The short version
- Materials differ: clay, cast iron, galvanized steel, fiber, PVC and polyethylene
- Age, soil and roots all matter
- Leaks and slow flow are common early signs
- A camera inspection shows what is actually happening
What is in the ground
Older homes may have clay or cast iron sewer lines, galvanized steel water lines and fiber conduit pipe. Newer construction usually has PVC for sewer, polyethylene or copper for water and plastic conduit for wiring.
Each material fails in its own way.
How lines fail
Clay cracks and opens at joints, which lets roots in. Cast iron rusts from the inside and the outside. Galvanized steel corrodes and clogs with scale. Fiber pipe softens and deforms. Plastic can crack from rock contact or be crushed by poor backfill.
Movement of soil and heavy loads add stress to every material.
Warning signs
Slow drains, gurgling, odors, wet or sunken ground, lower water pressure, discolored water and sudden jumps in the water bill can all mean a buried line is struggling.
Not every sign is a buried problem, so inspection comes before digging.
What to do
Start with a camera inspection for sewers and a leak check for water lines. The results show whether a repair, a lining or a replacement fits, and how much to dig.
Acting early usually costs less than waiting for a failure at a bad time.
General information, not engineering, legal or safety advice. Rules and requirements vary by utility, city and county.
