How do I know if my drain is blocked?

Signs include water draining slowly, gurgling sounds, unpleasant smells from drains, and water pooling around floor drains or backing up into fixtures.

Can I unblock a drain with boiling water?

Boiling water can help clear grease blockages in kitchen drains but won't clear solid blockages, tree roots, or collapsed pipes. It can also damage PVC pipes.

When should I call a plumber for a blocked drain?

Call a plumber if the blockage doesn't clear with a plunger, if multiple drains are affected, if there are sewage smells, or if water is backing up in unusual places.

Frequently Asked Questions About Blocked Drains

Christopher Unwin
Dec 4, 2025
2 min read

Updated: May 3

Frequently Asked Questions About Blocked Drains in Melbourne

Here are the questions we get asked most often when Melbourne homeowners call us about a blocked drain.

How do I know if I have a blocked drain or a blocked sewer?

If only one fixture is affected — just the shower, or just the kitchen sink — it's a localised drain blockage. If multiple fixtures are affected simultaneously (e.g. flushing the toilet causes the shower to back up, or the laundry floor drain overflows when the washing machine drains), you have a main sewer blockage. Main sewer blockages are more urgent and require immediate professional attention.

Can I use chemical drain cleaners?

Chemical drain cleaners can clear very mild blockages, but they're largely ineffective against the most common causes — tree root intrusion, solid foreign objects, and structural pipe damage. They can also damage older clay and PVC pipes with repeated use, and they pose a safety risk to the plumber if you've used them immediately before calling. High-pressure water jetting by a licensed plumber is safer, more effective, and doesn't damage your pipes.

How much does it cost to clear a blocked drain in Melbourne?

A standard blocked drain cleared with high-pressure jetting typically costs $200–$450 depending on access and severity. If CCTV inspection is required to diagnose a recurring blockage, add $150–$300. ATC Plumbing always provides a firm price before starting work — no surprises on the invoice.

Why does my drain keep blocking in the same place?

Recurring blockages in the same location almost always indicate a structural problem — usually tree root intrusion through a cracked or separated joint. The blockage clears with jetting but roots regrow through the same entry point within weeks to months. A CCTV inspection identifies the structural issue and pipe relining provides a permanent fix by sealing the entry points roots exploit.

How long does pipe relining take?

Most residential pipe relining jobs are completed in a single day. Longer commercial runs or jobs with multiple access points may take two days. Compare this to excavation-based repair which can involve a week or more of work including surface reinstatement. Call ATC Plumbing on 1300 282 758 for same-day blocked drain service and CCTV inspection across Melbourne's south-east.