Stratavault trees growing strong...

Stratavault trees growing strong at Thomson Family Park in Calgary

Thomson Park

Thomson Family Park is a thriving urban park situated in West Connaught in Calgary, Canada. The space was first recognised as a park in 1929, when the site was developed for use as a lawn bowling green. It became home to the heritage listed Calgary Lawn Bowling Club before being redeveloped in 2016. Today, it is a publicly accessible park that provides visual appeal, economic benefits and an abundance of green space to the local community.

Citygreen played a pivotal role in the park’s transformation, working with Ground Cubed landscape architects, EXP Engineering and Alpha Better Landscaping to create a functional, beautiful space that continues to delight the community three years after installation.

Thomson Park


Project goals

Before the redevelopment, the Thomson Family Park site was lacking green space, meeting only 30% of the City of Calgary’s open space targets. When the bowling club moved to a new facility, the City recognised an opportunity to green the area and create one large park. As well as reflecting the community’s desire for a new public space, the project aimed to:

  • Maximise use of the site, while honouring the park’s history
  • Increase shade and air filtration with healthy tree canopies
  • Implement stormwater distribution and retention systems
  • Combine blue and green infrastructure using sustainable solutions
  • Reduce the load of the City’s municipal sewer system
  • Add value to the site and surrounding area


Project solutions and methodology

Citygreen’s Stratavault system was chosen for its ability to maximise soil volume for healthy trees to grow. With its incredible strength and lateral load distribution, Stratavault was also able to support the weight of the sidewalk in this high traffic area – a critical requirement for this project.

Stratavault soil cells were installed by Alpha Better Landscaping along the park’s sidewalk on 11th Street. The photograph below shows the compacted subgrade, with the sub-drain running centrally through the tree-pit. The clean-out for this drain rises through the cells at the end.

Once the Stratavault cells were installed and back-filled with soil, stormwater distribution pipes were positioned at two parallel locations through the upper level of the cell matrix. The large apertures in Stratavault cells made this process easy, with no need to remove any part of the structure.

Thomson Park

The installation was also streamlined thanks the Stratavault’s ability to maintain its structural integrity while removing sections of the matrix. The image below shows how the contractor was able to create root-bole openings to match the position of the rectangular tree grate. The system is still completely connected around the opening, maintaining its strength and integrity, and exceeding the loading standards for downtown Calgary sidewalks.

As well stormwater distribution, the system also facilitates stormwater retention and filters pollutants from stormwater before it reaches the city’s rivers. Rainwater run-off from the roadway is directed through catch basins at the curb and into the soil cell system below the sidewalk, providing passive irrigation for trees.

Thomson Park

Project outcomes
Since opening in 2016, Thomson Family Park has become a popular place to meet, celebrate and relax in Calgary. The trees have grown beautifully through the grates and pavers, producing vibrant green canopies that add shade and visual interest to the street.

The integration of green and blue infrastructure ensures the trees will continue to thrive for decades to come, while also reducing the load of the City of Calgary’s sewer system.

“Great customer service, quick response times and a very in depth QA system with constant support.”

- Laura Wiesenekker, Project Engineer, Densford Civil -

“Citygreen is a very professional  business, and I found everything was great in terms of deliveries, product supply and information. It was all forthcoming and helped us to complete the project.”

- Keith Burns, Architect/Designer, Keith Burns Architect -

“Citygreen offered training and invaluable technical assistance during the works.”

- James Callan, Estimating Manager, Complex Co Pty Ltd -

“Our experience, in working with a Citygreen Design Studio was second to none. We found responses from the design studio to be very timely, and technically thorough. We went backwards and forwards a number of times, looking at different iterations of the design and, nothing was too much trouble to examine and explore different possibilities. I would highly recommend the Citygreen Design Studio to any future client considering using your services.”

- Sandra Smith, Principal Landscape Architect, City Of Monash -

“We are big on compliance on all projects, and the fact that their SmartCertify cloud platform covers all bases, and supports their 20 year warranties, is critical – especially that these pits are being installed under roadways and footpaths.”

- Johny Purkaystha, Civil Program Engineer, Central Coast Council -

"I reviewed all the previous projects that we have installed in the past couple years using your product and I can happily report back that we have 0% mortality in the soil cells, which is incredible!"

- Brendan Wilton, CEO, Trim Landscaping, Bedford, Canada -