"Pranzano lungo l'acqua"
This is oddly translated as "they have dinner along the water": English usage requires 'by' rather than 'along' where the subject is static and at a single point rather than distributed along the waterfront, but this is not accepted.
NB this point has already been made several times in relation to other sentences using 'lungo l'acqua' but either this one is new or it has been overlooked.
You will find in studying a Romance language, especially Italian, that the usage is sometimes very formal and dramatic, and more technically accurate than in English. In Italy you don't "get off" a bus. You "go down". (Scendere) And you don't "get on", you "go up." (Salire). Think as if you are performing in a play when you speak Italian and it will make more sense.