Home > Intersection Safety > Roundabouts

Overview of the Northeast U.S. Roundabouts Peer Exchange

Jeffrey Shaw
FHWA Office of Safety

Downloadable Version
PDF [1.7 MB]
PPTX [6.39 MB]

slide 2

Purpose of the Event

Magnitude of the Intersection Crash Problem
Compared to NY, roundabout implementation has been slow in surrounding States
Important U.S.–based information to share
Recognized benefits of in-person events

slide 3

A Partnership Foundation

Jointly–funded effort between HQ, RC and Division Offices
Partnered with ConnDOT and ITE Roundabouts Task Force
Assembled an Event Planning Committee representing key audience backgrounds:
- Hillary Isebrands (FHWA RC)
- Charles Harlow (ConnDOT)
- Bob Ramirez (FHWA CT)
- Francisco Lovera (RIDOT)
- Caroline Trueman (FHWA NJ)
- Mike Mastaglio (RK&K)
- Ed Stollof (ITE)
- Joe Balskus (Tighe& Bond)
- Andy O’Brien (O’Brien Traffic)
- Jeff Todd (Traffic Planning & Design, Inc.)

Slide 4

1½ Days of Roundabouts!

How far have roundabouts come in New England and the Upper Mid–Atlantic?
What important lessons have been learned that practitioners should know about?
What challenges lie ahead?
How can we accelerate the implementation of roundabouts in our States?

Slide 5

The...GOOOOOOOOAL!

EDUCATE

NETWORK

Slide 6

Status of Roundabouts in NEUS

The 9 Peer Exchange States estimated:
- 98 existing roundabouts in operation
- 74 in–progress planning/design
- Over 100 add’l roundabouts at non-State intersections

Slide 7

Notable Lessons Learned

Importance of Education, Marketing & Outreach
Retrofits of existing circles/rotaries can help overcome regional legacy of circular intersections
Applying roundabouts at challenging/unusual intersections can yield great success
Roundabouts are scalable, adaptable and can be context sensitive and sustainable solutions

Slide 8

Marketing/Education/Outreach

Updated FHWA Roundabouts Video & Brochure
Importance of working with Education and EMS communities

Tractor trailer training [Photo credit to Brian Walsh (WSDOT)]

Slide 9

Example of Circle/Rotary Retrofit

Example of Circle/Rotary Retrofit [Graphic content credit to Andy Paul (MassDOT HQ) & Joe Frawley (MassDOT D3)]

Slide 10

Applied to Challenging Locations

Applied to Challenging Locations Example [Graphic content credit to Will Britnell (ConnDOT)]

Slide 11

Capable of High Throughput

Photo content credit to Mike Dugas (NHDOT)

Slide 12

The Solution is Out There

Graphic content credit to Scott Richie (RTE)

Slide 13

Context Sensitive Opportunities

Photo content credit to Scott Richie (RTE)

Slide 14

Adaptability for Local Intersections

Graphic and photo content credit to Rich Balgowan Hamilton Twp NJ PW

Slide 15

Roundabouts in the Near-Term

MassDOT creating roundabout-specific tools/products
Accessibility of multilane crossings at roundabouts
Capacity analysis

Slide 16

Upcoming MassDOT Tools/Products

Roundabout Planning/Screening Tool
- Working with the Central Transportation Planning Staff (CTPS) from the Boston MPO on the development of a tool to assist designers in when to consider a roundabout versus a signalized intersection
Local Community Reference Guide
- To provide details on the benefits of roundabouts and relationship to traffic calming and livable street aspects to ensure that a roundabout is considered for the correct reasons

Slide 17

Accessibility Aspects of Roundabouts

Proposed PROWAG rulemaking targeted for fall 2010 by USDOT
Issue at multilane roundabouts is one of ACCESSIBILITY not safety

Photo content credit to Scott Windley (USAB)

Slide 18

Capacity Analysis Techniques

Growing Number of Software/Model Choices
- Gap Theory (SIDRA, SYNCHRO, VISSIM, Paramics)
- Empirical (RODEL, ARCADY, NCHRP 572/HCM2010)
Different model inputs/assumptions can yield different results
Important to Spend Time Wisely
- Rules of Thumb/Lessons Learned
- Hourly-based flow check can Save Time

Slide 19

Early Returns/Preliminary Results

Quality feedback from over 85 attendees: 4.6/5
Average Knowledge Gained (self-assessed):
- from 2.65 (Before) to 3.52 (After)
Some Resulting Action Items:
- Seek out lower-cost implementation opportunities
- Immediately distribute copies of the new FHWA DVD
- Get a mini roundabout piloted this year
- Discuss a multi-State follow-up meeting
- Evaluate future regional Roundabout Peer Exchanges