A plumber working on an outdoor drain in a suburban backyard.

How Will You Unblock a Badly Blocked Drain?

May 30, 20250

While minor clogs in sinks and showers can often be cleared with hot water or a plunger, a badly blocked drain is a different story. If your toilet is overflowing, your sink won’t drain at all, or there’s a persistent smell of sewage, you’re dealing with a severe blockage. These require more advanced tools, techniques, and in many cases, the help of a licensed plumber. In this guide, SE Plumbing walks you through what to do when you’re facing a badly blocked drain in your Sutherland Shire home, including step-by-step solutions and how to know when to call in the experts.

What Is Considered a Badly Blocked Drain?

A badly blocked drain is a full or near-total blockage that prevents any water from passing through your pipes. Common signs include:

  • Water backing up into sinks, tubs, or floor drains
  • Toilets that overflow or fail to flush completely
  • Gurgling noises from nearby drains when using taps
  • Foul odours that don’t go away, even after cleaning
  • Multiple drains affected at the same time

These issues may point to a deeper obstruction in your main sewer line or storm water system. For diagnosis, visit our Blocked Drains service page.

Common Causes of Severe Blockages

  • Tree root intrusion in underground sewer lines
  • Years of grease and fat build-up inside kitchen pipes
  • Solid waste, wipes, or sanitary items flushed down toilets
  • Foreign objects lodged deep in the plumbing system
  • Collapsed or damaged pipes due to age or ground movement

If you suspect pipe collapse, head over to our Broken or Damaged Pipes service.

How to Unblock a Badly Blocked Drain

1. Isolate the Problem

Determine whether the blockage is local (e.g. one sink) or affecting multiple fixtures.

  • If multiple drains are blocked, the issue is likely in the main sewer
  • Check external grates or inspection points for signs of overflow

A systemic blockage requires immediate Emergency Plumbing support.

2. Attempt Plunging

If the blockage is isolated to one fixture and hasn’t fully hardened, you may be able to loosen it.

  • Use a heavy-duty flange plunger for toilets or a cup plunger for sinks
  • Create a strong seal and plunge in firm, rhythmic motions
  • Don’t plunge for more than a minute without progress

Avoid repeated plunging if water starts to rise unexpectedly.

3. Use a Manual Drain Snake or Auger

Available from most hardware stores, this tool can help reach deep into your pipes.

  • Feed the auger into the drain slowly
  • Twist to break up or hook the clog
  • Carefully retract and rinse with hot water

For deep or stubborn obstructions, contact SE Plumbing for high-pressure jetting or CCTV camera inspection.

4. Flush with Boiling Water and Dish Soap

This method may help if the blockage is grease-based.

  • Pour half a bottle of dishwashing liquid into the affected drain
  • Follow with boiling water in stages
  • Wait several minutes and check for slow drainage

Note: This method is ineffective for physical blockages like roots or foreign items.

5. Use a Wet/Dry Vacuum (If Available)

If the clog is loose or near the trap, a vacuum may suck it out.

  • Set the vacuum to liquid mode
  • Create a seal around the drain using a cloth
  • Run on high suction for 30 seconds

This works best for sinks and basins. If there’s any sign of sewer smell or outdoor pooling, stop and call us immediately.

Why DIY Methods Often Fail on Severe Blockages

Severe drain issues aren’t just about removal—they’re about locating and resolving the root cause. DIY methods can’t:

  • Cut through solidified grease, soap, or mineral deposits
  • Navigate pipe junctions or bends without causing damage
  • Identify structural damage from roots or collapsed lines
  • Safely remove blockages from stormwater or sewer mains

That’s why our Emergency Plumbing team is equipped with hydro jets and drain cameras to fix the issue quickly and cleanly.

What Happens If You Don’t Fix It

Leaving a badly blocked drain unresolved can lead to:

  • Internal flooding from sewer backflow
  • Mould growth and water damage in floors and walls
  • Pest infestations caused by stagnant water and waste
  • Strong, lingering odours from decomposing materials in pipes

We cover these risks in more detail in our blog on The Dangers of Ignoring a Blocked Drain.

What a Plumber Will Do to Unblock It

At SE Plumbing, our blocked drain specialists use industry-grade equipment to locate and clear even the worst blockages. Our process includes:

  • Locating the clog with a CCTV drain camera
  • Clearing the blockage using high-pressure water jetting
  • Cutting out tree roots with a mechanical rooter
  • Providing a condition report and long-term recommendations
  • Relining or replacing damaged sections if needed

We service all suburbs in the Sutherland Shire, including Engadine, Kirrawee, Miranda, and Cronulla.

Why Choose SE Plumbing for Severe Blockages

We’ve been handling badly blocked drains in Sydney for over 20 years. When DIY fails, we’re ready with tools and experience to solve it for good.

  • Fully licensed and insured professionals
  • 24/7 response for urgent drainage problems
  • Upfront pricing and no call-out surprises
  • Long-term solutions to prevent repeat blockages
  • Locally based in Sutherland Shire for fast dispatch

Call us on 0414 651 351 or book online for same-day service.

Final Thoughts

A badly blocked drain is more than a household annoyance, it’s a plumbing emergency. While there are a few DIY techniques worth trying, major clogs usually require expert equipment and experience. SE Plumbing offers fast, affordable solutions to get your drains flowing again and protect your home from damage. Don’t wait for water to back up, reach out today and let our Sutherland Shire team take care of it.