New York completed construction of a new Tappan Zee Bridge, allowing the state to implode the old one this past weekend. But a comparison of the two bridges raises the question: why is bridge construction so expensive?
The original bridge cost $81 million in 1950 dollars. Using a GDP deflator, that’s less than $700 million in today’s dollars. Yet the replacement bridge cost $4 billion, well over five times as much.
First, it should be noted that the bridge is in a stupid location where the Hudson River is three miles wide, while a few miles downstream it is just a mile wide. That significantly increased the cost of both bridges, but the location was selected due to politics: under an interstate compact, all bridge tolls across the Hudson within 25 miles of the Statue of Liberty go to the Port Authority of New York and New Jersey. New York Governor Dewey wanted to keep the tolls to help pay for other roads, so he chose a location just two-tenths of a mile outside the 25-mile radius. Continue reading
