Highway 407 East

Ontario, Canada

Air quality, noise and vibration assessments for a 46-kilometer highway expansion

Highway 407 is a major artery in Southern Ontario, running east-west above the northern edge of Toronto. In 2012, the Province broke ground on a substantial expansion of the highway, planned to roll out in stages over the next eight years. One part of the project will extend the 407 itself eastward from Brock Road in Pickering to Highway 35/115 in Clarington. Two new north-south routes will connect the new stretch of 407 with the region’s other key east-west traffic artery, Highway 401. 


  • The Challenge

    This work will add a total of 46 kilometers to the area’s highway network. It represents Ontario’s most substantial highway construction initiative in several decades. The Province’s Ministry of the Environment, Conservation and Parks approved the project in principle in 2010, making it subject to strict environmental conditions.

    In order to proceed, the project required significant air quality, noise and vibration studies and mitigation plans. The highway extension was subject to both federal and provincial environmental assessments (EAs), as well as extensive community consultations in Durham Region. Because of our depth of expertise in noise and air quality assessments specifically related to express highway projects, the Ontario Ministry of Transportation, a long-standing client, engaged us to support the 407 East’s environmental work for both the provincial and federal governments’ EA processes.

    Once the EAs were completed and approved, the design/build team engaged us to help them meet the conditions of approval related to noise and vibration, including fine-tuning noise mitigation measures and monitoring air pollutants during construction. We also assisted with potential snowdrift issues by completing a snow study and proposing mitigation strategies.

  • Our Approach

    Our staff have extensive experience working with interdisciplinary teams of transportation consultants on major infrastructure projects, and were thus well positioned to meet the sometimes fast-changing needs of the highway’s planners and builders--from environmental assessment through design and construction.

    At the EA stage, we developed a customized approach that enabled us to present air quality and noise modelling predictions over the entire project area, using contour plotting techniques.

    As design and construction work have proceeded, our noise and vibration specialists have responded to design changes, rapidly analyzing and proposing adaptations for the noise implications of emerging design choices. We have helped the highway’s builders address numerous noise-related concerns without causing any delay in construction.

    Our air quality team has also carried out ongoing monitoring work, providing air quality data to assist the constructors in minimizing impacts on neighbouring communities during construction.

  • The Outcome

    Our work helped the 407 East project to meet the rigorous environmental requirements of two levels of government and earn approval to proceed with construction. During construction, we helped the design/build team meet their conditions of approval and ensure an environmentally sound project.

    Today, as detailed design and construction progress, we continue to support the team in refining noise controls, and monitoring construction emissions. The project is on schedule to be completed in 2024.