Copper has antimicrobial properties.
Did the ancient Romans notice the health benefit or did they have other reasons for chosing copper for their pipes?
Ancient roman pipes were generally manufactured from lead rather than lead. Lead was abundant as it is a byproduct of silver smelting and it is very easy to work with. Pipes were made by pounding sheet metal around a rod and soldering the seam. This has lead some to speculate that lead poisoning was partially responsible for the fall of the empire, but this claim is disputed.