Aviation Commissioner Ginger Evans and Mayor Rahm Emanuel insist the new runway with "balance out" flights and grant relief to areas hardest hit by O'Hare Airport noise. View Full Caption DNAinfo/Ted Cox

O'HARE — With a roar and a rumble Thursday afternoon, bulldozers began building the sixth and final east-west runway at O'Hare Airport, burying efforts by residents to halt the expansion that has blanketed the Northwest Side with jet noise.

As Mayor Rahm Emanuel broke ground on the $1.3 billion project, he promised it would both fuel the growth of the airport and help Chicago's economy while reducing the racket that many Northwest Side residents say has made it impossible to enjoy their yard or get a good night's sleep.

Heather Cherone chats about the latest major change to O'Hare.

"With this runway, we are taking the next step in strengthening O'Hare's role as the economic driver of the city for decades to come," Emanuel said. "The runway will bring benefits to travelers and residents, and ensures that O'Hare is not just the busiest airport in the world, but also the best airport in the world."

Mayor Rahm Emanuel plots to cast dirt in the direction of reporters at the O'Hare Airport runway groundbreaking. View Full Caption DNAinfo/Ted Cox

Once the 11,245-foot-long, 200-foot-wide $648.5 million runway officially known as 9C/27C opens in 2020, it will accommodate planes that now take off and land on runways on the south side of the airfield, "balancing noise exposure to communities east and west of O'Hare," said Aviation Commissioner Ginger Evans.

Northwest Side residents, as well as those who live in the western suburbs, will "truly experience noise relief" when the new runway opens, Evans said. It will be the second-longest at the airport.

"Without that runway, too much of the brunt will be borne by one area of the city," Emanuel added.

Yet the construction of the final east-west runway as called for by the O'Hare Modernization Program will mean the closure of the diagonal runway on the west side of the airport in 2019. A diagonal runway on the east side of the airport closed a year ago.

An effort by Ald. Anthony Napolitano (41st) to give the City Council veto power over the expansion failed in March.

Members of the Fair Allocation in Runways Coalition have long contended that reopening the diagonal runways are the last, best chance to reduce the roar of jets over the Northwest Side. Yet city officials contend the runways — built in the 1950s — are "fatally flawed" and pose a safety threat to airline passengers throughout the city, officials said.

Despite those concerns, the diagonal runway on the west side of the airport is being used in a six-month pilot program to rotate the O'Hare Airport runways used at night to give residents a break from jet noise.

The group said in a statement that it is "irresponsible" for the city to start construction on the final east-west runway without first allowing the test of the rotation plan to be completed and evaluated.

"This groundbreaking sets into motion the end of the current fly-quiet rotation, taking away the only relief in the last three years that provides the hardest-hit residents with a night’s sleep," the group said.

Ald. Nicholas Sposato (38th), who attended the groundbreaking, said he hoped the new runway would mean noise relief for residents of his ward in Portage Park and Dunning.

"If it can relieve some pressure, that would be a big help," Sposato said. "Any little help we can get."

More than 500,000 complaints about jet noise from Chicago were filed the first four months of 2016, according to the O'Hare Noise Compatibility Commission.

Yet Emanuel has steadfastly refused to reconsider his staunch support of the expansion of the airport, saying it must thrive in order for Chicago's economy to grow.

The new runway adds "the equivalent of the capacity of a third airport," or "another Midway," to O'Hare.

"On many levels, this is more than a runway," Emanuel said. "It opens up the future for the City of Chicago."

The deal to build the new runway paved the way for an agreement with American Airlines to build five new gates in Terminal Three along with plans to build two new hotels on the airfield and renovate a third.

In addition, there are plans in the works to expand the international terminal with nine new gates and envisions renovating Terminal Two, which was built 50 years ago.

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