The lifespan of a sewer line is dependent on a number of factors, including
what the sewer pipes are made of and various environmental factors like
shifting soil, tree root intrusion, and more. Orangeburg pipes, which
are no longer in use due to their brittleness and short lifespans, last
around 50 years on average. Clay pipes can last anywhere between 50 and
100 years. Cast-iron pipes last around 75 to 100 years on average, and
PVC pipes can last more than 100 years.