Improving Safety and Operations at Parliament & Carlton

I propose extending/moving the existing signal operation at Parliament & Carlton to include east‑side Carlton. Personal, physical observations and City traffic/collision data show that the intersection is currently treated as a T‑intersection, but actually functions as an offset intersection due to the proximity of the east‑side Carlton leg.[1]

A previous submission for this intersection, under a similar title, focused on improving left‑turn operations and pedestrian safety at the west‑side Carlton approach.[1] While those concerns relate to signal timing and congestion, this proposal addresses a broader issue: the east‑side (offset) Carlton leg, which functions as part of the same intersection but remains unsignalized.

Intersection Geometry

Parliament & Carlton is an offset intersection: Carlton meets Parliament at two closely spaced points.

• West‑side Carlton meets Parliament at the main signalized intersection.
• East‑side Carlton meets Parliament a short distance north, forming an offset leg.

Although only the west‑side leg is signalized, users experience the two legs as a single intersection.

Operational and Safety Issues

1. Drivers from east‑side Carlton face multiple conflicts

Vehicles emerging from east‑side Carlton (going westbound) must simultaneously:

• yield to pedestrians in the north crosswalk,
• find gaps in northbound Parliament traffic,
• find gaps in southbound Parliament traffic, and
• anticipate turning movements from west‑side Carlton.

This creates complex, unprotected decision‑making in a constrained space.

2. Eastbound traffic contributes to delay

Eastbound vehicles turning north are blocked by pedestrians in both the northern crosswalk on Parliment (going east-west) and northern crosswalk on east-side Carlton (north-south).

In a typical off-set intersection where it's entirely signalized, the east-west pedestrian traffic would not be an issue.

3. High collision risk relative to volume

Turning Movement Counts (TMC) and collision data show that this intersection ranks 4th highest in collision risk within the study area, despite not having the highest traffic volume. The elevated risk is driven by geometry and control design. You can review my analysis in the attached Excel document. [2]

4. Pedestrian and cyclist conflicts at both Carlton legs

The current configuration also creates risk for pedestrians and cyclists at both Carlton legs.

At the east‑side Carlton crossing, people travelling north–south must cross an unprotected point. Although westbound drivers have a stop sign, pedestrians and cyclists receive no protected phase, and drivers gap‑seek across both directions of Parliament traffic while entering the intersection.

At the west‑side Carlton crossing, pedestrians and cyclists face a related risk: vehicles emerging from east‑side Carlton and continuing westbound must merge into the main intersection.

Proposed Solutions

A. Extend the Signalized Control Zone

To address the root cause of the above-mentioned issues, we can extend/move the signalized zone:

1. Relocate the northern signal heads further north This brings the east‑side Carlton leg fully into the signalized area.
2. Shift the current north crosswalk on Parliament (going east-west) to north of the east‑side Carlton leg.
3. Operate the entire area as one offset intersection This removes gap‑seeking behavior and provides predictable, protected phases for all users.

Drawbacks: This option requires design work, signal equipment relocation, and possible curb/sidewalk adjustments. It may involve higher cost and longer implementation time than regulatory restrictions.

B. Make a portion of east‑side Carlton one‑way (eastbound)

Converting a short segment to one‑way eastbound would eliminate westbound movements that currently require gap‑seeking across pedestrians and both directions of Parliament traffic.

C. Prohibit left turns from east‑side Carlton (westbound)

Prohibiting left turns would remove the highest‑conflict movement while still allowing simpler right‑turn movements.

Drawbacks (Options B & C):

• Residual conflicts remain because west‑side Carlton traffic still merges near the offset leg.
• A left‑turn prohibition may face compliance issues as drivers may want to avoid rerouting.

References

[1]City of Toronto Centre Projects page referencing Parliament & Carlton as a “T‑intersection” (https://torontocentreprojects.ca/en/ideas/improvements-to-parliament-and-carlton-intersection).

[2] Cabbagetown Collision Data (Excel workbook provided by the author; attached).