The Great Eastern/Petite Forte Roundabout Pilot

Traffic staff from the City have recommended (as of this week) that a roundabout not be replaced at the intersection of Great Eastern Avenue and Petite Forte Drive. The roundabout worked, but it’s being recommended against because the majority of people who submitted feedback, have opposed it. Read on, for full analysis and my commentary.

In 2017, as many would know, the City completed a pilot project at the intersection to address the concern of high speeds travelling along Great Eastern, as well as the difficulty of exiting Petite Forte onto Great Eastern. This action was important for driver and pedestrian safety.

The solution proposed, and implemented as a pilot, was a mini-roundabout.


Data was collected in 2016 to determine if action was necessary, it was collected just before the roundabout was put in place, and when the roundabout was in place. Here is the data:

What does this data mean?

September 2016:
A. 85% of drivers went 60 km/hr or less.
B. 68.8% of drivers went 50 km/hr or more.
C. Average speed: 52 km/hr
D. Car count (24 hours): 5586

August 2017 (immediately before roundabout was put in place)
There was construction taking place on Kenmount Road, which potentially drove more traffic into your neighbourhood.
A. 85% of drivers went 54 km/hr or less.
B. 31.2% of drivers went 50 km/hr or more.
C. Average speed: 43 km/hr
D. Car count (24 hours): 6537

October 2017 (with roundabout in place)
A. 85% of drivers went 49 km/hr or less.
B. 15.3% of drivers went 50 km/hr or more.
C. Average speed: 41 km/hr
D. Car count (24 hours): 5803

It is clear through the data collected, that the roundabout worked at slowing traffic. And it’s clear that, previously - without traffic-calming measures - most drivers are speeding along this section of Great Eastern.

I was surprised and disappointed that the data shows that in September of 2016, 68.8% of vehicles travelling along the street, were going above the 50 km/hr speed limit. Nearly 70% of cars were speeding. That’s astounding. 

There are three data sets above. September 2016, August 2017 and October 2017. 

The most direct situations to compare, are September 2016 and October 2017. This numbers are very different in August 2017 prior to the roundabout because a significant volume of traffic was added, as people aiming to bypass construction on Kenmount Road used Great Eastern. Many more vehicles, many without area familiarity, travelled the street, so it slowed down vehicles. I.e. congestion and unfamiliarity slowed speeds. 

While the roundabout was in place, the percentage of people speeding dropped to 15.3%. Without the roundabout, it was 68.8% (2016), with the roundabout: 15.3%. That is a substantial drop. And therefore a substantial increase in safety. Even if you consider the 2017 results (when the traffic was added due to the construction as described above) it dropped from 31.3% speeding, to 15.3%. Essentially, from 3 in 10 speeding, to 1.5 in 10. That’s also still a substantial drop. 

Average speed also dropped from 52 km/hr to 41 km/hr -  an 11 km/hr drop.

Therefore, why have staff recommended it not be put back in place?
Because the public demanded it.

Here is their conclusion:
“This project was highly successful from a technical perspective and directly addressed the concerns raised about speed in the neighbourhood. Typically with traffic control changes that are not critical the City seeks a majority support from the local residents before moving forward with a change. There is clearly not the required level of support for this particular modification. As such it is not recommended to implement this change permanently. Great Eastern Avenue will be brought forward for other traffic calming treatments in its due course as part of the overall traffic calming policy ranking.”

The City completed a survey, specific to the roundabout. We received 976 responses. On a five point scale, five being the highest support:

kenmount terrace roundabout.PNG

483 individuals are very opposed to the roundabout, with many fewer for the overall, higher scores.

With no roundabout, that leaves us back at square one. At present, there is nothing in place to slow traffic at that intersection. Which, I hope, doesn’t mean with the snow melted, that we will return to the levels of speeding we saw before.

Residents have brought up other solutions, and these are staffs response to them:

3-way stop:
“A 3-way stop is an inappropriate traffic control mechanism to use at this intersection. The large flows along Great Eastern in comparison to Petite Forte would acclimatize drivers to a condition where there is rarely an opposing vehicle at the stop sign. This in turn leads to non compliance which is a very large safety concern for both drivers and pedestrians.”

Speed bumps:
“Speed bumps are not an appropriate tool for Great Eastern, speed cushions are the appropriate tool that fill this desire. In general we try to avoid speed cushions on roads that serve as bus and emergency routes and as main accesses into communities. Carrick Drive is an exception to this. In the future when Great Eastern is addressed under the traffic calming policy speed cushions will be an option on the table. Related to the request for speed bumps was the statement that this pilot project was not technically successful because it didn’t affect speeds further down Great Eastern Avenue. This pilot was never intended to affect speeds further away along Great Eastern. All traffic calming devices, including roundabouts and speed humps have a localized effect. This is why roundabout corridors are more successful than isolated roundabouts and why speed humps are installed in a long series of humps rather than at an individual point.”

Where to from here?
Great Eastern will be back up for consideration in traffic calming along with many other streets in the City. Unfortunately, due to the scoring system which determines the severity of a traffic problem, Great Eastern is well down the list. 

We need to work together on solutions. 

In the meantime, drive cautious, talk to your neighbours about the situation, and get in touch with me.

This is in Committee on April 11, here is the agenda.

Following Council's Committee of the Whole considering it on April 11, it will then go to Council for further voting on whether the staff recommendation is accepted.

Ian Froude