Hurontario LRT engineers innovative ‘Hwy. 403 flyover’

A busy interchange along the future Hurontario LRT route had the potential to create major congestion. Here’s how engineers resolved the complicated obstacle, ensuring traffic flow for both the LRT and your family’s SUV.

Actually, we can get you here from there.

Rathburn Road West is home to one of Mississauga’s largest transit hubs. On any given day, 1,800 MiWay buses pass through the City Centre Transit Terminal. Meanwhile more than 630 GO buses deliver travellers to one of the region’s busiest stations just down the street. It only makes sense the Hurontario Light Rail Transit (LRT) line connects with the same stop.

Beyond transit, this bustling area also plays host to one of the largest shopping malls in the country, as well as Sheridan College’s Hazel McCallion campus.

The team working on the Hurontario LRT project faced a significant challenge – how to get commuters from Hurontario Street onto Rathburn Road W, in order to connect all these pieces and people.

A map shows the expected route of the flyover.

The innovative ‘403 flyover’ will be a separate structure crossing Highway 403, in parallel to and separate from the existing vehicular bridge.

The original alignment would have seen the LRT cross alongside vehicular traffic on the existing Highway 403 Bridge, obstructing both on and off-ramps and significantly impacting vehicular traffic flow. This challenging situation would turn into a congestion nightmare for both commuters and drivers. But engineers found a solution.

The problem will be solved using an LRT-only bridge the team refers to as the ‘403 flyover’. The bridge will connect transit riders from Hurontario Street to the City Centre Transit Terminal and GO bus terminal on Rathburn Road West.

A map showing the placement of the LRT line, near Square One.

A bird’s eye view of the City Centre LRT stop on Rathburn Road West, illustrating the multiple transit connections and link to Square One.

The concept for the bridge was the result of traffic and LRT operation studies conducted by Metrolinx in collaboration with the City of Mississauga and the Ontario Ministry of Transportation. The study concluded that separating the LRT from the regular vehicular and bus traffic on the interchange would not only minimize traffic impacts in the area, but also allow for a smoother and faster LRT service.

Looking over different alternatives, engineers reasoned, a separate structure crossing Highway 403, in parallel to and separate from the existing vehicular bridge, would offer the best solution not only for the long term LRT service but also by minimizing the impact of the existing bridge during construction.

How will the flyover operate?

The LRT guideway will seamlessly shift to the west side of Hurontario Street immediately north of the existing bridge, cross over Highway 403 and branch off to Hurontario to the east, or to Rathburn to the west in a Y shape.

How will the LRT turn around to leave the stop?

It won’t. LRT’s are bi-directional. The driver will walk through the vehicle to the other end and continue the return journey.

So you will be able to get here from there. But it takes a lot of planning for engineers and designers, to make sure that future trip is seamless.

(Story by Noelle Wannamaker, Metrolinx community relations and issues specialist.)