Route 83 at Oakland/Summit and

Woodbridge Streets

Town of Manchester

Woodbridge Street

Woodbridge Street

Summit Street

No. Main Street

(Route 83) Oakland Street

(Route 83)

Old No. Main Street

Summit Street

Apell Place

Background – Woodbridge Street

at Summit Street

• 26 crashes over 3

years (4/2009-3/2012)

• 8 Injuries

• 14 Angle/Turning

• Very high for volume

• Confusion over who

has right of way

Woodbridge

Street at Summit

Street

• Signal considered, rejected due to railroad crossing,

congestion, complications with other intersection

• Town officials suggested roundabout with rail

crossing

• Addresses issues at this intersection

North Main at

Oakland/Summit

• DOT review indicated

backups from signal would

interfere with roundabout

• Second roundabout proposed

• Crash Pattern Addressed

• Delays Substantially Reduced

• DOT and Town Engineering Staff Concur on

Concept

What is a Roundabout?

• Similarities to old “traffic circles”, but with

significant differences

• Used in Europe for many years, have

become very popular in U.S. due to

reductions in accidents and congestion

• Over 1,000 in U.S., including Colorado,

Florida, Maryland, Vermont, many others

• Single lane vs. multi-lane

Missouri DOT Video

Roundabout vs. Traffic Circle

• Drivers yield on entry

• Much smaller circle (reduces speed,

congestion and accidents)

• No weaving, no lane changing

Two circulating lanes

NOT a Roundabout

One exit lane

NOT a Roundabout

Approx. 400 foot

Diameter

Approx. size of Typical

Roundabout

150’ Diameter

Approximate size

of Cape Cod Circle

West Haven (Before)

West Haven (Rendering)

West Haven (Built - 6/08)

Advantages of a roundabout

Compared to signals, roundabouts provide:

• Improved Safety

• Reduced Delays/Congestion/Pollution

• Less Pavement/Improved Aesthetics

• Approximately Same Construction Cost,

Lower Maintenance Costs

Insurance Institute for Highway Safety

Accident Reductions

Insurance Institute for Highway Safety Report

www.highwaysafety.org

Compared 24 Roundabouts (single and multi-lane)

in 8 states to signalized and all-way stop

controlled intersections they replaced:

• Total crashes reduced by 39%

• Injury crashes reduced by 76%

• Fatal/Incapacitating crashes reduced by 90%

• Pedestrian crashes reduced by 30-40%

Killingworth Roundabout

2013 National Safety Award

50% Reduction in Crashes, 86% Reduction in Injuries

• Lower speeds (15-25 MPH)

• No left turns

• Fewer decisions to make/information to

process

• Reduced number of conflict points

Reasons for Improved Safety

Reasons for Improved Safety

Crossing conflicts – highest chance for injury

Reduced Delays – Ellington 5 Corners

Reduced Delays – Ellington 5 Corners

• Went into roundabout operation on July 4th

weekend, 2011

• Confusion eliminated

• Delays virtually eliminated, even while in

construction

The new Round About at the 5-corners Is "the greatest

thing since sliced bread" as they would say. I've been

traveling through there daily since 1968 and traffic has

never flowed more smoothly as it does now.

It works so slick. I have never seen a back-up since the

day they put the barrels up during construction.

Ellington

Driving a Roundabout

• Entering traffic

yields to traffic in

roundabout

• All traffic goes

right

• Yield to

pedestrians

Crosswalks

Splitter

Islands

Landscaped

Central Island

Truck

Apron

Sidewalks

Roundabout Features

Truck using truck apron

Rear wheels on apron

Deflection limits

cars to 10 - 20 MPH

Roundabout with rail line

(Jensen Beach, FL)

Closely Spaced Roundabouts

Buffalo, NY

Other

Enhancements

• Decorative Lights

• Sidewalks

• Landscaping

• Gateway Treatments

West Haven

(Built – 9/08)

Landscaping

Sunoco

Cumberland

Farms

Dzen’s

Helps focus driver’s eye

on oncoming traffic by

obscuring traffic on other

side of roundabout

Traffic Simulation

• Based on PM Peak Hour volumes

• Buildings are not exact replicas

• Speed is approximately four times actual speed

Simulation video

Overall Plan

No. Main Street

(Route 83)

No. Main Street

No. School Street

Main Street

(Route 83)

Reduced from 4 lanes to 3

lanes, shoulders widened for

bicyclists, bus stops Lane use revised –

only one through lane

Excess pavement reduced,

crosswalks shortened by

up to 31 feet

Cost/Funding • Approximately $5 million (all 3

intersections), estimate will be refined

• Funding will be Federal and State, no town funds

• Any aesthetic enhancements may require town participation

• Town would be asked to maintain landscaping, if desired

Approximate Timeline

• Meet with Railroad company (2/19/15)

• Meet with BOD (today)

• Public Meeting, Conceptual Stage (April/May)

• Arrange funding, initiate project, begin design

• Public Meeting, 30% Design Stage (2016-2017)

• Acquire ROW, Permits, complete design

• Bid, Award, Begin Construction (2018-2019)

• Estimated 1 to 2 Construction Seasons

Questions?