Although this week’s demolition of Wacky Wings drew more eyes to downtown Sudbury’s south district, another crew conducted important work at the site of the future arena/event centre.
On Monday, contractors from the firms Marathon and EXP began a week-long geotechnical investigation by digging various holes throughout the future event centre lands.
City strategic initiatives lead Tony Cecutti told Sudbury.com that the investigation builds on past work which reaffirmed suspicions regarding soil conditions.
Prior geotechnical work dug deep to establish the depth of bedrock which the building’s foundation will need to be supported by.
Now that this “bigger hurdle" has been cleared and deep ground conditions have proven to be as expected, this week’s work involves shallow digs, Cecutti said, “to characterize the soil condition throughout the whole site.”
“Every property has a different character of soil, and we need to know whether those soils need to be left or removed and how to manage them, and each site’s a little bit different so it takes quite a bit of work to characterize those shallow soils,” he said.
According to prior geotechnical work performed earlier in the event centre project, bedrock has been determined to be approximately 35 to 45 metres down, which Cecutti said echoes pre-conceived notions regarding soil condition the city had gathered from past reports.
“We’re not finding anything that’s different from our original assumptions when we did the feasibility work,” he said, adding that nothing they’ve learned thus far has bumped the project beyond its council-approved $200-million budget ($225 million including money spent on land acquisition/demolition and the since-cancelled Kingsway Entertainment District).
The foundation will consist of micropiles, which are narrow piles which extend deep into the ground to shore up foundations against bedrock rather than the soft soil above.
Although piles are often thumped into the ground by heavy machinery, the micropiles for the event centre will be screwed in to create less vibration for adjacent buildings.
Junction Creek and Nolin Creek run through downtown Sudbury and have historically left soil deposits of varying consistency throughout the region.
“With those soft soils, it’s not practical to put a floating slab on top of those soils, so you need to drive piles down to support the foundation,” Cecutti said.
Next up for the event centre project will be the presentation of architectural drawings to city council sometime in early autumn, Cecutti said, which will take place in concert with ongoing public engagement to get feedback.
“We’ve had a lot of very constructive dialogue with stakeholders,” he said. “We’re looking forward to sharing what we’ve learned, what people feel is important and how we’ve incorporated that into the design of the facility.”
Tyler Clarke covers city hall and political affairs for Sudbury.com.