Designed to eventually house 30,000 residents, the Blatchford development is intended to be a sustainable mini-city within the heart of Edmonton. Image: City of Edmonton

Remediation efforts clear way for Edmonton's Blatchford development

As the first licensed airfield in Canada, Edmonton City Centre Airport was a point of pride for the city when it opened in 1929. By the time it officially closed for good in 2013, it had become a political nightmare. 

For years, the underused and aging site had been an anchor on the city’s downtown ambitions because of the height restrictions it imposed on buildings in the area. Yet the facility still held some value for smaller aircraft, including medevac services that took advantage of the airstrip’s close proximity to the Royal Alexandria Hospital. After years of debate, a brief stint as a race track, and much speculation on potential uses for this valuable plot of land, the airport was finally shut down and the way cleared for a massive sustainable community development: Blatchford.

All that will remain of the historic airport will be its control tower. According to Mark Hall, executive director of the project for the City of Edmonton, the structure will be upgraded and eventually serve as a community space. During development, it will provide office space for contractors, while prospective tenants can look forward to a trip to the top to view their future homes. Located on the central spine of the project, the tower will serve as its signature feature.

“This is an overused word, but it’s iconic,” Hall says. “You cannot misunderstand the original purpose of that building when you look at it.”

Designed by a team led by Perkins + Will, Blatchford has been racking up numerous honours, including a National Urban Design Award in 2014 from the Royal Architectural Institute of Canada (RAIC). The prize was not simply a recognition that the designers had repurposed a challenging, underutilized site, but that they had also provided the city with a model for a new generation of more sustainable development.

“This is urban design at its broadest and fullest: the creation of a framework that will allow a generation of architects, landscape architects and engineers to contribute to the building of Edmonton,” the RAIC judges note.

The judges are right. With a price tag of $740 million over its 20-year development cycle, Blatchford is undoubtedly a once-in-a-generation project for the city. Offering space for 30,000 residents and 12,000 dwelling units, it will be a miniature city carved out in the centre of Edmonton, with everything from offices to commercial space to schools. The ultimate goal is to create one of the largest sustainable community developments in North America—pedestrian friendly, connected to transit and 100 per cent carbon neutral.

Solar panels will help the project decrease its reliance on Alberta’s still carbon-intensive grid, while a district energy sharing system will be crucial to lowering power demand at the site. Office buildings, packed with people, computers and lights, generate excess heat that can be captured and used to warm residences, reducing energy use at the project by 15–20 per cent. Shallow geothermal energy will be tapped through geo-exchanges under Blatchford’s stormwater ponds, where heat can be transferred to buildings in winter and stored underground in summer. Additionally, a sewer heat exchange will warm and cool buildings by transferring thermal energy to and from wastewater.

Hall notes that the city will need to work with builders on the site to establish sustainability standards as houses, offices and schools begin to go up. The project will likely aim for energy intensity standards that exceed the current Alberta building code in order to ensure Blatchford stays ahead of the curve. The city will also look at various site management tools that can increase construction efficiency as multiple contractors start working on the site.

For now, remediation and site preparation are still ongoing as the city aims to be ready for the first wave of residents in 2017. Two phases of remediation work—encompassing eight sites and 24,348 tonnes of soil—have been completed for $1.6 million, which is well below the originally budgeted $3.5 million. In total, there are 15 sites that will ultimately need to be remediated.

So how is the project keeping its cleanup costs so low? Hall credits years of extensive testing as a major factor: the city has drilled over 180 holes on site to ensure it has an accurate picture of the challenges that lie ahead. He also acknowledges the generations of workers at City Centre Airport that made efforts to keep petrochemical pollution to a minimum.

“There were lots of stories about the site being grossly contaminated, and it’s the farthest thing from the truth,” he says. “When you consider what went on at that site and for how long it was going on, it’s remarkably clean.”

As soil is trucked away for remediation, the project will use dirt from the stormwater pond excavation to complete site grading. “The key on all of that is that we’re trying to handle this material once,” Hall says. “We don’t want to pick it up and move it from point A to point B and put it at point C and then put it in its final place. Double handling and triple handling material is very expensive, so do it once.”VIEW02 Dirt excavated for Blatchford's stormwater pond will be used to complete site grading and replace the over 24,000 tonnes of soil that have been removed so far for remediation. Image: City of Edmonton

A number of old buildings will need to be cleared out before new construction can begin. However, Hall cautions against calling this a demolition job. It’s more of a recycling effort. Five buildings so far have been dismantled and re-erected elsewhere, and doors, windows, wires, lighting fixtures and other components will be reused from others. The city’s goal is to divert 85 per cent of the waste from landfills. So far, it is beating that goal with a 92 per cent diversion rate.

The final recycling challenge posed by the old airport is the runway. Somewhere between 25 and 30 per cent of the Blatchford site is covered in tarmac. The project has already begun accumulating a sizable stockpile of gravel, asphalt and concrete that will be used in building streets on the site, or sold to other contractors around the city.

“I was talking to a guy in the construction industry, and he was telling me that one of his suppliers goes to Onoway for gravel,” Hall says. “Next year, come to Blatchford and we’ll get you a truck-load of gravel.”


2015 ACM MMM Button

2015 ACM Email Button

Login

Free account to gain access to ACM digital editions.