Why Is My Drain Backing Up?

Published September 2026 · Pro Plumber Laveen AZ

A drain that backs up is telling you something — and the cause determines whether it's a quick fix or a sign of a bigger issue. Here's what could be happening.

Single Drain Backing Up

When only one drain is affected, the blockage is usually in that fixture's drainpipe:

• Kitchen sink: Grease, food particles, and soap scum accumulate over time, narrowing the pipe until water can't pass.
• Bathroom sink: Hair, soap residue, and toothpaste buildup are the usual culprits.
• Shower/tub: Hair and soap create clogs at the drain cover or in the P-trap.
• Toilet: Excess toilet paper, wipes (even "flushable" ones), or foreign objects block the trapway.

Multiple Drains Backing Up

When two or more drains are slow or backing up simultaneously, the problem is likely in your main sewer line:

• Tree root intrusion: Roots from desert trees like Palo Verde and Mesquite — common in Laveen — seek moisture and can penetrate pipe joints, gradually blocking the line.
• Sewer line collapse: Older clay or Orangeburg pipes can crack or collapse, especially in Laveen's shifting desert soil.
• Main line clog: Years of accumulated buildup in the main sewer line eventually restricts flow enough to cause backups at multiple fixtures.

Warning Signs to Watch For

• Gurgling sounds from drains when other fixtures are running
• Water backing up in the tub when you flush the toilet
• Sewage smell coming from drains
• Wet spots in the yard near the sewer line path

What to Do

For a single slow drain, try a plunger or a drain snake. Avoid chemical drain cleaners — they can damage pipes and rarely clear serious blockages.

For multiple drains backing up, call a professional immediately. This is a main line issue that requires proper equipment like a camera inspection and hydro-jetting.

Call (602) 404-6039 to connect with a drain specialist in Laveen.