5 Warning Signs Your Drain Is About to Block Completely (and What to Do First)

Introduction

Drains rarely fail without warning. By the time sewage is bubbling up through the shower, the problem has usually been quietly building for weeks. Here are the five signals our team sees over and over again — and what you can safely try yourself before calling a plumber.

The 5 warning signs

### 1. Gurgling sounds when water drains

That ‘glug-glug’ noise is air being forced past a partial blockage. It usually means the obstruction is downstream, often in the main line.

### 2. Multiple fixtures slow at once

If your kitchen sink AND laundry tub are both slow, the issue isn’t local — it’s in the shared line. This is the #1 sign of a main drain problem.

### 3. Bad smells from drains or outside

A rotten-egg or sewage smell near gully traps means waste is sitting where it shouldn’t. Don’t ignore it — it can become a health hazard fast.

### 4. Toilet water rises when you flush

If the bowl fills higher than normal before draining slowly, the sewer line is restricted. Stop using it until inspected.

### 5. Wet patches in the yard or lifting pavers

A collapsed or root-invaded sewer line often shows up as a soggy patch above the run. This is a repair job, not a clearing job.

What to safely try yourself first

• Boiling water + dish soap down a kitchen sink (grease blockages only)
• A proper cup plunger with a wet seal — 20–30 firm strokes
• Removing and cleaning the P-trap under a basin (bucket underneath!)
• Half a cup of bicarb + a cup of vinegar, then hot water (mild blockages)

What NOT to do: Avoid supermarket caustic drain cleaners on older pipes — they can damage seals and PVC, and they make a plumber’s job harder (and your bill higher). Never use them in a toilet.

When to stop and call a plumber

Call us immediately if: more than one fixture is affected, sewage is visible, a toilet is overflowing, or you’ve already tried twice without success. Continuing to plunge a serious blockage can crack seals and turn a $400 job into a $4,000 one.

FAQ

How long can I leave a slow drain?

A single slow fixture can usually wait a few days. Multiple slow fixtures or any sewage smell should be looked at within 24 hours.

Will a CCTV inspection always be needed?

Not always. We recommend it when blockages recur, when tree roots are suspected, or before any relining work.

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Caught one of these signs early? Book a same-day inspection with J.O. Plumbing and avoid the after-hours emergency bill.