Well, I asked the City if it wouldn’t be a good idea to ask the Province to include room for an extra (third) east-bound OR174 lane under the new Cyrville Bridge.
[Just to refresh your memory; the Province is replacing the Cyrville Bridge over the 417/OR174. This will shut down Cyrville Road for two years. There will be additional room for a new east-bound 417 lane, but the west-bound lanes will be restricted to the current two lanes of 417 and two lanes of OR174. A new span will be added north of the bridge to house an extended St. Laurent off ramp so that it is available only to OR174 vehicles. This ramp will connect with the current 417E ramp which is also where the new third lane of the OR174 is to end. This will prevent cars from the 417 exiting at St. Laurent.]
The answer from Nancy Schepers was that the Province’s plans were based on a study that used the best City provided estimates of the early 2000s to a horizon year of 2021. She mentioned that the estimates have been updated, but that the updated numbers have not been used by the Province. She also said that there were no plans to widen the OR174 when the study was done.
Given that the OR174 has already been widened to three east-bound lanes from the 417 to Blair, and similar widening is happening this summer to the west-bound lanes, I asked whether the City feels that things have changed. I also asked for the latest traffic counts.
I got no answer about whether the City thinks conditions have changed enough to ask for a change in the bridge structure. (Aside: The City has augmented the Provincial plan and is paying $5M to have the bridge structure widened to four lanes.) It seems to me that since they are now widening the OR174 to three lanes per direction, there should at least be room for three OR174 lanes under the new bridge. That bridge will be in place for 60+ years. That is a long time to be funneling traffic from three lanes down to the same two lanes that were planned in the 1960s.
I did get some traffic counts:
As per your request, here are the 2005 morning peak hour volume at the requested locations:
- West-bound OR174 immediately east of Blair Road = 3650
- Entering OR174 from the Blair Road ramps = 600
- Leaving at the 417E ramp = 250
- Exit to St. Laurent Boulevard = 750
- West-bound 417 passing under Cyrville Bridge = 6850
These numbers were used in the modeling exercise for the TMP update.
I am assuming that the 6,850 vehicles attributed to the west-bound 417 passing under the Cyrville Bridge is actually the sum of vehicles on both the 417 AND the OR174 since pushing almost 7,000 cars through two lanes seems unreasonable to me. So, in pictorial form it looked like this in 2005:
It is no surprise that the TMP (2008 update) now identifies the need to widen the OR174 from the 417 to Jeanne d’Arc. The number of vehicles using the two OR174 lanes between Blair and the 417 is listed as 4,250!
So, if the need exists to widen the OR174 up to the 417, why does the City not think there will be a need to allow the third lane to pass under the Cyrville Bridge? The reasons given are that the extended St. Laurent ramp will take cars off the OR174 sooner; that there will no longer be weaving of cars from the west-bound 417 to the St. Laurent off ramp; and that both lanes of the OR174 will continue over St. Laurent, removing the need for cars in the right lane to merge left to avoid the St. Laurent exit.
Using the 2005 number as if they were current: The extended off ramp will remove approximately 750 more cars from the number passing under the Cyrville Bridge – this leaves 3,250 vehicles in the two OR174 lanes. There are also about 2,850 vehicles on the 417 lanes passing under the Cyrville Bridge. (This number may go down as cars which previously wove across the OR174 will be continuing north on the Aviation Parkway to Ogilvie Road to get to St. Laurent. The numbers provided can not provide this detail.) There is no merging between these lanes until west of the bridge so the OR174 could not take advantage of surplus capacity from the 417 lanes.
So, in 2005 numbers, it would seem that there is capacity to carry the OR174 traffic (3,250 vehicles per hour) onto the 417 with only two lanes. If I assume 2,000 cars per lane per hour, two lanes should carry about 4,000 cars in the peak hour. The OR174 will only be at 81% capacity once the St. Laurent off ramp is extended – again, using 2005 traffic counts.
So is a spare 19% enough to handle the growth of Orleans, Rockland, etc., traffic over the next 60+ years? Remember, there are two big roads people from the east can use to cross the Greenbelt, the OR174, and Innes Road. I understand that Innes is pretty much at capacity and the prospect for widening it further is not good. Thus, I think most of the new traffic will be coming along the OR174; where the three lanes will narrow to two lanes under the Cyrville Bridge.
Now think of the scenario where the Inter-provincial Bridge is built at Kettle Island. The traffic will be routed down the Aviation Parkway to the 417. The new N-W ramp from the Aviation Parkway to the 417 will replace the St. Laurent off ramp. (There will be room for only one ramp in the new span.) People will instead, leave the OR174 via a new E-N ramp onto the Parkway to Ogilvie Road to St. Laurent. This will not add any extra vehicles under the Cyrville Bridge, but will add merging traffic into the northern OR174 lane just west of Cyrville. If there were a third west-bound lane, the extra traffic could better be absorbed.
So, what do you think; should the new Cyrville Bridge be lengthened to allow for a future third OR174 west-bound lane?