Innovative paving technology benefits environment and bottom line in Durham Region

An innovative paving process that reduces the materials needed while improving the bond between asphalt layers has earned the Region of Durham ‘Municipal Paving Project of the Year’ honours at the recent Ontario Good Roads Conference.

Durham Region, in partnership with Road Surface Recycling Limited, developed a pilot project for road rehabilitation using Hot-In-Place Recycling technology (HIR) that worked so well on the two initial test locations – four kilometres of Shirley Road in Scugog and 4.2 kilometres of Highway 2 in Clarington – that it allowed crews to add two more locations to the contract.

The costs incurred were “lower than expected,” which enabled the region to add a 2.2-kilometre road segment on Lake Ridge Road in Brock Township and the access road and parking lot at the Waste Management Centre on Garrard Road in Whitby.

“Durham Region continues to adopt and test new technologies like HIR to learn what works best in real-world conditions, to reduce our carbon footprint and meet our climate goals,” said Dan Waechter, Durham Region’s Director of Capital Projects Delivery. “The lessons learned here will inform design and specifications for future projects. This award from Good Roads recognizes Durham Region’s leadership in piloting new approaches within this industry.”

The Hot-in-Place Recycling technology was tested to see if it would repair asphalt, extend the life of the road and reduce waste, with “challenging” road segments chosen for the pilot to “test the limits of this method,” Waechter said.

The approach uses heat to create natural bonds between the layers of the asphalt to help reduce water infiltration, potholes and cracking during the frequent freeze-thaw cycles experienced in Canada. With this process, the volume of aggregate material typically mined and trucked in for road construction, are “significantly reduced,” lowering costs and reducing the environmental impact.

The process included six integrated steps: pre-heating, gradation adjustment, hot milling, asphalt cement rejuvenation, mixing and relaying.

For this project, a one-metre shoulder widening was added using oxidized crushed RAP imported from an asphalt plant, which is the first time this was done in an Ontario paving project.

The method can be repeated for future rehabilitations on the same roadway by continually recycling the aggregate and restoring the asphalt and no pavement waste was generated during the pilot, as all existing aggregates and asphalt cement were fully recovered and reused. Other benefits of the process included faster resurfacing and with minimal traffic disruption, reducing the time and money required for rehabilitation work with less inconvenience to motorists.

“A huge congratulations to our award-winning Public Works Capital Projects Delivery team – true professionals who work tirelessly behind the scenes to deliver the core services we rely on daily,” said Oshawa Regional Councillor Tito-Dante Marimpietri, who sits on the region’s Works Committee. “The recognition for their innovative environmental pilot partnership in advanced asphalt road resurfacing hot-in-place paving services is a testament to their leadership, expertise, and commitment to excellence.”

Good Roads, a municipal association that has been focusing on the quality and design of roads in Ontario since 1894, recognize successful municipal-private sector collaborations for excellence and innovation in paving projects each year.

Oshawa Councillor Tito-Dante Martimpietri with Durham Region Chair John Henry at the Ontario Good Roads Conference