The Minnesota Department of Transportation used a giant automated machine called a Self-Propelled Modular Transporter to move a finished bridge into position over the weekend, and reduced the overall road closure time by two months.

A first for MnDOT, the move took place Aug. 18 over Interstate 35E in St. Paul at the Maryland Avenue Bridge site, where crews have been working all summer long building the bridge deck and structure on the west side of the roadway.

The two 105-foot spans that were built about 1,000 feet south of the crossing. The SPMT, with 352 wheels, took about two hours to move each span into place. Traffic was diverted beginning a few hours earlier.

Saturday's event was a pilot demonstration of SPMT technology that has cut the duration of highway construction-related road closures in Utah and Arizona nearly in half. As a result, MnDOT shaved about two months from road closures in St. Paul.

"With traditional construction methods, the Maryland Bridge would have been closed for twice as long, nearly four months," said MnDOT Commissioner Tom Sorel. "Instead, the closure will be reduced to about 60 days."

Crews have additional work to finish before the bridge is open to traffic in mid-September.

Watch a time-lapse video compressing the 12-hour process into just over a minute:

More information about the I-35E Maryland Avenue Bridge project is available at www.dot.state.mn.us/metro/projects/35estpaul/maryland.html.

Over the next three years, the three corridor projects on I-35E north of St. Paul will change the entrance to St. Paul from the north. In addition to replacing the Maryland Avenue Bridge, the Cayuga Bridge Project, as it's called, will reconstruct I-35E from University Avenue to Maryland Avenue, including replacement of the Cayuga Bridge, the Pennsylvania Avenue Bridge and the railroad bridges along I-35E.

The partial interchange at Pennsylvania Avenue will be replaced by a full interchange at Cayuga Street. The new I-35E roadway will have an auxiliary lane in each direction for added capacity in addition to extra room in the center to accommodate a proposed MnPASS lane. The project will be constructed between 2013 and 2015, with impacts to I-35E traffic in 2014 and 2015.

The I-35E MnPASS project proposes to reconstruct I-35E from Maryland Avenue to Little Canada Road, adding a MnPASS lane to the existing three lanes of traffic. The project will replace the Arlington, Wheelock and Larpenteur Bridges spanning I-35E and replace I-35E bridges spanning Roselawn Avenue, County Road B and Highway 36. This project is expected to be constructed between 2013 and 2015, with impacts to I-35E in 2014 and 2015.