A new WNYC Data News map of public and private schools shows that two thirds of streets are within a quarter of a mile of schools, with that number climbing to nearly nine of every 10 streets in Manhattan, 82 percent of streets in Brooklyn, and 74 percent in the Bronx.

As Transportation Nation reported last week, state law restricts how much localities can lower speed limits.  But there's a loophole: if streets are within a quarter mile of a school the city can act without state approval to lower limits to 20 mph. 

Because of the the density of New York City and its schools, that's two-thirds of all city streets if public and private schools are mapped. Even in the borough with the lowest school density, Staten Island, four of every 10 miles of streets would be affected. 

Even more streets might be affected than reflected above, however.  WNYC doesn't yet have reliable data on day care center locations -- those areas are also subject to restricted speed limits.

There are nearly 300 traffic fatalities a year.  Several recent high-profile deaths of children have galvanized officials towards action.  Mayor-Elect Bill de Blasio has signed on to a plan to reduce fatalities to zero, though he hasn't commented on how much he would want to limit speeds, or on which streets. 

One of the candidates for Police Commissioner, Bill Bratton, speaks at a forum on transportation policy on Tuesday.  The event is sponsored by NYU's Rudin Center and by Transportation Alternatives, vocal advocates of reduced speed limits and greater traffic enforcement.