NEW YORK – New York Mayor Bill de Blasio could soon ink an unprecedented nine-year collective bargaining agreement with the United Federation of Teachers, just months after the city’s teachers union helped elect him to office.

The New York Post reports de Blasio wants to negotiate a retroactive nine-year contract with the UFT that would run from 2009 through 2018, and would push the next round of union negotiations back until after the 2017 elections.

The teachers union, as well as the New York State Nurses Association – which have been without a contract since 2010 – are reportedly looking for substantial raises that are expected to run into the billions, the Post reports.

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Members of the teachers union have not had a significant overall raise lately, although most have almost certainly collected their automatic, annual step raises.

“The nurses’ and teachers’ unions missed out on two years of consecutive raises – of 4 percent each – that nearly every other union got under the Bloomberg administration,” according to the Post. “UFT President Michael Mulgrew has said he expects retroactive raises beyond the pattern established for those two years. That alone would cost the city $3.2 billion.”

The city’s Independent Budget Office reports retroactive raises for all city unions with open contracts could run up to $7 billion, according to the news site.

Apparently, de Blasio thinks he’ll make up some of the money through union concessions on health care costs for city employees, according to the Post’s sources.

“I said we have to find cost savings and that we can’t get to where we need to go without cost savings,” de Blasio said of ongoing contract talks.

But it will take much more than talk about cost savings and heath insurance concessions to put the city back on right financial track. New York City is expected to run into a budget deficit by 2016, before factoring in any potential raises, the news site reports.

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And that deficit could be significantly enlarged by a nine-year deal that would chain the city to expensive labor costs for the next few years. There’s no telling how the economy will perform in that time, so there’s no telling how much the city will be able to responsibly spend on union labor in public schools.

The mayor would do better by negotiate a new teachers union contract that deals exclusively with the future (but only a year or two at a time) and forgets the past. The teachers didn’t get a general raise for a few years. To try to give that to them now, on top of future raises, would be a financial hardship that the city can’t afford.

Righting the city’s financial ship and improving education will take leaders who are not beholden to union bosses, and are willing to put the needs of students and taxpayers ahead of their own political ambitions.

That certainly does not describe Bill de Blasio.