Mayor de Blasio says many of the city's homeless simply can't afford the cost of living in New York City.
He says the problem for many is economic. The mayor spoke on the topic Tuesday on WYNC radio's "The Brian Lehrer Show."
Calls to 311 about homeless people in need of aid have risen. There were about 13,000 in the last year of the Bloomberg administration and about 20,000 so far this year.
There are about 56,000 homeless people in city shelters, and an estimated 3,000-plus living on the streets. The crisis has grabbed the attention of city leaders, including Police Commissioner Bill Bratton.
"The homeless population has been steadily increasing," he said. "It's not as though we had a big warehouse and locked them up and let them out on the streets. This problem has been growing. It's reached a tipping point."
The mayor said he thinks there is "both a perception and a reality problem."
"Clearly the number of folks is shelters shot up after 2011, and have remained very high," de Blasio said. "They would have gotten a lot higher if not for the efforts of the people in this administration and beyond."
De Blasio says part of the issue is the end of housing subsidies that kept many people off the streets. He says his administration is working to solve the problems through the creation of affordable housing, and offering mental health aid.
It echoes what homeless advocates say, that the true solution is supportive housing: affordable apartments with counseling on site. The catch: it's expensive and requires state support.
"Governor Cuomo and his administration really control those purse strings," said homeless advocate Alyssa Aguilera. "So when we don't have adequate funding to house homeless people, part of that blame is on the governor as well."
De Blasio says "homeless encampments" won't be tolerated and will be dismantled.
On the radio show, Lehrer referenced NBC 4 New York's exclusive interview last week with former mayor Rudy Giuliani, who said of his own approach to the homeless: "You chase 'em and you chase 'em and you chase 'em, and they either get the treatment that they need or you chase 'em out of the city."
De Blasio said in response: "We don't chase human beings who are in crisis. We try and get them the help they need and off the streets."
Meanwhile, the de Blasio administration's top homeless official, Deputy Mayor Liliam Barrios-Pioli, resigned this week in what many see as a shakeup of the city's homeless approach.