A letter writer to the Duluth News Tribune complained a while ago about the need to redo I-35 in Duluth. He said that things like the Golden Gate Bridge in California have lasted a lot longer.
What he ignores is "design life". Engineers plan how long a structure should last and design accordingly. A longer design life will cost more than a shorter design life. Is the money available at the time of building for a really long life? What are the trade-offs between the cost of a long design life and the cost of maintenance?
Lay people like the writer seem to think that all decisions are simple. Ah, if such were life.
