The urban revival of the past decade has been nothing short of remarkable. Young, affluent, highly educated people have flowed back to downtown cores in cities like London, New York, San Francisco and Vancouver. Good jobs, better restaurants, higher tax revenues and even high-tech startups have followed.

But this dramatic back-to-the-city movement also has its dark side, giving rise to what I call the new urban crisis, which registers itself in increasingly unaffordable housing and a growing divide between rich and poor.

Housing in Vancouver may not be as expensive as cities like London or N.Y. But, the rule of thumb is that an affordable house should cost roughly three times your gross household income. With few detached properties now available for under $1 million, the average Vancouver home adds up to a whopping 12 times the average salary.

Such expensive housing hits low-wage blue-collar and service workers hardest. Across Canada, these workers have just $26,400 and $11,500 left over after paying for housing compared with knowledge, professional and creative workers who have $45,000. It’s hard to run a city when service workers can’t afford to live there.

Vancouver’s wealthiest one-per-cent earn roughly 11 1/2 times as much as the average resident, up from seven times in 1982. The city’s inequality today is on par with Russia or Ghana.

Rising inequality in Vancouver is driven by the decline in stable, blue-collar, middle-class jobs, which make up just 15 per cent of the region’s jobs. Highly paid professional, knowledge and creative jobs make up 36.5 per cent of jobs, while lower-paid service jobs account for 47 per cent of jobs.

Vancouver is seeing not just the decline of its middle class, but of the neighbourhoods such families called home. Middle-class areas, which made up more than 70 per cent of Vancouver neighbourhoods in 1970, have fallen to less than half by 2005, the last year for which data is available. There are likely far fewer today.

As the educated and affluent flock back to urban cores, a great deal of poverty in cities like Vancouver has shifted to the suburbs. Indeed, these places are morphing into a new kind of “patchwork metropolis,” with small areas of the advantaged concentrated downtown near subway and transit stations or in affluent suburban areas, surrounded by much larger spans of concentrated disadvantaged.

The new urban crisis has engendered a backlash that resulted in the rise of the late mayor Rob Ford in Toronto, the Brexit in Britain and Donald Trump in America. Vancouver has been spared its worst consequences so far. But, it’s imperative that Metro Vancouver address the crisis if it hopes to keep populist backlash at bay.

Prime Minister Justin Trudeau campaigned on reducing inequality, rebuilding the middle class, investing in infrastructure and generating more affordable housing in Canada’s cities. But Vancouver must also be proactive by increasing density, building more affordable housing, turning low-wage service jobs into family supporting employment and investing in better transit.

Despite the deep divides and challenges they face, New York, Los Angeles and San Francisco are at the front lines of the opposition to Trump. The conflicts brewing in these cities over the big issues of inequality and housing affordability — over the nature of place itself and who has access to it — are forcing a new breed of progressive mayors like New York’s Bill de Blasio, L.A.’s Eric Garcetti and London’s Sadiq Khan to confront and develop new strategies and solutions to the new urban crisis.