94-year old Pittsburgh bridge falls to controlled explosion.
The 94-year-old, 274 foot Greenfield Bridge in Pittsburgh, Pennsylvania, came tumbling down after a scheduled implosion Monday morning.
In total, 1,400 pounds of explosives were used to bring down the bridge, which landed on a bed of 4,000 cubic yards of dirt spread by crews to cushion the impact of falling debris on the highway.
The project will see a new bridge take its place in two years time at a cost of $17.5 million.
