Traffic Calming Options Considered for 6-Way Intersection

The entrance to the Village of Mariemont to the north is a six-way intersection where Plainville, Murray and Madisonville Road converge. At a presentation in early February, Jonathan Wiley, a transportation engineer with KZF Design, presented several options that aim to improve the flow of traffic at that intersection. In the fall, KZF engineers studied traffic patterns through the intersection and then modeled six different revisions. The two options that were the most feasible came down to a roundabout or traffic lights. Mr. Wiley stated that the current intersection does not meet today’s standards for keeping traffic moving. He acknowledged that there have been very few accidents at the intersection, and attributes it to the fact that drivers go very slowly because it is confusing and difficult to determine who should proceed next. Given all the factors, KZF determined that a roundabout is the best option for keeping traffic moving, with speeds of 18-20 miles per hour through the intersection.

Attending the presentation were representatives from businesses, the Mariemont School Board, Columbia Township, Mariemont Council, and other interested parties. Mike Lemon, Administrator of Columbia Township, spoke in favor of the roundabout as a way to improve the traffic flow and the look of the area. He reminded the group that roundabouts are common in England, and Mariemont is modeled after an English garden city.  Most of the affected land lies in Columbia

Township, but there is a 10-foot easement in the Village

of Mariemont that is affected by the roundabout and a proposed bike path, and so they are seeking cooperation from the Village.

Future traffic through the area was considered, to take into account increased traffic from Emery Park and Nolen Park condominiums, as well as a proposed apartment complex. Traffic engineers estimate an eventual 15% increase in traffic and their models show that both the traffic signal plan and the roundabout plan can handle future growth. KZF estimates construction of a roundabout would take 2-3 months, with traffic maintained. Installing traffic signals would be a much easier process. Installing traffic lights was not considered the best option, however, because speed through the intersection would be fairly high (30 mph) on Plainville when the lights are green. The engineers see the roundabout plan, with “splitter islands” as also being safer for pedestrians, since they would be able to cross one lane, pause at the island and then cross another lane, reducing their exposure.

KZF has presented their findings to the five member Planning Commission that will vote sometime in March and then present the final determination to Council.

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Comments

  1. I think this a great solution to a very confusing and dangerous intersection. It will make pedestrian, bicycle and vehicle traffic much safer.

  2. I am a citizen of Mariemont. I have no objection to roundabouts, to a traffic signal, or to leaving the intersection exactly as it is. I do object to Village/resident funding of any of these options, as I simply do not consider it to be enough of a Village priority to merit any additional expenditure.

    A clear explanation of anticipated costs to Village residents for either a roundabout or traffic signal would be appreciated.

    Thank you.

  3. I would be in favor of a roundabout as opposed to traffic lights. The cons with traffic lights would be the backing up of traffic north and south bound on Plainville Road as the majority of traffic would be flowing in these two directions. With much less traffic entering the intersection from Murray I think would cause a light to be on red for the majority of traffic along Plainville and Madisonville Roads unnecessarily.

    The roundabout option makes the intersection more pedestrian friendly. With an island midway at a crossing makes it easier as a pedestrian to cross one part before proceeding to the over side. As a pedestrian at the current intersection I am very wary of the traffic flow often not knowing which streets cars are turning onto. Also I am aware that many drivers are looking at the other cars at the intersection to determine whose turn is next, and therefore not looking out for pedestrians.

    I have one comment for Columbia Township. Have they considered making their side of Murray Avenue one-way in the opposite direction to the Mariemont Side? This takes one more street entering the intersection out of the equation.

  4. I think the design is fantastic and efficient.
    Roundabouts are standard throughout Europe and are slowly being adopted in the US. Why go to the expense and maintenance of a stoplight system when a roundabout naturally funnels the traffic and because of the roundabout design, results in a natural throughput speed.

  5. I think it’s important to include the proposed bike path in the immediate planning for the roundabout rather than the ‘future’ planning. I bike through there and connect to the Fairfax trail… I don’t see where cyclists have a safe pathway in the plan without the new bike path. The designers acknowledge that the intersection is not really a safety hazard now. I believe we will create one for cyclists as cars will be able to whip around the roundabout with no stop, and drivers not familiar with the area will be confused by a roundabout. I believe we would be creating a problem that did not previously exist unless we take care of the bike path from the get go.

  6. I am also interested in the cost to Mariemont residents, but am very much in favor of a roundabout. I lived in Dublin, Ohio as roundabouts were being installed, and they made a huge difference in calming and organizing traffic flow at many intersections as well as provided a beautification aspect to the community.

    I do suggest, however, some sort of “public education” on the use of roundabouts be added to the agenda. Most people around this area are not familiar with them, and they can be a bit intimidating at first. In Dublin, there was one tragic accident at the very beginning of the roundabouts being introduced in 2003, but as far as I know there have not been any since.

  7. I may well be in the minority here, but I come from Portland OR where roundabouts are a fact of life, especially in the outter streets of the city. In my experience they are a bad idea. They are difficult to get into, and for many people, confusing as well. Moreover the building of some 100 apartment units on the site sounds like a perscription for even heaverier traffic. Aurely a better solution can be found!

  8. I second Janet’s suggestion that Columbia Township (and the City) consider making the other side of Murray one way (west to east) to complement Mariemont’s current east to west direction. The illustration incorrectly reflects Mariemont’s Murray going west to east. I also support Matt’s counsel that serious attention be paid to making the bike path integral to the plan – it doesn’t have to be built now, but planning now is vital.

  9. This is a very forward looking and practical plan for the intersection. We have each had ‘close call’ which of course are not filed with our police department. Traffic flow will be improved and drivers will feel free of the uncertain ‘stop’ and ‘go’ that we have now. Other progressive cities have wisely incorporated round-abouts. We will all need to learn how to use them. Some of us wl be familiar with them from other area communities and of course those who travel in England will be mos comfortable. Thank you. Jane an Jo

  10. I agree with Dick Demaret above… I drive through that intersection daily on my to and from work. Never have a problem. This is the last place I would put a roundabout…

  11. I find it interesting that people imagine vehicles will “whip around” a roundabout, picking up speed like a slingshot. What actually happens is the car slows to a nearly full stop before making a 90 degree right turn. Approaching the roundabout is like approaching a T-intersection, not a merry-go-round! I was reminded of this recently driving around Victorian Village in Columbus, OH – there is definite traffic calming as drivers slow down to get around the mound in the middle. Traffic lights waste energy & require maintenance. As well, I imagine drivers will speed up along Plainville Rd. – alongside the Elementary School and Parish Center – to try and catch a green light. If you want to try a roundabout very close by, drive down Madison Road and take the left turn towards MedPace just before Red Bank Road. I think a roundabout would make a beautiful entrance to the village.

  12. I go to Indianapolis frequently and there are lots of Roundabouts up there – especially in Carmel, IN. I’ve also driven in Italy and have found them to be very safe, easy to navigate and they keep traffic moving. I would definately support one at this intersection. In fact, they should also consider putting one in by the Frisch’s Mainliner at the western edge of Fairfax. That seems to be the place that most traffic backs up and it could easily be fixed by adding a Roundabout.