The new bridge going up over the Chelsea River is rising fast.
Twin main supports of the new all steel structure have been hoisted into place and screwed onto cement footings on the Chelsea side of the Chelsea Street Bridge.
Another set of twin main supports will be hoisted into place on the East Boston side of the bridge in short order.
The major disruption will occur when the old bridge is set to come down.
This will require a major junk type salvage operation, with the old bridge being cut into pieces with blow torches and then hauled away to junk yards in cross country style trucks.
An added problem is the enormous cement counterweight that allows the bridge to swing open when ships are passing through the river.
Exactly how the cement will be blasted into pieces remains unknown.
In fact, the order of destruction of the old bridge appears to be of more significance and the cause of greater disruption than the construction of the new bridge which is being made easier by the efficiencies engineers have achieved in the type of modern bridge design being used.