CALGARY and TORONTO -- Sipping coffee in a spacious Calgary bungalow, Sandra Horley is a long way from home. The single mother of two lives in Forest Lawn, an east side neighbourhood considered among the city’s most challenged. Car-less and often without bus fare, the 43-year-old, who depends on social assistance, gets around mainly by foot.

But for the purposes of our discussion, Horley has agreed to meet at the tidy suburban cul-de-sac on the other side of town, where her kids’ elementary school principal, Jean Johnson, lives. The area’s manicured lawns are a world apart from her hardscrabble community, and yet, when it comes to gauging Calgary’s economic disparity, Horley says the distance between here and Forest Lawn is not the one that matters most.

“In Calgary, I see it like this,” she explains, opening her arms like an alligator’s jaw. “You have your wealthy,” she says, glancing up at her top hand, “and then you have your middle class and your poor, and they’re down here. Because of the oil industry in this province and in this city, there is a big discrepancy here.”

Simplistic though it may seem, the evidence is mounting that Horley’s assessment isn’t far from fact.

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Calgary was built on possibility and an ingrained belief that success is available to all those who seek it. But from 1980 to 2005, the gap between rich and poor neighbourhoods deepened dramatically. While the region roared into a period of unprecedented prosperity, Census data show that the income differential between have and have-not communities (measured with the Gini coefficient, using after-tax values) grew by 81 per cent -- far more than any other urban centre. The increase was enough to vault Calgary over Toronto, giving “The Heart of the New West” the dubious distinction of leading the country in neighbourhood income inequality.

According to University of Toronto sociologist John Myles, who crunched the data in a 2011 working paper titled “Why Have Poorer Neighbourhoods Stagnated Economically, While The Richer Have Flourished?”, the shift was caused primarily because “the rich were getting richer.” Over 25 years, the mean after-tax income in Calgary’s poorest neighbourhoods inched up by a mere five per cent; in the richest neighbourhoods, meanwhile, that figure ballooned by nearly 75 per cent.

None of this comes as a surprise to Noel Keough, an urban design professor at the University of Calgary, who has tracked the issue of income inequality in the city since the ’90s. As for the root of the disparity, he, too, points toward the collection of gleaming corporate headquarters clustered downtown.

“The oil and gas sector earns significantly higher [incomes] than any other sector, and it’s a minimum of people that work in oil and gas,” he says. “The concentration of a single industry with large, multinational players concentrates the wealth that’s generated in our city and in our province.”

Keough highlighted the degree to which the bounty has been increasingly flowing into the pockets of the few in a recent report he authored for the non-profit Sustainable Calgary. In 2005, he noted, the top 10 per cent of Calgary families earned 37 times as much as those at the bottom, which represents a 13 per cent increase in the gap since 2001.

At the time of the last Census, 14 per cent of people in Calgary were living below the low-income cut-off, which was slightly below the national average. But a recent survey of the concerns of Calgarians suggests that many more are struggling: almost one-third of respondents worried about housing costs; a fifth, meanwhile, said they were anxious about having enough money to put food on the table.

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Yet as the city grows, there’s a sense that these issues -- however prevalent -- are becoming increasingly hidden.

“You honestly can live in your world and never see it,” explains Johnson, who says that the communities that have sprung up in recent decades, “are not really subdivisions so much as they’re like little satellite [cities].”

But as the gulf widens between the myth of Calgary and the reality of many who live here, some blame pride in place for obscuring the social and economic consequences of the deepening divide, which they say is taking a toll on everything from household balance sheets to neighbourhood schools.

“Calgary likes to think of itself as the communal best, richest, biggest, newest, etc.,” says Dan Meades, the director of the non-profit Vibrant Communities Calgary. “It is hard to feel that way if we also confront the fact that so many people are poor.”

It’s a tension that helps to explain why, in a land of plenty, it can be even tougher for those who are left behind.