Why Does My Drain Keep Blocking After It Has Been Cleared?
Drain blocked again? Learn why clearing may not solve the underlying problem and what an Adelaide plumber should investigate before recommending repairs.
Quick answer
Clearing a drain gets the water moving, but it may not fix the reason it blocked. Tree roots, damaged pipes or a build-up can make the problem return. The next step is finding the cause before choosing another clear-out or a repair.
Clearing a blockage and repairing a pipe are different jobs.
Why does the blockage keep coming back?
Common reasons include:
- Tree roots growing into the pipe through a crack or where two pipes join.
- A broken pipe, or pipes that have shifted out of line.
- A spot in the pipe where waste keeps getting caught.
- Grease, wipes or other items building up inside the drain.
SA Water lists roots and fat, oil and grease as common causes of sewer blockages. Its sewer blockage guide also explains what to do if the problem might be in SA Water's pipes.
These are only possible causes. Two drains can look and sound the same but have different problems.
How do you find the real cause?
The key question is: what caused the blockage, and is it still there?
A drain camera inspection lets the plumber see inside your pipe on a screen. It can show roots, cracks or other damage without digging up your yard.
The camera needs a clear view to work well. Dirty water or a blockage that hasn't been cleared can hide parts of the pipe. So ask what the plumber could see, and what they couldn't.
Ask to see the problem
You don't need to know anything about plumbing to ask for a clear answer. A good plumber will show you the problem and explain it in everyday words.
Questions worth asking
- Where is the problem? Can you show me?
- Is it in one spot, or in more than one place?
- What will clearing it again fix?
- What will it not fix?
- If digging is needed, how will you find the right spot?
Does the drain need clearing or fixing?
If the pipe is in good shape, clearing it and changing what goes down the drain may be enough.
If a cracked pipe keeps letting roots in, it's worth comparing the cost of clearing it again and again with the cost of fixing it once.
Fixes can include replacing the damaged section of pipe, or putting a new lining inside the old pipe (called pipe relining), where that suits. A collapsed pipe usually needs a different fix from a small crack.
Before you agree to any work, ask what it will fix. Compare the mess, the future upkeep and the total cost, not just the price of the next visit.
What if it blocks again?
⚠️ If dirty water is coming back up, stop using that toilet, sink or shower. Keep children and pets away and call for help.
Don't keep flushing to see if it has cleared. If you've used a drain cleaner, tell the plumber which one. Don't add more chemicals.
Need a hand? 👋
When you book, tell us which drains are affected, when they were last cleared and how long they worked before blocking again. If you have old camera footage or a job report, keep it handy.
We help homes across Greater Metropolitan Adelaide with blocked drains. We'll explain what we find in plain English before any work starts.
📅 Book online or 📞 call (08) 7534 5448
Expertise. Clarity. Care.
