Risk analysis models on Calgary’s Green Line transit showed the city would run as much as 10 per cent over the $4.9 billion budget on the megaproject, according to the Calgary’s Transportation general manager.

Those calculations, based on the current Green Line configuration with a single bore tunnel, are the lynchpin behind a review on the portion of the proposed stretch that runs from 16 Avenue North and Ramsay.

Michael Thompson, GM of Transportation, told LiveWire Calgary that after first running so-called Monte Carlo simulations, first at P80 (project delivered at the budget or below 80 per cent of the time), it was run at the more conservative P90 level.

“And so, if we look at that, and we look at where we were, we’re running about 10 per cent higher than our affordability, our budget, which is $4.903 billion,” Thompson said.

Later clarification from the city’s transportation department confirmed that those simulations were showing the project over budget by between $300 million and $500 million at the P90 level. They added that those kinds of budget overages are typical to see at this stage in a project.

Tunnel under Bow the big concern

It comes down to the tunnel and some of the unforeseen challenges that arose during their investigation. Ultimately, Thompson said going with a single bore tunnel pushed the station depth to as much as seven storeys. He said that didn’t meet the city’s vision for a low-floor, accessible transit system.

“At the same time, our risks that we were hoping to mitigate with a single bore tunnel, we were mitigating some risks, but we’re bringing on other risks,” he said.

“That’s where we’re at right now… we need to look at how do we raise the depth of that tunnel through the downtown, make it shallower.”

A bridge over the Bow River, instead of tunneling under it, and then a shallower depth in the downtown with a possible ‘cut and cover, below-grade model could help the city achieve the necessary cost savings to keep the project in line with budget expectations, Thompson said.

Geotechnical concerns in the river valley

Thompson said they’d done some budget accounting for different geotechnical conditions that might arise in the downtown, but when cost and risk kept growing, he said they felt it was time to revisit the plan.

“There’s an underground, an old river valley that runs through the centre of downtown, so there’s varying geological conditions underneath downtown,” Thompson said.

“There’s a high water table downtown. We’ve done analysis of that. So, we understand it. And there’s ways to mitigate all of this. But at the same time those are engineering solutions. They’re still risky.”

Thompson said if they’d been closer to the vision the city set out for the accessible Green Line, they may have tried to push forward with the current plan. Right now, he said the vast majority of risk lies in the tunnel portion of the Green Line.

“But as we look at the costs being higher, the risks being higher, not meeting the vision. That’s where we said we should just step back on the downtown and go and talk to people again about it,” Thompson said.

Green Line transit stage one is ready for RFQ

Thompson said they have the majority of the land assembled for the southern portion of the Green Line, from the Elbow River to 126 Avenue SE, and they’ve moved utilities and landfills in order to expedite construction.

They’ve also split the contract in two; one contract is for the northern portion and another contract is for this southern portion. Thompson said they can still continue the technical review on the downtown portion while making preparations to get big shovels in the ground on stage one by the end of 2020 or start of 2021.

Earlier this month, the Beltline Neighbourhoods Association (BNA) said the entire project should be paused until the downtown and northern portion is settled. Any cuts to the Green Line should be shared along the entire proposed route to ensure that attention was given to doing the downtown portion properly, they said.

“In the face of uncertainty with further cost reductions and alignment changes in this area it would be irresponsible to proceed with construction in southeast,” BNA President Peter Oliver told LiveWire Calgary at the time.

Community outreach happening

Thompson said they’ve been able to talk with some of the community associations and area stakeholders about the challenges they’ve encountered and where they’ll go next.

“We think the strategy we have does both of those and allows us to push that piece that’s ready for right now, while spending the time to look at the planning for the piece we need to spend some more time on,” Thompson said.

“And it gives everyone assurance that by the end of 2026 for the full stage one project.”

Councillor Evan Woolley has an urgent notice of motion in place to be discussed to “reset” the Green Line project.

Woolley is suggesting the city work with an independent third party for the review of both the contracting strategy and to review the risks associated with alignment decisions that could negatively affect downtown real estate.

“I worry the Green Line may be reduced from an investment in Calgary’s global future to a project that is a burden to taxpayers, doesn’t serve the downtown and is a train to nowhere,” Woolley said at the time.

“I will not risk our city’s stressed finances, or the fragile recovery of business in the downtown, without assurance that we’ll get an end result that serves Calgarians.”

Alignment changes unlikely for Green Line transit project

Thompson admitted that it’s possible council could ask them to revisit other alignment options, but he didn’t think it was likely.

“We’ve looked at a lot of other alignments over the years. We’ve got reports going back to council from a number of years ago, looking at different alignments and different options,” Thompson said.

“And through a process that we worked with tens of thousands of Calgarians, we came up with the options that we have right now. We’re committed to delivering that option and doing it while be financially responsible.”

Thompson said they take their direction from council. If the pause prompts some councillors to push for revisiting the staging and alignment, they’d happily take it on.

The proposed Green Line route. CITY OF CALGARY

One of the areas of division is around ridership projections. Some members of council and the general public are using the pause as an opportunity to foist the ridership angle back into the discussion. Thompson said they expect 60,000 to 65,000 people riding the south portion when Green Line transit opens. He compared it with only 30,000 for the west leg of the LRT.

“There’s always been interesting discussions about ridership in the self to ridership in the north,” he said.

“The reality is both have really strong desire lines for transit ridership into the downtown, and not only into the downtown, but connecting the services and the places along the route. And so when we did this, we weren’t just looking at a line haul into downtown, we are really looking at connecting community amenities, and bringing people together to the places where they want to go.”

Next steps forward for the Green Line transit

Back in 2016, city council was forwarded dozens of letters in support of the current alignment, especially as it pertains to the tunneling option. Thompson said over the next few months they’ll be re-opening discussions with these groups to share what they’ve learned about the tunnel option.

By January 2020, Thompson hopes to have a plan in place to move forward with contract one – the south portion.

He doesn’t want to presuppose any opposition to potential changes. He said they’re going to establish the dialogue and go from there.

“Where we go to, I think that we’re aligned with a lot of people around and are focused on delivering the vision that we’d all established together. We just don’t think that where we were getting to was going to establish that vision. And so that’s why we said we should pause, take another look at it,” he said.

“It’s not an easy thing to say let’s pause for a project and take another look at it because we don’t think we’re meeting the vision. But I think it was the right thing to do.”

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