In an effort to show he's serious on New York's homelessness epidemic, Mayor Bill de Blasio announced he's doubling the number of the city's drop-in centers – from four to eight.

The effort is a result of de Blasio's 90-day review of the city's homeless response efforts following an administration shake-up.

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"Every street homeless person is an individual tragedy, a life gone off course. But sadly they often reject traditional shelters," de Blasio said in a statement. "Drop-in centers are an essential part of the path off the streets, where homeless people can rest, eat, see a case manager, receive medical care and be offered placement into housing."

Those centers are often a bridge gap measure helping vulnerable populations transition into longer term social services. 

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De Blasio said his office estimates the cost of adding onto existing drop-in centers – two in Manhattan, one in Staten Island and one in Brooklyn – to be around $8.5 million annually. He added that, while New York used to operate nine such centers, five were closed between 2008 and 2010 during the tenure of Mayor Michael Bloomberg.

The three new centers will be located in Manhattan, Brooklyn and Queens. The fourth, a currently federally-funded center run by BronxWorks in the Bronx, will now be funded by the city.

In a statement, Manhattan Borough President Gale A. Brewer cheered de Blasio's action.

"Drop-in centers work," Brewer said. "They provide a crucial gateway for the street homeless population to begin connecting with services and shelter and stat on the path to shelter – and eventually permanent housing."