In an industry based on the design, creation and installation of hot mix asphalt, the easterly extension of Highway 407 would seem to be a good news story.
That story was one of the agenda items of the Ontario Hot Mix Producers Association's recent fall seminar.
Approximately 700,000 tonnes of hot mix asphalt was used in the first phase from Brock Road in Pickering, Ont. to Harmony Road in Oshawa, Ont. and an estimated 1.5 million tonnes is expected to be placed by the time the entire project wraps up in 2020, said the association's technical director, Sandy Brown. But the project is significant in other ways, he pointed out.
As examples, he cited the use of drones to take construction progress photographs and double echelon paving. Echelon paving is the technique of paving multiple lanes side-by-side, with the adjacent paving machines slightly offset, to improve the longitudinal joint between paves.
In the case of the first phase of Highway 407, however, there were actually four pavers side by side for large portions of the 21-kilometre route along the main line and 10 kilometres on the new Highway 412 which links with Highway 401 to the south.
In other areas, only single echelon paving was feasible.
Brown also touched on the sequencing and the work performed by the two contractors, Coco Paving and Miller Paving. Construction began in May 2012, with paving commencing in the fall of 2014 and then the opening of Phase One to traffic this past June.
Besides the high volume of hot mix asphalt, more than 10 million cubic metres of earth was moved and more than a million tonnes of granular applied. Several interchanges and 62 structures were also erected, he said.
The second stage of the easterly extension was split into two sections. Construction of Phase 2A, which will take the highway from Harmony Road to Taunton Road/Highway 418 has been underway since 2015 and is targeted for opening next year.
In Phase 2B the highway will be pushed to Highway 35/115. This scope of work will also include the building of the new 10-kilometre north-to-south Highway 418, linking Highway 401 with Highway 407 east.
"The pavement design is not yet finalized but it will also be asphalt throughout," said Brown.
The history of the 407 goes back a long way, added Brown.
"Planning started over 25 years ago with the route selection and the environmental assessment," he said.