A bundle of three studies on the housing markets in Alameda County, Contra Costa County, and San Francisco, California released by the Urban Displacement Project (UDP) reached the same conclusions on the consequences of housing unaffordability in California: segregation is worsening.
Between 2000 and 2015, as housing prices rose, the City of Richmond, the Bayview in San Francisco, and flatlands areas of Oakland and Berkeley lost thousands of low-income black households. Increases in low-income black households during the same period were concentrated in cities and neighborhoods with lower housing prices and fewer resources…
Low-income households of color were much more vulnerable than low-income white households to the impact of rapid increases in housing prices. In the Bay Area, a 30% tract-level increase in median rent paid between 2000 and 2015 was associated with a 21% decrease in low-income households of color but no change in low-income white households…
Upon moving, a significant share of low-income people of all races not only left their county of origin but left the region altogether. For example, 40 percent of low-income black households in Alameda County who moved in 2015 left the Bay Area, another indication of regional displacement pressures.
Minority residents are particularly rent-burdened (defined as spending more than 30% of income on housing costs) relative to their white peers, though this effect diminishes among higher-income minorities.
The reports also found that those who are displaced and move to lower-rent neighborhoods tend to move into areas with poorer job market opportunities, sometimes forcing them to spend much more time and energy to commute to work. There is also a lack of healthcare facilities in these neighborhoods.
While none of the three reports explicitly cites zoning or land-use regulations as a cause of the crisis, there is a wealth of evidence showing the link between housing affordability and regulatory stringency. Additionally, low-quality housing conditions and poor treatment by landlords are additional symptoms of restricted supply, as a lack of housing options gives renters little bargaining power relative to the property owners.
You can find all three of the reports (Alameda County, Contra Costa County, and San Francisco) and other research related to segregation and housing regulation in our reference library.