The United States Department of Transportation awarded the O’Hare Modernization Project the largest grant ever for airport construction in the form of a $410 million letter of intent to be used for the construction of two new runways and the extension of a third.

“It’s an enormous amount of money,” said Transportation Secretary Roy LaHood at a press  conference announcing the grant. “But it really is the kind of investment that has to be made at O’Hare.”

The $410 million, combined with $337 million awarded to the project in 2005, adds up to $747 million pledged from the federal government to the project, which Tony Molinaro, Federal Aviation Administration spokesman for the Great Lakes Region, called “incredibly ambitious.”

“That’s the most we’ve ever given to one airport project,” Molinaro said. “It is the biggest airport construction project ever.”

The $747 million from the federal government is just a portion of the funding for the proposed $3.2 billion expansion. The city is still attempting to squeeze some of the needed $2.8 billion from American Airlines and Delta Airlines Inc., which have been resistant to increased fees, and plans to borrow the rest.

The Chronicle’s calls to American and Delta were not returned by press time.

When the grant was announced on April 6, Mayor Richard M. Daley, Gov. Pat Quinn, Sen. Dick Durbin and LaHood all declared  victory.

At the press conference announcing the grant, Quinn said the money for construction  will “foster an environment that creates economic activity, development

and jobs.”

The $410 million will be given out over a 16-year period, from 2011 to 2027. The payout will be “front loaded,” according to Molinaro.

In 2011, the project will receive $40 million, then $30 million per year from 2012 to 2014, then $25 million per year from 2015 to 2022 and $20 million from 2023 to 2027.

In an earlier interview, Daley told The Chronicle that “new runways are the future of Chicago.” Durbin lauded Daley for his “laser focus” on O’Hare.

“Mayor Daley has done an extraordinary job at this airport,” Durbin said at the

press conference.

Molinaro also seemed impressed by the city’s efforts at O’Hare.

“This is not the same as building a new airport,” Molinaro said. “They’re completely changing the airport while the airport is still operating.”

According to the mayor’s press office, the O’Hare Modernization Project has created more than 12,000 construction jobs and around 550 design jobs. The project plans for the construction of two new runways, an extension of another and a new traffic control tower.

The total $15 billion expansion also includes the construction of a new terminal, which the Daley administration wants airlines to help fund.

LaHood called the grant a “very good use of the taxpayers money,” while Quinn said he was glad to see Peoria’s LaHood return to the state because “whenever he comes to Illinois he bears many important gifts.”

LaHood said the money given to the project was part of President Barack Obama’s dedication to job creation.

“I’m delighted … to be a part of an administration that cares so much about putting people to work,” LaHood said.