The answer to 'difference between sewer line' is that a sewer line and a drain line are two distinct plumbing components that serve different purposes. A sewer line is the main pipe that carries waste and wastewater from your home to the municipal sewer system or a septic tank. In contrast, a drain line is a smaller pipe that collects water and waste from individual fixtures like sinks, showers, and toilets and carries it to the sewer line.
Sewer lines are typically larger in diameter, made of more durable materials like cast iron or PVC, and run deeper underground. They handle a higher volume of waste and water flow compared to drain lines. Drain lines are usually smaller, often 1.5 to 4 inches in diameter, and are made of PVC or other plastic materials. They connect individual fixtures to the main sewer line, transporting wastewater from the home.