Blocked drains are usually caused by a build-up of grease, hair, food scraps, foreign objects or tree roots in the pipe. Early signs include slow-draining water, gurgling sounds, bad smells and water backing up. Acting early — and avoiding harsh chemical cleaners — prevents overflows and pipe damage.
What actually causes a blocked drain?
Most blockages build up gradually until water can't get past. The most common culprits we see across Sydney homes are:
- ›Kitchen: fat, oil and grease that cools and hardens inside the pipe, plus food scraps.
- ›Bathroom: hair and soap combining into a stubborn mass in shower and basin drains.
- ›Toilets: wet wipes, sanitary products and too much paper — anything that isn't the 3 P's (pee, poo and paper).
- ›Outside: tree and shrub roots growing into small cracks in underground pipes, chasing the water inside.
- ›Older properties: collapsed, cracked or misaligned pipes that trap everything flowing through.
Early warning signs to watch for
A drain rarely blocks without warning. Catching these signs early usually means a quicker, cheaper fix:
- ›Water draining more slowly than usual from a sink, shower or bath.
- ›Gurgling sounds from sinks, drains or the toilet.
- ›Unpleasant, musty or sewage-like smells near a drain.
- ›Water backing up out of a drain, or the toilet level rising when you run a tap.
- ›More than one fixture affected at once — often a sign the blockage is further down the main line.
Why we don't recommend supermarket drain cleaners
It's tempting to reach for a bottle of chemical drain cleaner, but we'd suggest caution. Harsh cleaners can damage your pipes, are hazardous to handle, and rarely fix the underlying cause — so the blockage keeps coming back.
The safest, longest-lasting fix is to have a licensed plumber find and clear the actual cause — often with a drain camera and professional equipment — rather than mask the symptom.
How to help prevent blocked drains
- ›Never pour fat, oil or grease down the sink — let it cool and bin it.
- ›Use drain strainers in the kitchen and shower to catch scraps and hair.
- ›Only flush the 3 P's — pee, poo and paper. Wet wipes don't break down, even the 'flushable' ones.
- ›Run hot water through kitchen drains regularly to keep them clear.
- ›If you have large trees near your pipes, ask a plumber about a camera inspection to catch root intrusion early.
When to call a plumber
If a blockage keeps returning, affects more than one fixture, or water is backing up, it's time for a professional. Left alone, a blocked drain can lead to overflows, water damage and even pipe failure.
Eagle Plumbing 24/7 clears blocked sinks, showers, toilets, sewer and stormwater drains across Greater Sydney, day and night. We're licensed (498336C), insured, and locate the real cause so it stays fixed. Call 0489 998 221 any time.