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This city reduced homelessness to near-zero, thanks to big data

Collecting personal information helps identify specific needs — in Bakersfield, California and elsewhere.

By Hanna Merzbach

On the streets in Portland, Oregon, a rainbow of tents litters the sidewalks near downtown and under bridges. People live without access to toilets, basic hygiene, or garbage pickup in the city now viewed as a poster child for homelessness on the West Coast. As of January, over 5,000 people were homeless in Multnomah County, which covers the city of Portland — where housing costs are high and shelter space is sorely lacking.

It’s a story repeated across the U.S., which has more than a half-million homeless people. But recently, a handful of cities have managed to turn things around. In Bakersfield, California, home to 380,000 people, the number of chronically homeless people dropped from 238 to 3 over the last six years — making Bakersfield one of the first cities in the nation to functionally end homelessness.

Bakersfield officials attribute that success to Built for Zero, an initiative that aims to reduce homelessness to near zero. It takes a data-driven approach to what has been an intractable problem. The program is based on the idea that the more you know about the homeless people in a city — down to, in many cases, their birthdates and Social Security numbers — the more you can direct them to the specific services they need.

Since 2015, 100 communities have signed onto Built for Zero nationwide. Portland joined in late 2021, and advocates have high hopes for the program. Sharon Meieran, a Multnomah County commissioner, says it’s a good fit for Portland, with its population of 650,000. “We’re still at the size where this is doable, where we could know who people are so we could serve their needs,” she says.

But Built for Zero has its critics. Some question whether good data will really be enough to solve a worsening shortage of housing nationwide. And some wonder whether the loss of privacy that comes with collecting all that data is an acceptable price to pay.

Since 2005, all communities receiving federal funds for homeless services have had to count the number of homeless people there, at least once every two years, in January. But many who work with homeless people think the federal numbers represent a severe undercount. On a cold January night, many people find refuge away from plain view. Certain groups — like youth — may be hard to track down.

So, in 2015, a New York-based nonprofit called Community Solutions developed Built for Zero, an effort to fill the gaps by drawing on existing database information, adding person-to-person outreach on the ground, and inviting a range of agencies to contribute.

Communities often struggle to reduce homelessness because no single agency is accountable for the entire problem, says Aras Jizan, a data expert at Community Solutions. Each service organization may work on a piece of the problem — such as youth or veteran homelessness — without looking at the entire picture. Joining Built for Zero helps unite city and county leaders around a common goal, Jizan says.

“Having been homeless, I think the one thing I remember most was being invisible. You don’t have a name.”

Denise Brock, case manager for a housing nonprofit in Bakersfield, California

Each community can choose what information to collect, but the lists typically include names, Social Security numbers, dates of birth, and other demographic information. Communities then use the data to find housing for specific groups of homeless people, targeting the needs that are most acute in their city. Some communities focus on veterans. Others target chronically homeless people (those who have experienced homelessness for at least a year and have a disabling condition, such as addiction, mental illness, or physical disability).

Supporters say building this list gives workers a chance to ask homeless people what they need, and the data helps communities create tailored solutions for specific groups and track progress. In Bergen County, New Jersey, for instance, identifying the people with the highest needs allowed city officials to prioritize them for long-term rental vouchers.

Fourteen participating communities across the U.S. — including Rockford, Illinois, and Chattanooga, Tennessee — eliminated homelessness for at least one group, such as veterans.

“Building a single source of truth for tracking progress towards reducing and ending homelessness is pretty crucial,” Jizan says. “Absent that, often we see communities really spiral into discussions about whether or not they’re making progress.”

Bakersfield joined Built for Zero in 2016, when the city had 238 chronically homeless people.

The project’s leaders started by making sure every agency was using the same definition of chronic homelessness, which allowed the project to better target its efforts. The leaders also created a unified command center dedicated to trying different techniques to combat homelessness, and trying them fast.

By zeroing in on chronically homeless people, Bakersfield leaders learned that many of them didn’t want to apply for housing, because they had gone through the application process before and been rejected too many times. So the local housing authority started leasing units from landlords, then subleasing them to people in need, eliminating the application process altogether.

In 2019, Bakersfield leaders also used a grant from the health care company Kaiser Permanente to fund a new government role focused exclusively on finding units and landlords that would allow formerly homeless tenants. Leaders then started going through the regularly updated list of chronically homeless people and matching them with units.

Built for Zero’s goal is for all its participating communities to achieve a status of “functional zero” for homelessness. With chronic homelessness, “functional zero” is defined by having three or fewer chronically homeless people or 0.1% of the most recent January count, whichever is greater.

Anna Laven, who leads the Bakersfield-Kern Regional Homelessness Collaborative, says this doesn’t mean people in the community will never experience homelessness again, but that the experience will be rare and brief.

That means some people are still temporarily homeless in Bakersfield. The problem became more visible with the COVID-19 pandemic and subsequent spike in housing prices. As of November 2021, while the chronically homeless population in Bakersfield was still at functional zero, 463 people were experiencing temporary homelessness — a rise since mid-2019. The community’s database showed spikes in homelessness among elderly people and youth. Laven says leaders can use what they learned addressing chronic homelessness to target those groups next.

Meanwhile, in Portland, Built for Zero has met some resistance.

Some worry about privacy concerns if governments have lists of everyone living unhoused. If the data were shared with police, for instance, it could be used to sweep camps, critics say. One former city official, speaking to the news outlet Willamette Week, warned that data can be abused, and compared recording homeless people’s names to the actions of the Nazis during the Holocaust: “There are too many instances of people ending up on lists and bad things happening to them.”

Jizan, from Community Solutions, says police across the country have never used the Built for Zero data. Federal privacy laws limit its use to providing services, creating de-identified client records, administering the program, and making payments for services. In all participating communities, each homeless person gets on the list only after workers get their consent and tell them why the data is being collected and how it will be used.

In “The Way Home,” a documentary series released in 2020 on several streaming services, one formerly homeless Bakersfield resident was supportive of using data to tailor housing solutions. “Having been homeless, I think the one thing I remember most was being invisible. You don’t have a name,” says Denise Brock, who now works as a case manager for a local housing nonprofit that is part of Built for Zero.

Still, privacy and ethics risks are always associated with creating a database, says John Basl, a philosophy professor at Northeastern University who focuses on the ethics of emerging technologies.

“There are massive incentives to share new datasets that offer a different perspective on people’s lives,” Basl says. “And this is a population for which they might not have a ton of data.”

It’s a balancing act, Basl says: “The more valuable the social outcomes of a project, the more we might be able to be willing to tolerate some of those privacy or social risks that come along.”

Marisa Zapata, the director of Portland State University’s Homelessness Research & Action Collaboration, says she thinks officials should focus on direct investments in housing, rather than data collection.

“Our fundamental issue is not that we don’t have more information about people,” says Zapata. “It’s that we don’t have enough housing.”

But Meieran, the county commissioner, thinks the region can do both, using the insights from Built for Zero data to make strategic housing investments. She envisions Portland following Bakersfield’s lead and setting up systems to put people in housing or find them other resources while they wait. She sees fewer people going hungry and living on riverbanks.

“It would be a very different Portland than right now,” she said. “My fingers and my toes are crossed.”

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Hanna Merzbach is a reporter and producer for Jackson Hole Community Radio in Wyoming. She has written for The Atlantic, High Country News, and Portland Monthly.


Illustration by Chad Hagen.


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