The answer to 'lifespan of sewer line' is that the average lifespan of a sewer line is 50-100 years, depending on the material. Sewer lines made of cast iron or clay can last 50-80 years, while plastic or PVC pipes can last 80-100 years with proper installation and maintenance. However, factors like soil conditions, tree roots, and usage can affect the actual lifespan of a sewer line.
Regular inspection and maintenance, such as hydro-jetting to clear blockages and prevent backups, can help extend the life of a sewer line. If you notice any signs of a problem, like slow drains or sewage backups, it's best to have a professional plumber inspect the line to determine if repairs or replacement are needed.