What to Do When Your Drain Blocks at Night (And Who to Call in Dorset)

It's 11pm. You flush the toilet and the water starts rising instead of draining. Or you notice a foul smell coming from the kitchen sink. Or worse — your garden is flooding from a backed-up drain.

A drainage emergency at night is one of those situations that catches homeowners completely off guard. But knowing what to do in the first few minutes can make a real difference — both to the damage caused and to how quickly you get it resolved.

Step 1: Don't panic — but don't ignore it either

A blocked drain won't fix itself. Left overnight, a partial blockage can become a complete one, and a slow leak can turn into a flooded floor. The sooner you act, the better.

If you're seeing sewage backing up, water rising in multiple fixtures at once, or flooding in your garden, treat it as an emergency and call a drainage engineer straight away.

Step 2: Stop using water in the affected area

If one drain is blocked, avoid using any fixtures connected to it — sinks, toilets, showers, or washing machines. Using them will push more water into an already blocked system and make things worse.

If you're not sure which drains are connected, it's safest to stop using all water in the house until help arrives.

Step 3: Check if it's a simple surface blockage

Sometimes a blocked drain is caused by a build-up of debris at the surface — leaves, hair, or food waste. If you can safely see the drain cover and there's no sewage involved, you can try removing the cover and clearing any visible blockage by hand (wear gloves).

But if the blockage is deeper in the pipe, or if you're dealing with sewage, don't attempt to clear it yourself. You risk making the problem worse or exposing yourself to harmful bacteria.

Step 4: Call a local drainage specialist

This is where having a reliable local number saved in your phone pays off. A professional drainage engineer can diagnose the problem quickly, clear the blockage safely, and check for any underlying issues — like root intrusion or a collapsed pipe — that might cause the same problem again.

In Dorset and Hampshire, Coreflow Drains is available 24 hours a day, 7 days a week. Our local engineers aim to be with you within 60 minutes, and there's no call-out fee — day or night.

What causes drains to block at night?

Grease and fat build-up — cooking fats that solidify in pipes overnight
Tree root intrusion — roots that have grown into older clay pipes
Collapsed or cracked pipes — especially in older properties
Foreign objects — wipes, sanitary products, or children's toys flushed accidentally
Heavy rainfall — overwhelming surface water drainage systems

When to call an emergency drainage engineer

You should call immediately if:

Sewage is backing up into your home
Multiple drains are blocked at the same time
You can smell sewage inside the property
Water is flooding your garden or driveway
You've tried to clear the blockage and it hasn't worked

Don't wait until morning. A drainage emergency that's left overnight can cause significant damage to your property — and the repair bill will be far higher than the cost of a callout.