Why does my drain keep clogging?

A one-time clog is normal. A drain that clogs again and again is a symptom — and the cause is almost always in the pipe itself, not the bit of gunk you keep clearing. In older Phoenix-area homes, four culprits account for the overwhelming majority of repeat backups.

1. Tree roots at the joints

This is the number-one cause in the valley. Mature mesquite, ficus, olive, and palm roots are drawn to the moisture and nutrients in sewer lines. They find their way in through the tiny gaps at pipe joints — especially in old clay lines — then grow into a dense mat that snags everything passing by. You snake it, the flow returns, the roots keep growing, and a few months later you’re back where you started.

2. Scale and corrosion in cast iron

Homes built through the 1970s often have cast iron drain lines. From the inside, cast iron corrodes and “tuberculates” — it grows rough, crusty mineral deposits that narrow the pipe and catch debris. A 4-inch line can lose much of its real diameter to scale, so it clogs at flows it used to handle easily.

3. Bellies and settling

Arizona’s expansive clay and caliche soils swell when wet and shrink when dry, especially with monsoon cycles and irrigation. Over decades, that movement can create a low spot — a “belly” — where waste and water pool instead of draining. Solids settle in the sag and build into recurring blockages no amount of snaking will cure.

4. Cracks, offsets, and collapsed sections

Shifting soil cracks rigid pipe and pulls joints out of alignment. Orangeburg pipe (a tar-paper product used widely from the 1940s into the early 1980s) literally delaminates and deforms with age. Each defect is a place for flow to snag and for roots to enter.

Why snaking keeps “working” — and keeps failing

A cable snake (or even a basic auger) punches a hole through a blockage and restores flow. It feels like a fix. But it doesn’t remove roots at the source, doesn’t rebuild a corroded pipe wall, and can’t lift a sagging line. So the problem returns on a schedule. If you’ve paid for the same drain twice, you’ve likely already spent more than diagnosing the real cause would cost.

How a camera inspection settles it

A CCTV sewer camera goes down the line and shows you exactly what’s there — roots, scale, a belly, a crack — and a locator marks where it is in your yard, to the foot. You watch the footage with us. From there the fix is matched to the cause: jetting/descaling to clean, CIPP lining to seal cracks and lock out roots, pipe bursting to replace a collapsed or Orangeburg line, or a spot repair for one bad section.