DIVERGING DIAMOND INTERCHANGE
adopt and adapt best practices from the United States and Europe for implementation in Calgary’s local context.
Location: Calgary, Alberta
Project Type: Transportation
About This Project
In 2014, Calgary City Council approved funding for a new interchange at this
location and The City of Calgary enlisted the help of ISL to plan, design and construct the most suitable interchange configuration.
Following a rigorous evaluation and community engagement process, the Diverging Diamond Interchange (DDI) configuration was selected as the functional design for this location because it enhances mobility for commuters, transit users and cyclists; increases access to surrounding businesses and services; and allowed for innovative construction staging that avoided major detours and accommodated active modes of transportation.


at lower cost and in less time than a traditional interchange.
The opening of Canada’s first DDI was achieved because of the close collaboration between The City of Calgary, ISL and Graham Infrastructure. For The City, the decision to build Canada’s first DDI at Macleod Trail and 162 Avenue was based on several key criteria including increased safety, improved capacity and ease of construction. Exploring current practices of DDI design in the US, the DDI design by ISL was developed with Calgary’s unique context in mind, considering site specific conditions, driver behaviour and climate. The opening of the interchange in August 2017 was widely praised by users, City officials and in media coverage that brought national and international attention to Calgary for its innovative, forward-thinking approach to transportation design.
What is a DDI?
To help stakeholders visualize the configuration from the street level and understand how the DDI works, ISL called in the support of its in-house 3D visualization team who worked with The City to develop 3D renderings and animation.
Integrated Expertise
- Transportation Engineering
- Municipal Engineering
- Structural Engineering
- Supporting Services