[Animats]

That's tight. Here's a document from Network Rail on the practical problems of trying to increase the loading gauge in the UK so containers can fit on electrified lines.[1] That's just to make room for single height containers. In the UK, the catenary clearance is sometimes reduced to get under historic bridges, but that requires slowing trains way down. Sometimes the rail bed is lowered, but that creates drainage problems. Raising historic masonry bridges is even harder. This document has good pictures of all the problems.

[1] https://www.bathnes.gov.uk/sites/default/files/sitedocuments...