Old Bridge, New Bridge

They announced last week in church that this road would be closed because they were replacing the bridge.  A new bridge span was being put together in the parking lot, to the right in this photo.  I assumed they would be using cranes to move it into place.  I was wrong.

When we were going into the church just down the block, the old bridge was gone.  When we came out of Mass an hour later, the new span was in place already!  How did they do that?

Well, they had this amazing machine, which is painted red, and is made up of what looks like two trailers fastened together with heavy red pipes.  I counted about 140 tires on both of the trailers together!  The machine drove under the old bridge, jacked it up, and then drove to the parking lot, on the right in the photo, and lowered the old bridge to the gray I-beam supports which is where it rests now.  Then the machine drove under the new bridge, also on the I-beam supports, lifted it slightly and drove it over to install it where the old bridge was!  Man oh man, what a cool operation.  I wish I had gotten to see the whole process.

This is the old bridge, now stored while it awaits being dismanteled.

And this is one of the two trailers still holding the new bridge up, while supports are adjusted.  It is an enormous machine.  72 tires underneath just this one trailer alone!