Being a motoring and engineering geek, I feel lucky to be so close to the UDOT (Utah Dept. of Transport) "Innovate I-80" project. It's really amazing what they're doing here. They're replacing 7 bridges in 6 weeks along a stretch of the I-80 motorway that bisects Salt Lake City.
Here's the kicker : they're doing it without closing the motorway.
They've built a bridge farm at the intersection of I-80 and 1300 East, and are fabricating all the bridges there. Every weekend, they close down surface streets around I-80, and use massive self-propelled Mammoet low-loaders to drive the pre-assembled bridges to their new destination. At the moment they're doing the westbound lanes and all the normal I-80 traffic has been diverted to the old eastbound bridges. Once the westbound bridges are done, they start over with the eastbound bridges, moving all the traffic on to the new westbound ones.
It truly is an amazing civil engineering project. The bridge farm is a modern marvel all on it's own - I just hope Discovery networks are doing a documentary on this because it deserves to be documented.