#3... Concrete no longer lasts? No way! Modern concrete lasts way longer than 50 years in fact it is constantly getting harder ... never stops. Unless not mixed right in the first place Check out what the Germans built 70 years ago on coast lines .... not even phased after 75+ years
Roman sewers were built all the way back during the Etruscan reign on the Italian peninsula in 500 BCE. After that, the Romans expanded the sewers. They were primarily used, however, not to expel sewage but to reduce flooding.
#3... Concrete no longer lasts? No way! Modern concrete lasts way longer than 50 years in fact it is constantly getting harder ... never stops. Unless not mixed right in the first place Check out what the Germans built 70 years ago on coast lines .... not even phased after 75+ years