Completed Project▫ Volumes▫ Evening Rush Hour & Nighttime Video

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Case Study:Tollgate Road @ MacPhail Road• Design• Construction• Completed Project▫ Volumes▫ Evening Rush Hour & Nighttime Video▫ “Special” Situations

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Case Study:Tollgate Road @ MacPhail Road• Design• Construction• Completed Project• Lessons Learned

Case Study:Tollgate Road @ MacPhail Road• Design• Construction• Completed Project• Lessons Learned▫ Vehicular Deflection

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Case Study:Tollgate Road @ MacPhail Road• Design• Construction• Completed Project• Lessons Learned▫ Vehicular Deflection▫ Traffic Control Signs

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Case Study:Tollgate Road @ MacPhail Road• Design• Construction• Completed Project• Lessons Learned▫ Vehicular Deflection▫ Traffic Control Signs▫ Turn Signals

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Just what is a mini-roundabout??

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Mini-Roundabout

Just what is a mini-roundabout??

We hope it’s the “future

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Just what is a mini-roundabout??

We hope it’s the “future”….with long term positive impacts similar to the “normal” roundabout:

Just what is a mini-roundabout??

We hope it’s the “future”….with long term positive impacts similar to the “normal” roundabout:

Modern Roundabouts: Circa 1990: Est. less than 1002010: Greater than 3,000

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Just what is a mini-roundabout??We hope it’s the “future”….with long term, positive impacts similar to the “normal” roundabout:

Modern Roundabouts: Circa 1990: Est. less than 1002010: Greater than 3,000

Mini-Roundabouts:Circa 2010: Est. less than 102030: ???

Thank You

Questions and Additional Information:

http://www.harfordcountymd.gov/dpw/engineering/TransEng/roundabouts.html

Harford County Government Roundabouts - Website

FHWA Mini-Roundabout Design Manual - Website

http://safety.fhwa.dot.gov/intersection/roundabouts/fhwasa10007/

Jeff Stratmeyer – Chief Engineer, Harford County, MD DPW

E-mail: jmstratmeyer@harfordcountymd.gov