A plumber crouched beside a white sink using a handheld inspection camera, checking the drain while viewing the live feed on a smartphone in a tiled bathroom.

Signs Your Drain is Blocked: What to Look For

May 10, 20250

A blocked drain rarely happens out of nowhere. In most cases, your plumbing system gives off several warning signs before a full blockage occurs. Knowing what to look for, and acting early, can save you from water damage, unpleasant odours, and costly emergency repairs. In this guide, SE Plumbing outlines the most common signs that your drain is blocked and what to do when you notice them.

1. Slow Drainage

If water is taking longer than usual to drain from your sink, shower, or bath, that’s one of the earliest signs of a clog forming.

  • Slow drainage is often caused by soap, hair, or grease buildup
  • The issue typically worsens over time if left unresolved
  • May affect one fixture or multiple areas depending on the blockage location

Our Blocked Drains service can help restore full flow fast.

2. Gurgling Noises

A blocked or partially blocked drain often creates gurgling sounds after water is flushed or drained.

  • Caused by trapped air or pressure in the pipe
  • Common in toilets, sinks, and showers
  • Gurgling can also be heard in nearby fixtures due to shared plumbing lines

If you hear unusual sounds, don’t ignore them—it could be the start of a serious issue. Contact our Emergency Plumbing team for same-day support.

3. Foul Smells Coming from Drains

A bad smell coming from your sink, floor waste, or shower drain is a clear sign of trapped waste or stagnant water.

  • Often due to decaying food, hair, or grease inside the pipes
  • May also indicate a deeper sewer line blockage
  • The smell may worsen after rain or during hot weather

Book a drain clean or inspection through our Contact page before the smell spreads.

4. Water Backing Up into Fixtures

If water comes up from one fixture when you use another, your drainage system is under stress.

  • For example, flushing the toilet may cause water to rise in the shower
  • Indicates a shared pipe is blocked and unable to handle pressure
  • In serious cases, wastewater may overflow onto floors or into other rooms

For urgent support, visit our Emergency Plumbing page and request a priority call-out.

5. Overflowing Outdoor Grates or Pits

Stormwater and sewer drains in your yard or driveway can overflow when a blockage is present.

  • Water may bubble up or pool around external access points
  • Especially common after rain, during heavy water use, or in older homes
  • May also be accompanied by strong sewage smells

Learn more about how we diagnose outdoor drainage issues with our Leak Detection and Prevention service.

6. Toilet Won’t Flush Properly

If your toilet is slow to empty, fills too high, or requires multiple flushes, the pipe may be partially blocked.

  • Waste may remain after flushing or rise instead of draining
  • If multiple toilets are affected, the blockage may be in the main sewer line
  • Bubbling sounds or smells from nearby drains may also occur

We offer fast-response sewer clearing across Sutherland Shire via our Blocked Drains service.

7. Unexplained Puddles or Water Damage

Water pooling near skirting boards, under sinks, or outside drains may be due to a hidden blockage.

  • Leaks may occur when water pressure increases behind the clog
  • Over time, this causes timber damage, mould, and structural issues
  • You may also notice increased water bills

Early detection is key. Our Leak Detection specialists can pinpoint the source quickly and non-invasively.

8. Frequent Clogs in the Same Fixture

If the same sink, shower, or toilet keeps blocking—even after being cleared—it may indicate a bigger issue.

  • Recurring clogs often signal misaligned pipes, root intrusion, or partial collapse
  • Temporary fixes won’t solve the underlying problem
  • A drain camera inspection may be required to determine the true cause

Book a diagnostic visit via our Contact form and let us investigate it properly.

What to Do If You Notice These Signs

Don’t wait for a full blockage to cause flooding or damage. If you notice any of the warning signs above:

  • Stop using the affected fixture
  • Avoid flushing or running water in connected areas
  • Contact a licensed plumber as soon as possible
  • Don’t use chemical drain cleaners—they can worsen the problem or damage pipes

SE Plumbing offers honest advice, fast solutions, and fair pricing on all blocked drain issues.

Protect Your Drains with SE Plumbing — Sutherland Shire’s Blockage Experts

Recognising the signs of a blocked drain early can save you time, money, and stress. Whether it’s a gurgling pipe, a smelly shower, or water backing up into your laundry, SE Plumbing has the experience and tools to diagnose and fix the issue properly. We service homes and businesses across Sutherland Shire and surrounding suburbs, 7 days a week.

Call 0414 651 351 or book online now to stop the blockage before it causes bigger problems.