That used to be my understanding, but after a "discussion" with a local Council officer who disagreed... who knows!A licence is required to place any “apparatus “ under any road. Whether by driving or cut and cover. It is arguable that any farmer who owns both sides should not need one as he owns the subsoil of the road too.
However haveing a licence protects his pipe, cable etc. From damage by future roadworks if these should cause damage.
We never questioned the need, for thrustboring our irrigation pipes through as their was both a large watermain and a very big telecoms cable damaging which could have been hugely expensive. The licence specifies and identifies the nature of cables in the vicinity and the depth they should be at. If you make contact where they should not be , that is their fault