Hwy. 400 Bridge work ramps up on Finch West LRT project – Detours ahead

Major bridge work is always a very big deal. It also means patience from those travelling nearby. A project involving the Highway 400 crossing at Toronto’s Finch Avenue, will cause some detours. But the disruption won’t be too large, thanks to an engineering process that will dramatically speed up the replacement. Here, we span the details.

(Update – New images added on June 11, 2020.)

It takes a lot of skill to replace a bridge.

But in this case, not as much time as you might expect.

As work progresses for the Finch West light rail transit (LRT) project, ramps and roadways will be temporarily closed to accommodate the replacement of the Highway 400 Bridge at Finch Avenue. It’s an important step in the construction of the new transit line.

That work will take place June 12-15 and June 19-22.

Image shows metal supports in a large area of concrete.

Here’s an image from the deck construction, that gives you an idea of the size of the expanse. (Metrolinx photo)

Finch West LRT line will pass below the existing Highway 400 Bridge at Finch Avenue West. Construction of the line has accelerated the Province of Ontario’s plan to rehabilitate the Highway 400 Bridge.

Using a ‘rapid bridge replacement’ (RBR) method, constructor Mosaic Transit Group has already done a significant amount of work to prepare for the job. In February, Mosaic received and placed the large reinforced concrete girders to build the framework for the bridge decks. The girders were then hoisted in place on scaffolding that has been set up beside Highway 400.

The real – and literal – heavy lifting will happen over two upcoming weekends in June, where these bridge decks will be moved into place on Highway 400 to form the new bridge spans. During the first weekend, Mosaic will work 24 hours to lift the existing southbound bridge and replace it with the pre-constructed bridge deck.

Image shows a construction aea, with crews working on the top part.

A bird’s eye view of the work. (Metrolinx photo)

The same will happen on the second weekend, where the northbound bridge will be replaced using the same approach.

The RBR method helps reduce the number of traffic disruptions to motorists from years to two weekend closures – June 12 to 15 and June 19 to 22.

Crews work under a bridge.

Crew repairing north facing abutment wall. (Mosaic Transit Group)

On the weekends of the planned closures, sections of the Highway 400 and Finch Avenue will close at 10 p.m. on Friday and re-open to motorists by 5 a.m. on Monday.

Read more about those impacts in our construction notice.

Image is a map of the road closures.

In case you missed it, you can catch the video of the prep work involved here.

So while you’ll need a bit of patience while the bridge work takes place, you’ll be able to point out to others why it’s not as onerous as it could have been.

Want to see other transit related progress Metrolinx is spearheading? Then check out this special page.