Blocked Drain Warning Signs You Shouldn't Ignore

Slow-draining sinks, baths or showers

Water that drains more slowly than usual is one of the earliest and most common signs of a developing blockage, often caused by a build-up of grease, soap scum, hair or food debris somewhere in the pipe run.

Gurgling sounds from drains or toilets

A gurgling noise, particularly after flushing a toilet or running water elsewhere in the house, suggests trapped air caused by a partial blockage further down the drainage system. It's often one of the clearest early warnings before a full blockage develops.

Unpleasant smells from drains

• A persistent bad smell from a plughole often means organic material is trapped and decomposing in the pipe
• Smells from an outside gully can indicate a blockage or a damaged drain further along the run
• Sewage-like smells indoors should be treated as a priority, particularly if combined with slow drainage

Water pooling in the garden or around drain covers

Standing water around an external drain cover, particularly after rain, usually points to a blockage or a damaged section of pipe underground. This is worth investigating before it leads to water finding its way somewhere it shouldn't, such as against the foundations of the property.

Recurring blockages at the same point

If the same sink, toilet or drain blocks repeatedly despite clearing it, there's likely a structural cause, such as root ingress, a collapsed section of pipe, or a persistent grease build-up at a particular point. A CCTV drain survey can identify the exact cause and location without needing to dig up the garden speculatively.

What you can safely try first

• Clear visible debris from an accessible sink trap by hand once the water supply is off
• Use a plunger on a slow-draining sink, bath or toilet before reaching for chemical cleaners
• Check external gullies for leaves or debris sitting on top of the grate
• Avoid pouring fat, oil or grease down sinks, letting it cool and harden elsewhere in the pipe instead

When to book a CCTV survey rather than keep clearing it yourself

If a blockage keeps returning despite repeated clearing, or if it's affecting an external drain, gully or chamber rather than a single internal fitting, it's more efficient to book a CCTV survey than to keep treating the symptom. The survey fee covers the first hour, and the footage gives a clear, evidenced answer about what's actually happening underground, whether that's a cracked pipe, a collapsed section, or roots working their way into an old clay joint.

Why chemical drain cleaners aren't always the answer

Shop-bought chemical drain cleaners can shift a minor grease blockage, but used repeatedly they can damage older pipework, particularly older plastic or metal pipes, and they won't touch a structural problem like root ingress or a collapsed pipe. If a blockage doesn't clear after one attempt, it's better to have it investigated properly than to keep pouring in stronger chemicals.