The Bay Area’s housing crisis isn’t just straining residents’ wallets. According to a new study from UC Berkeley and the California Housing Partnership, it’s resegregating cities, displacing minority communities and exacerbating historical patterns of racial and ethnic inequality.

The researchers found that communities of color are particularly vulnerable to rapid increases in rental and housing prices. Since the Bay Area has experienced consistent, dramatic spikes in the cost of housing since the end of the Great Recession, it follows that these communities have been hit the hardest by the housing crisis.

But the study lays out a startling portrait of how high the costs have been for these communities — and how quickly they’ve transformed the Bay Area.

“A 30 percent tract-level increase in median rent (inflation-adjusted) was associated with a 28 percent decrease in low-income households of color,” wrote Philip Verma, Dan Rinzler, Eli Kaplan and Miriam Zuk, the report’s authors.

This report, covering most of the Bay Area from 2000 to 2015, builds on a study the same authors released last fall examining the counties of San Francisco, Alameda and Contra Costa.

With affluent white residents increasingly attracted to life in the Bay Area’s urban core, lower-income African Americans, Latinos and Asians are increasingly clustering on the fringes of the Bay Area.

Exurban outposts are particularly difficult for these communities. They typically have fewer social services to combat poverty and its related ills. They also tend to have far less transit infrastructure than cities do, isolating residents from educational and work opportunities.

Densely built cities don’t just provide more opportunities to improve one’s educational and work history — they also make it easier to create and maintain support networks for hard times. There’s even evidence that they improve lower-income peoples’ life expectancies.

A region that only works for a select few means that everyone pays, whether it’s in the form of traffic congestion or social cohesion.

Combatting these trends will require a multifaceted approach.

State and regional policymakers have a big role to play.

First and foremost, they must pass and enforce legislation that increases housing production, especially for lower-income residents, in the state’s hard-to-build cities. They must also explore ways to create opportunities for newly arrived communities in far-flung districts. Finally, they must find ways to shore up the region’s new CASA compact against local resistance.

At the local level, cities should consider partnering with suburban districts on transit and educational planning in support of lower-income residents. If crisis can push some residents away, leaders must guide opportunities back in their direction.

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