Just in time for the start of the school year tomorrow, DOT has announced that it has finished installing speed cameras at the 140 school zone locations allowed by Albany.

“Our message is, to all drivers in New York, at all times and all places, you should be driving at a safe speed,” Transportation Commissioner Polly Trottenberg said this afternoon at a press conference on Fourth Avenue near Astor Place. “These cameras do protect lives. Speeding is the leading cause of fatal crashes.”

Drivers have to be exceeding the speed limit by at least 10 mph to trigger the cameras. Nevertheless, with just 140 permitted camera locations to monitor 6,000 miles of streets, the program is capturing an incredible number of speeders. The cameras have issued more than 940,000 violations since the beginning of last year, including more than 500,000 so far this year.

The $29 million in fines so far this year will probably lead to a few sensational local TV news segments about how the cameras are lightening driver’s wallets. But the fact is that revenue from the cameras, at $50 per ticket, decreases over time. A year ago, each camera issued an average of 192 violations per day. By last month, that number dropped to 69, DOT said, indicating that drivers are slowing down.

While early results are promising, Trottenberg said the city would have to wait a few more years before it had enough crash data to conclusively show how the cameras are reducing fatalities and injuries.

Today’s announcement marks a milestone for the speed camera program. Albany first approved 20 locations in 2013, then cleared an expansion to 140 last year. Now, more than a year later, the city has completed installing that allotment, with 100 fixed camera locations and 40 mobile units.

Daily News reporter Dan Rivoli asked why it has taken so long. “We wanted to make sure we did it right,” Trottenberg said. “In some jurisdictions, when you don’t do it carefully, the voters go at you and you can lose the whole program.”

Trottenberg was alluding to Long Island, where speed cameras became an election-year hot potato. Outraged drivers pressured Nassau County to shut down its program just months after it rolled out, and Suffolk County terminated its program before the cameras were even turned on. While some in New York City, primarily on Staten Island, have bristled at the safety cameras, there has been no gush of rage against them.

Now that the cameras have all been deployed, street safety advocates are taking aim at the restrictions imposed by Albany on how the city can use them. The cameras can only be located on streets that abut schools, within a quarter-mile of the school. That rules out many streets where speeding is a major problem.

“There are locations where the school is on a side street, and up the block is a main thoroughfare where everybody has to cross to get to the school. And because the law says it has to be abutting the school building, we can’t put them there,” said DOT Deputy Commissioner for Traffic Operations Steve Galgano. “Because the building doesn’t abut the roadway, I’m not allowed to put a camera up.”

Albany also only allows cameras to operate up to an hour before and after school events. That keeps the cameras off overnight and on weekends, when three-quarters of NYC traffic fatalities occur, according to the Department of Motor Vehicles [PDF]. They’re also not on at any time during summer recess, which leads to long gaps with no enforcement and causes rates of speeding to rise before the cameras are turned back on for the school year.

Advocates are pushing to expand the program. “There’s over 2,500 schools. We only have 140 cameras,” said Transportation Alternatives Executive Director Paul Steely White. “Every kid in New York City deserves these live-saving devices.”

While Trottenberg wouldn’t reveal what the city will seek from Albany next year to strengthen the speed camera program, she indicated that it would be a priority. “This is something that I’ve talked about and the mayor’s talked about that we need to tackle,” she said.

Legislators at today’s press conference were a bit more aggressive. “Over time we’ll demonstrate the fact that we are saving lives, and it will be very difficult for my colleagues to reject a program that saves lives,” said Assembly Member Deborah Glick. “Anybody who stands in the way is going to have to answer to their constituents.”