Hacker News discussing economics is like arguing geopolitics with someone on peyote.
- The new bridge is designed to handle a much larger capacity than the old one, which was built starting in 1952, when there were many fewer commuters from distant suburbs trying to get to the NYC area.
- The new bridge has a bicycle/pedestrian path.
- The new bridge had to be built while the old bridge was still standing. Its construction costs presumably included the demolition of the old bridge and the rerouting of the highway, first from the old bridge to the first completed span of the new bridge (which initially handled traffic in both directions), then to the second span when that was completed.
- The old bridge was designed with a a life-span of only 50 years, so it was built using cheaper materials. 50 years seems like a very short life-span for a bridge. For example, the Brooklyn Bridge, opened in 1883, is now well into its second century of operation (although it has undergone various renovations, it hasn't required demolition).
Reference: https://en.wikipedia.org/wiki/Tappan_Zee_Bridge_(2017%E2%80%...
Although I don't think it's fair to put all the blame on the Fed. The same thing has happened in the UK and many other places.
Only if you’re optimizing for cost, which public infrastructure very obviously isn’t. It’s optimizing for safety.
Would it be an improvement to build my car out of wood rather than steel? It'd certainly make it a LOT cheaper!