Questions about Roundabouts:
1. Why is Wooster building roundabouts?
2. What are Wooster’s Plans for future roundabouts?
3. What are the plans for the Burbank-Oldman-Winkler Intersection?
A proper answer requires some:
• Definitions
• History
• Objective Data
• Myth-busting
• Real Life experiences
• Detailed Engineering Analysis
Not too long ago, when the concept of a “roundabout” was mentioned, you may have pictured a “traffic circle”, which are very different from modern roundabouts.
Other components:
• Central Island landscaping/features -Purpose
• Shield headlights
• Limit distractions, Maintains focus on the road
• Lowers Speed
• Raised Central Apron
• Encourages cars to stay in lane
• Allows for Large trucks to navigate
• Splitter Islands
• Lowers Speed
• Directs traffic entering & exiting
• Eliminates left turn movements
ODOT design standards for intersections (OMUTCD, L&D Manual Vol. 1, Section 400) provides guidance and “warrants” for various intersection improvements. These include:
• Vehicular volume
• Pedestrian volume
• School Crossings
• Signal systems
• Crash History
• Roadway Networks
• Rail-crossingproximity
Based on those items, ODOT considers3 types treatment options for intersections:
• Stop Control
• Traffic Signal
• Roundabout
The requirement for a traffic signal is based on a warrant analysis that involves consideration of one or more of the above-referenced warrant criteria.If a traffic signal is warranted, an alternative to a signal is a roundabout.403.1 states that "Generally, roundabouts can process high left turn volumes more efficiently than all-way stop control or traffic signals; as well as accommodate a wide range of side road volumes."A more objective way to compare the performance of a roundabout to that of a traffic signal (from a traffic flow standpoint is LOS)
The reduction in conflict points directly affects the number of crashes. Thegeometry and speed reduction directly affects the severity of crashes.
Roundabouts are one of the evidence-based safety countermeasures recommended by the FHWA.
Insurance Institute for Highway Safety (IIHS) Studies (2002 thru 2006)
• When Roundabouts replace 4-way stop controlled intersections:
• Vehicle delays reduced 13% to 23%
• Stopped vehicles reduced 14% to 37%
• When Roundabouts replace traffic signals:
• Vehicle delays reduced 89%
• Vehicle stops reduced 56%
• Overall Intersection Improvements when roundabouts installed
• Vehicle delays reduced 65%
• Vehicle stops reduced 52%
• One study found that installing roundabouts in place of traffic signals or stop signs reduced emissions (carbon monoxide, carbon dioxide, nitrous oxide) by 15% to 45%
• Based on those studies, the IIHS estimated that if 10% of signalized intersections in the US were converted to roundabouts:
• Vehicle delays would be reduced by more than 981 million hours
• Fuel consumption would be reduced by more than 654 million gallons (2018)
• Roundabout cost includes complete utility replacement (water, sewer, storm)
• Signalized intersection cost = $400K with signal equipment only
$750K with equipment and turn lanes
$1.0M with equipment, turn lanes, utilities
• While roundabouts are relatively expensive to construct, they do cost less than the average cost of a single fatal car crash (taking into account lost earnings, lost household production, property damage, medical costs, and other factors).
• AAA estimates that a single fatal motor vehicle crash costs the nation $6 million. ODOT considers roundabouts to be very cost-effective if they reduce fatalities and injuries.
The Unfamiliarity/Skepticismstatistics have changed over the years as roundabouts have become more common. We have seen this shift locally as well. The City Administration has received a good bit of feedback, which has been overwhelminglypositive.We have receivedsome negative comments from a handful of residents, mostly regarding pedestrian safety andadjacent property impacts.comments we have received include the following:
• "I think it's a good location for any improvement...like many people, I have seen what seem like many near misses."
• "I think this location is an obvious choice for traffic flow improvements/peanut roundabout"
• "I like roundabouts“
• "This is a great location for a roundabout“
• "I can't wait for this project to be done"
Source: Roundabout Database, https://roundabouts.kittelson.com/ https://www.kittelson.com/ideas/how-many-roundabouts-are-in-the-united-states/
• Most of US roundabouts built in last 20 years
• Data excludes other circular intersections
• Florida has almost 1600
• California has 840
• Texas has 808
• Pennsylvania has 216 (mean)
• South Dakota has 17
Even though the US and Ohio have been catchingup on the application and installation of modern roundabouts, some people still have some confusion about how to navigate a modern roundabout.
• This list is an attempt to simplify and summarize roundabout driving
• We also have a short video we can share on this same subject.
Large vehicles can’t navigate a roundabout…
• Modern roundabouts are designed for farm equipment, emergency vehicles, buses, and semi’s
• Radius & raised truck apron islands incorporated
• Also witnessed a semi back around a roundabout during final landscaping.
• Schools have indicated no issues with buses navigating the multiple, existing roundabouts in the City Roundabouts hurt business…
• Slower speeds improve ease of parking, walking, biking
• Increased ability to locate & approach businesses
• Golden, CO saw retail sale increase 60% along a road where a series of roundabouts were installed
• Meijer was initially concerned about this, but eventually saw the benefits Roundabouts aren’t safe for pedestrians & bicyclists…
• Splitter islands allow pedestrians to watch only one direction of traffic
• Slower vehicle speeds makes crossing easier
• More time for both pedestrians and drivers to react
• Bikes can cross with pedestrians, or ride in slow moving vehicle lane
• Gabe Tudor, Wooster City Schools Supt, indicated that they have had no issues with the existing roundabouts, have witnessed improved traffic flow and safety for both vehicles and pedestrians and stated that "our observations, coupled with our experience with the new roundabouts on Oak Hill and feedback from the police department and City officials, suggest that the proposedroundaboutcould alleviate traffic congestion and enhance pedestrian safety."
Roundabouts aren’t good for older adults…
• By 2025, 25% of all drivers will be over 65
• 40% of all car crashes involving drivers over 65 occur at intersections
• Older adults have increased difficulty judging left turn gaps-roundabouts eliminate those decisions
• Roundabouts eliminate head-on and right-angle collisions
• Collisions limited in number & severity
• AARPRoundabout Handouts available
Sources: FHWA, AARP
Specific Criteria for Intersection Improvements:
• Warrants for a Stop-Controlled Intersection:
• Traffic Volume
• Peak Hour Traffic
• Crash Rate
• Type of Crash –SerousInjury/Death
• Pedestrian Volume
• School Crossing/Proximity
• LOS
• ODOT,FHWA, and OUMTCD Criteria and modeling
• Funding Criteria
If Stop-Control is Warranted, Can a Roundabout be Constructed?
• Requires more ROW/Land Purchase
• Initial Costs are more/funding availability
• It WILLbe safer
• It WILL increase LOS
Contact the Wayne County Engineer for more information on these projects.
ODOT has been operating with a “roundabout first” evaluation process
• Have been willing to fund roundabout projects at a significant level with safety funds
May have heard the term “Peanut” Roundabout, or “Oblongabout”
• This is simply a combination of roundabouts or one oblong roundabout connecting multiple, offset intersections
• It still functionsas a single roundabout
City of HilliardExample:
• Several (four) roundabouts installed in a mixed use, hightraffic area.
• Adjacent to a high school, middle school and an elementary scho ol.
• Serves a soccer park, ball fields and a community center located in the same area as well.
• Safely and Efficientlyserves a high volume of pedestrian and vehicular traffic on the roadways. (Most are multi-lanedue tohigh traffic volumes)
City of Kent & Kent StateExample:
• Multiple roundabouts (2 large, 1 small) installed in a mixed use, hightraffic area.
• Adjacent to a college campus and athletic facilities
• Serves commercial, residential,and student housing located in the same area as well.
• Safely and Efficientlyserves a high volume of pedestrian and vehicular traffic on the roadways.
City of Dublin
• Large roundabout installed adjacent to a high school and residential area.
• Safely and Efficientlyserves a high volume of pedestrian and vehicular traffic on the roadways.
City of Delaware
• Peanut roundabout installed adjacent to a high school and residential area.
• Safely and efficiently serves a high volume of pedestrian and vehicular traffic on the roadways.
City of Kent & Kent StateExample:
• Roundabouts installed at the largest pedestrian volume areas
• Number of pedestrian/vehicle accidents was SIGNIFICANTLY lea than at signalized intersections
• Rate of pedestrian accidents at Roundabouts = 0.015% accidents/pedestrian (1/6448)
• Rate at signalized intersections = 0.6% (5/784)
• Accident Rate in this example = 40 times greater at signalized intersections than roundabouts
Recently completed roundabout in Lorain County, in North East Ohio.
Highlighted in a December Fox 8 news article.
City officialscalled it a “much anticipated peanut-shaped roundabout project” has been underway since September. The new roundabout will be located at theintersection of Stoney Ridge Road, Mills Road and Avalon Drive.
In the article, According to the Ohio Department of Transportation representatives stated that:
• Roundabouts are safer than traffic signals and can move traffic more efficiently with fewer delays.
• ODOT recognizes that roundabouts aren’t typically perceived as a popular solution among the public but said,
• “Much of that is due to a lack of education about their benefits and them being a relatively new traffic pattern for many areas of Ohio. Public reaction usually flips to positive within a year or two of them being installed and open to traffic.”
Wooster Fire Chief Saley reached out to the N. Ridgeville Fire Chief there to inquire about the experience of the fire service with this roundabout. The N. Ridgeville chief provided the following response: "So far, we have no problems with it and the community loves it. As a matter of fact, it cured a problem intersection for us that had a lot of accidents and near misses. The only negative that we have experienced so far was the time the road was closed during construction. It was actually completed fast, but it is a normally busy area. The roundabout was designed to accommodate large trucks such as our ladder truck. You actually can run over the curbs in the center of it with large trucks. It’s designed that way. I highly recommend it!"
Proposed location for a “Peanut” Roundabout
• Simply an elongated, single roundabout
• Currently being designed
• Only way to improve traffic flow due to the proximity of the two side roads
Traffic analysis and alternative evaluation indicated:
• This intersection was identified as a problem over 20 years ago, by former City Engineer Rick Oswald. Traffic analyses and evaluations were initiated at that time
• There is was no signal timing arrangement then or now that would adequately address the existing traffic volumeand traffic delays.
• Turn lanes can not be constructed between Winkler and Oldman to address the turn volume
• Even re-aligning Winkler or Oldman to create one intersection will not adequately improve intersection operation
• Traffic will only continue to increase as additional commercial and residential development occurs
• Accidents were not the deciding factor for the proposed improvements.
• Accidents are only 1 or 7 “warrants” for intersection improvements
• 8 accidents in past 3 years; most were rear-end, failure to yield for stopped vehicles
• Multiple “near misses”
• Continued, increased congestion will only lead to more accidents, and safety vehicle delays
The ODOT District3 Deputy Director, Bob Weaver, is an engineer and former Wooster resident who is very familiar with the traffic at the Burbank-Winkler-Oldman intersection. When the proposed roundabout was presented to him, he indicated, "This intersection is a great fit for the plan Wooster has in place and I am an advocate for the same."
Large Vehicle Design Considerations:
• Paved truck aprons around central island
• Paved aprons at entrance/exit lanes
Pedestrian & Bicycle Design Considerations:
• Will be the same asthe Oak Hill-Oldman roundabout
• Accessible pedestrian/bike crossings at each leg
• Safety zones in each splitter island
Driveway Design Considerations
• Shortenedand/or divided splitter islands
• Allows for all turning movements in/out of driveways
Alternative Analysis:
• Add Turn Lanes onBurbank at Winkler and Oldman –Maintain Signalization at each intersection
• Adding turn lanes forSouthbound Burbank, north of Oldman
• Would significantly increase impact and disturbance to properties
• Would increase the number of properties impacted
• These turn lanes would not solve the most severe vehicle delay and queue length deficiencies for current traffic volumes
• Added turn lanes increase number of lanes required to be crossed for left turns into driveways
• Adding turn lanes forNorthbound Burbank, south of Winkler
• Would significantly increase impact and disturbance to properties
• Would increase the number of properties impacted
• These turn lanes would not solve the most severe vehicle delay and queue length deficiencies for current traffic volumes
• Most severe deficiencies occur between Winkler and Oldman
• There is not enough room between these intersections to solve the queue length shortages.
• Requirements far exceed available space
• Severe overloading causes back-ups on Winkler and Oldman
• Adding these turn lanes would require an increase in signal phases needed for additional movements, and protected movements
• This option would still result in significant cost, increased impacts to adjacent residential properties, but result in little to no improvement in traffic LOS or back-ups
Alternative Analysis:
• Re-Alignment of Winkler and/or Oldman to create One, Signalized Intersection
• Winkler re-alignment: Would require the removal of at least 2 homes
• Oldman re-alignment:
• Wouldrequire removal of substantial parking places (85 lost) and communications building at soccer complex
• Would require significant additional parking to be constructed
• Even if aligned, a single, signalized intersection would not function adequately
• Similar cost to a roundabout, but with minimal changes in LOS or safety
• Would have to add single roundabout to make a viable option
Proposed Initial locationfor a “Peanut” Roundabout
• Bestgeometry
• Limited parking disturbance: 31 parking spaces lost
• Equal encroachment on NW and SE corners
• Significant encroachment on east-side parcels
Intersection Traffic Analysis
Detailsand Assumptions:
• High traffic volumes exceed intersection capacity for turning movements, vehicle delays, and queue lengths
• Traffic volumes have increased almost 30% in the last 5 years
• Average Annual Daily Traffic (AADT) in 2023 = 8,420
• AADT in 2018 = 6,510
• Average AADT from 2018 thru 2020 = 6,379
Intersection Traffic Analysis
Multiple movements that exceed storage length
• Red cells above
Multiple movements with LOS od D
Any changes in signal timing would cause additional delays in o ther movements, and increasethe overall intersection delay.
There is not enough area between Winkler and Oldman to add turn lanes
• 145 feet between intersections
• Required length more than double that available, and queues overlap
Intersection Traffic Analysis
Multiple movements that exceed storage length
• Red cells above
With additional construction, a NBLT lane could be constructed, which MAY improve LOS for that one movement.
Would be similar in cost to roundabout Would still have functional inadequacies
Intersection Traffic Analysis
No movements exceed storage length
All movements have LOS of A or B
Proposed location #2 for a “Peanut” Roundabout
• Adequategeometry
• Increased Parking disturbance: 49 parking spaces lost
• Limited encroachment on SE corner
• Increased encroachment on NW corner
• Limited encroachment on east-side parcels
The Engineering division attempted to share information and offered to meet with adjacent property owners multiple times during the initial planning & design of the project. Only the County Commissioners and one resident agreed to meet, and both of those entities were in favor of the roundabout.
Proposed location #3 for a “Peanut” Roundabout
• Adequategeometry
• Increased Parking disturbance: 49 parking spaces lost
• Limited encroachment on SE corner
• Limited encroachment on NW corner
• Limited encroachment on east-side parcels
• Approach islands adjusted to accommodate adjacent driveways
This option limits the impacts on all adjacent residential property owners as much as possible
Proposed location #3 for a “Peanut” Roundabout
• Adequate Geometry for:
• School Buses
• Large Fire Truck
Gabe Tudor, Wooster City Schools Supt, indicated that they have had no issues with the existing roundabouts, no bus navigation issues, no student rider issues, and have witnessed improved traffic flow and safety for both vehicles and pedestrians and stated that "our observations, coupled with our experience with the new roundabouts on Oak Hill and feedback from the police department and City officials, suggest that the proposedroundaboutcould alleviate traffic congestion and enhance pedestrian safety."
Proposed “Peanut” Roundabout
• Concurrentlywith the above steps, the City is also soliciting potential funding sources for construction
• This intersection was included in the 2023 TIF area, anticipating the need for improvements
Draft -Proposed Roundabout Schedule, IF no delays
This schedule is tentative:
• Some aspects could be completed sooner, allowing for construction to start sooner.
• Consideration has been given to scheduling as much construction while school is out, where possible.
• Significant unknowns until design is more complete would be utility relocations and ROW acquisition.
Please note:
• Handoutsavailable from ODOT, FHWA, andAARP