Because that was the best material they had at that time.
Lead water pipes.
Yes and it still widely used even today
That was the best material they had.
At the time of the Roman Empire, the Romans used pipes made of lead, because it is a cheap metal that is easily worked into pipes, and which unlike iron doesn't rust. The Romans didn't worry about lead poisoning. Lead pipes continued to be used even into the mid 20th century, before we became more concerned about the danger of lead poisoning.
It wasn't. Aqueducts were made of stone, engineered to amazingly exact specifications, then polished and smoothed. Lead was actually advised against for the use in aqueducts, for its toxicity, by Vitruvius in De Architectura.
Lead water pipes.
Yes and it still widely used even today
That was the best material they had.
Iron replaced lead in water pipes.
That was the best material they had at that time.
At the time of the Roman Empire, the Romans used pipes made of lead, because it is a cheap metal that is easily worked into pipes, and which unlike iron doesn't rust. The Romans didn't worry about lead poisoning. Lead pipes continued to be used even into the mid 20th century, before we became more concerned about the danger of lead poisoning.
Lead is malleable, corrosion-resistant, and has low melting point, making it suitable for use in water pipes.
Because they had no better materials at that time.
Lead pipes are not considered safe for use in plumbing systems because lead can leach into the water supply, posing health risks such as lead poisoning. It is recommended to replace lead pipes with safer alternatives.
Plastic was not invented during that time period.
The Romans used the first basic pipes, aqueducts, baths and many other innovations in water usage.
Lead was used for water pipes because it is cheaper, more malleable, and more flexible, and can be welded together easily. But it should not be used for water pipes of any kind because of the risk of water contamination. Metals such as copper are more expensive but superior in performance, and modern PVC is much lighter and easier to use for drainage pipes, and for pipes not carrying great pressure.