With the new school year in session, an analysis of traffic injury numbers by WNYC shows that NYPD and DOT need to step up on enforcement and engineering improvements to prevent motorists from hurting kids.

Year after year, traffic crashes rank as the leading cause of injury-related death for children in NYC. Drawing on state DMV data from 2009 through April 2012, WNYC found that about 1,800 kids between the ages of five and 17 are struck by city motorists every year, an average of almost five each day. Focusing on the hours of 6:30 to 8:30 a.m. and 2:30 to 4:30 p.m. on school days, when school-age children account for one-third of all pedestrian victims, Coulter Jones and Alex Goldmark report that most kids who were hit were crossing with the signal or mid-block. (The vast majority of adults struck by motorists during those hours were crossing with the signal.)

Data show that 7 percent of injuries before and after school involved kids who emerged — or “darted,” in the victim-blaming parlance of motordom — from between parked cars. Under 4 percent of kids were struck while “playing in roadway,” which was known simply as “playing” before streets were ceded to motor vehicles.

WNYC points out that kids can’t detect the presence of oncoming vehicles or gauge speed as well as adults do, and that in the event of a collision the likelihood of a pedestrian’s survival depends on how fast the motorist is driving.

All of this adds up to an argument for protecting children on their way to school through a mix of education and policy, not just telling kids to look both ways [see Safety City]. Parents and crossing guards can look out for children and teach them to follow traffic rules, but enforcement against speeding and redesigning intersections can also have a dramatic impact.

Injuries to kids have dropped 44 percent near 100 or so schools selected to receive federally-funded Safe Routes to School improvements. But there are 1,200 school buildings in the city, WNYC notes, and Safe Routes funds were reduced in the latest federal transportation bill.

“[T]here are hundreds if not thousands of intersections near schools that have been improved … in the last five years,” DOT Commissioner Janette Sadik-Khan told WNYC. “All of our projects take into account seniors and schoolchildren.”

Yesterday, as kids headed back to class, DOT activated NYC’s first 20 speed cameras in city school zones. Conditions imposed by state lawmakers mean the cameras are operable only from one hour before the school day begins to one hour after it ends, and from 30 minutes before to 30 minutes after school activities. A driver can go up to 10 mph over the speed limit without getting a ticket. Violators will be sent warnings for the first few weeks of the program, after which the fine will be $50 for exceeding the speed limit by 11 mph or more in a school zone where kids are present. DOT hopes to make the most of the cameras by moving them around, and Tri-State Transportation Campaign reports that the expected calming effect may extend beyond school zones.

NYPD will evidently continue to allow motorists to speed through neighborhoods and endanger lives at will. Sadik-Khan says Ray Kelly’s department has no plans to change its enforcement methods now that speed cameras are in place.