By Matthew Baring-Gould, Kingscliff-based drainage plumber. Servicing Tweed Heads for 4 years. 5.0 stars across 173 Google reviews. Licensed NSW 383340C and QLD 15036450. ABN 74 605 392 348.
Called to a Tweed Heads restaurant to investigate a sewer smell near the back toilet. Cleaned out the basin trap (filthy but not the cause). Cut inspection holes in the plaster to see behind (just block wall, no fault). Removed the cast iron cap on the external stack and ran CCTV through the main sewer – line was free-flowing and clean. Found a continuous drip from somewhere above the sewer that did not match any fixture. Possibly the external aircon condensate line but could not confirm. Charged for the camera only, as the actual cause could not be isolated on the day.
What the customer called us for
Restaurant owner called us out because they were getting a sewer smell near the back toilet. Wanted it diagnosed so they could get it fixed before customers noticed.
What we found when we got there
Diagnostic job rather than a straight fix. The basin trap was filthy but not the smell source. The wall was just block (no hidden pipe). The main sewer, accessed via the external stack, was in good free-flowing condition when cameraed. But there was a continuous drip hitting somewhere above the sewer that we could not isolate to any fixture in the restaurant. Ran the basin, ran the toilet, checked every tap. Drip kept going. Possibly the external aircon condensate discharging somewhere unusual, but we could not confirm without opening up more of the building.
Why we did it this way
A sewer smell in a commercial kitchen or restaurant is a brand-damaging problem but it is also one of the hardest things to fix because the source is almost always hidden. The right approach is to rule out the obvious causes systematically: traps, basins, the main sewer line itself, any accessible pipe work. Once those are ruled out you are into detective work. On this job we ruled out every plumbing fixture and still had the drip, which suggests the problem is non-plumbing (likely the aircon condensate) or a hidden pipe we did not get access to. Charging only for the camera is the honest thing when the result is a diagnosis rather than a repair.
What we did on site
- Attended site and narrowed the location of the sewer smell to next to the back toilet.
- Cleaned out the basin trap and ruled it out as the source.
- Cut inspection holes in the plaster to look at the wall cavity (just block, no hidden pipe).
- Removed the cast iron cap on the external stack and ran CCTV through the main sewer.
- Confirmed the sewer line was free-flowing and in good condition.
- Noticed a continuous drip above the sewer line in the CCTV footage.
- Ran each fixture one by one (basin, toilet, every tap) to try to trace the drip.
- Isolated the external aircon as a likely but unconfirmed source.
- Charged for the camera investigation only, documented findings for the owner.
The result
Main sewer verified clean and free-flowing. Obvious causes ruled out. Mystery drip documented for further investigation. Owner has footage and photos to work with.
If you have the same issue
If you run a restaurant or commercial kitchen in Tweed Heads and you get a sewer smell, do not wait for customers to notice. Get a plumber in for a diagnostic early. Even if we cannot find the cause on day one, we rule out the easy stuff and point you at what to investigate next. Sewer smells rarely fix themselves. Call Matty on 0447 188 394 or request a quote.
Customer names and addresses have been withheld. Individual results vary. Drain Masters Plumbing is licensed in NSW (383340C) and QLD (15036450).
Frequently asked
Why would the main sewer be clean but the smell still be there?
Sewer gas smell can come from anywhere a trap has dried out or a vent is incorrectly installed. An unused floor waste can dry out and let gas up. A badly plumbed vent can push gas back into the room. The main sewer itself can be perfectly clean and the smell still comes from a drying trap somewhere else in the building.
What does a continuous drip have to do with a sewer smell?
The drip itself is not the smell, but it tells us something is flowing where it should not be. Often the water is wetting a surface that then starts to smell as organics break down. If the drip is from an aircon condensate line feeding somewhere unintended, the pooled water can grow bacteria that smells sewer-like.
Why charge only for the camera and not the full visit?
The customer called for a fix and we could not deliver one on the day. The camera work produced value (ruled out the main sewer, documented the drip) so we charge for that. The rest of the time was investigation that did not land on a fix, so we wear that. If we have to come back and the investigation finds the cause, that visit gets charged normally.
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