Lot's of infrastructure was built in 1950s/60s/70s. A reminder if we let rot our infrastructure, it's not good at all. (not implying it's the case with Oroville

Lot's of infrastructure was built in 1950s/60s/70s. A reminder if we let rot our infrastructure, it's not good at all. (not implying it's the case with Oroville dam, haven't followed all news articles) Many concrete and steel structures have a limited life-time of 60-100 years (or so). Big infrastructure projects were built with ease back then, compare it too overblown "paper work" nowadays (not speaking about engineering, but bureaucracy). We should really look how asian countries excel at building infrastructure nowadays (they nowadays build multi-level highways and bridges in no time with ease, whereas building a bridge/tunnels in the west takes many years and cost way too much) and look back in history how to maintain infrastructure well over a timeframe of a few centuries. How many 1950s/60s/70s structures (big things like skyscrappers, dams, bridges, tunnels, subways, etc) are a risk, need repair or are beyond repair and need a replacement - is there a map? Is there a documentation about this topic or some interesting research in this field?