Speed cameras will now operate in school zones year-round, from 6 a.m. to 10 p.m. every weekday.
A state law was signed by Governor Andrew Cuomo in May that allows the city to use speed cameras in 750 school zones. But there are plans to extend it even further, to 2,000 cameras, by 2021.
The increase comes after the city was previously allowed to use the cameras in only 140 school zones. The formal announcement of the expanded program was made Thursday morning near P.S. 28 along East Tremont Avenue in the Mount Hope section of the Bronx.
"This is a major step toward our goal of achieving Vision Zero," de Blasio said. "Speed cameras are an invaluable tool that help us save the lives of countless children every year. We're sending a message to all our motorists: drive at a safe speed or pay the price."
WATCH: NYC speed camera program expansion announced in the Bronx
City officials say East Tremont Avenue is a Vision Zero Priority Corridor, which ranks in the top 10 percent of Bronx corridors for number of people killed or severely injured.
Critics of the program, however, say it's just an attempt by the city to raise money.
When cameras catch drivers going 10 miles over the speed limit, they will receive a $50 fine in the mail.
Some worry the program is setting up speed traps with no warning to drivers.
"We have a default speed limit in New York City, and then specific posted speed limits," de Blasio said. "If you don't see a sign, it's supposed to be 25 miles an hour. If there is a sign, the sign governs it. So you don't need a separate sign to tell you there's a speed camera. If you're following the law, you'll be fine."
Lawmakers say the cameras are to help keep pedestrians and students safe.
For more information about the Vision Zero initiative, visit NYC.gov/VisionZero.
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