David Levinson:

There are new systems emerging. The internet and wireless telecommunications are pretty important. Combine these with transport and we can construct an on-call ride-hailing system that has updated the traditional taxis. This may eventually become substantial with Autonomous Vehicles. But this latter element is not a conventional physical infrastructure investment (not much of one, some servers, some software), rather it redeploys existing (and soon new) vehicles in a useful way.
 The new information-enabled systems that ride on-top of the classic physical layers are the products of Electrical Engineers and Computer Scientists, not great Civil Engineering works. We can imagine some things that might become useful. For instance we can think of space civil engineering, things like Space Elevators and Dyson Spheres. But these are not on the near horizon.
 Unless we can find an infrastructure that increases connectivity massively the way the railroad and the interstate did (doubling speeds, e.g.), there is no point in spending resources for that given the increasingly high costs and diminishing returns that civil infrastructure faces. We have enough trouble maintaining what we have with its proven connectivity (or lack thereof), the value of future infrastructure systems is speculative at best.