Stratacells extend Elm life in Edmonton

Stratacells extend Elm life in Edmonton

By Kristyn Levis

99 Street Plaza

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A very old American Elm in the City of Edmonton in Canada, valued at around $25,000, has been given a new lease in life with the help of the Citygreen® modular Stratacell™ system.

The 99 Street Plaza project was designed in 2013 as part of a larger streetscaping project. The small plaza was essentially a sidewalk/boulevard project aimed at improving the existing sitting node adjacent to a neighbourhood café.

Jim Black, the project’s landscape architect from the City of Edmonton, said the old site was a 1.5 metre sidewalk with a three-metre wide hard packed gravel boulevard. In the gravel boulevard stood a 150mm caliper Brandon Elm and a very old 500mm diameter American Elm.

stratacell installation

“It was a great concern to the city and within the community that it be saved and, if possible, its environs improved. The community desired that the concrete walk and gravel be removed and replaced with a hard surface area for café tables. At the same time, it was recognised that this could reduce oxygen/water penetration to the roots,” Black said.

A design using Citygreen’s Stratacell system beneath a permeable paving stone surface was developed. Black said the system allowed the introduction of topsoil to the root area and the permeable blocks allowed penetration.

99 Street Plaza project in Edmonton

Kevin Donaghey, project manager at SG Landscaping, said the streetscape upgrade involved the installation of bollards, decorative poles, two patio areas and related site furnishings. The project costs around $400,000 with some items ready for completion this Canadian spring. The Citygreen system was used under pavers in high traffic areas where tree plants are in close proximity.

“There was some judicious root cutting on one side of the elm, but it was felt that regrowth of roots into the improved growing medium would quickly compensate and over time, these roots would be able to colonise a much larger topsoil area,” Black said.

The trickiest part of the project was setting the ground elevations to accommodate drainage while minimising depth of excavation.

“There was some hand digging and exposing of larger roots. We have funneled much of the surface water in the area toward the permeable pavement,” Black said.

Since the project is still fresh, there hasn’t been time to evaluate the effect on the trees. However, Black is confident it’s all going to turn out as planned.

“Our experience with similar excavations are that the construction damage to the roots was within tolerable levels and the improvement to the growing medium will give this tree an advantage that similarly impacted trees in the past did not have,” he said.

stratacell installation in the 99 Street Plaza project

He found that the cells were straightforward to install and “within budget on a cost benefit basis”.

Donaghey echoes the positive feedback with using the Citygreen system, finding the installation quite simple. The presence of a Citygreen representative prior to the start of the project to discuss installation methods with the crew also helped make the process much easier.

“This system is much better than similar fabric-type systems as it is easier to install and fill with soil and in my opinion, a stronger system overall,” Donaghey said.

99 Street Plaza project

“The biggest issue with the project was getting site furnishing delivered on time and having the suppliers live up to their word on delivery. The Stratacell was the only product we used that was delivered on time,” Donaghey said. He is very positive about using the system again in future projects.

Although he added that material cost is a bit higher, the labour involved to install the product is cheaper. “With the high cost of labour here, overall it was a little cheaper,” he said.

“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 -