OKLAHOMA CITY (AP) Traffic began to flow Jan. 5 on the new Interstate 40 crosstown expressway in Oklahoma City, a roughly $680 million road project that is the most expensive in the state’s history.

A caravan of antique cars and tractor-trailers from Oklahoma-based businesses christened the 4 mi. (6.4 km), 10-lane section of highway south of downtown that connects the three major interstates that run through the state — Interstates 35, 40 and 44.

“This is fantastic news for Oklahoma and for the nation as we complete work on the corridor connecting the east and west coasts,” said Gov. Mary Fallin. “Completing the I-40 crosstown gives our infrastructure a big upgrade and helps to support a positive climate for trade, business growth and job creation.”

Eastbound traffic was diverted onto the new stretch of highway shortly after noon Jan. 5. Westbound traffic continued on the old I-40 bridge about five blocks to the north.

At 2 mi. (3.2 km) long, the old I-40 crosstown is the longest bridge in the state. Built in 1966 to accommodate about 76,000 vehicles each day, it currently carries as many as 125,000 vehicles each day and has been crumbling for years. A crack was discovered in one of its pier beams in 1989, prompting closure of the major thoroughfare for emergency construction.

“Our biggest headache has been the bridge deck,” said David Streb, the Oklahoma Department of Transportation’s director of engineering. “More than half the bridge is patch. The deck is just in shambles.”

The new crosstown is designed to carry 173,000 vehicles each day, ODOT officials said. Construction began on the project in 2005.

Steel beams between 50 and 80 ft. (15 to 24 m) long that were used in the old I-40 bridge will be inspected after they are removed and made available for counties to use in bridge construction, Streb said.

Approximately $570 million has been spent so far on the new crosstown, which opened more than six months ahead of schedule. More than $100 million will be spent tearing down the old I-40 bridge and constructing a new boulevard in its place.

“We’re very fortunate to be able to design a brand-new street to go right through the heart of downtown, and we intend to make the most of it,” said Oklahoma City Mayor Mick Cornett. “We intend to make it the grandest street this generation has ever seen.”

A new convention center and city park — both part of a 10-year construction project approved by Oklahoma City voters in 2009 — will be built along the boulevard.

Cornett also touted the Skydance Pedestrian Bridge over the new crosstown, an iconic structure with two massive steel “wings” on one side designed in the shape of the state bird — the scissortail flycatcher.

“I’ve traveled I-40 as much as anyone, and I think this is going to be the most iconic structure along Interstate 40, coast to coast,” Cornett said. “People are going to remember they were in Oklahoma City when they see that beautiful art.”

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