A strong rotten egg smell has been troubling Redcliffe locals this winter, but it’s not coming from the sewers. Instead, it’s the result of a natural process linked to mangroves growing near the coastline.
Where The Smell Is Coming From
Since May, residents in Redcliffe, Newport, Clontarf, and Scarborough have reported a foul odour, often strongest at night or early morning. While many suspected broken pipes, Unitywater found that about a quarter of cases weren’t linked to sewer faults.
Instead, the smell is often caused by mangroves dropping seeds that decompose and release sulphide gas during the cooler months. This gas, which smells like rotten eggs, becomes more noticeable in winter as cold air traps it close to the ground. Wind and tidal conditions can also spread the smell further, especially near shorelines and stormwater drains.
Investigations And Response
Over the past year, Unitywater received 376 odour-related reports from areas including Moreton Bay, the Sunshine Coast, and Noosa. Each case was investigated to rule out issues with the wastewater network. About 24 per cent of the complaints were linked to natural sources like mangroves, wetlands, or riverbanks.
Unitywater advises residents to consider their surroundings, like proximity to mangroves, recent rain, temperature shifts, and wind direction, before assuming it’s a sewer problem. This helps distinguish natural odours from actual infrastructure faults.
What Residents Can Do
While the smell can be unpleasant, Unitywater warns residents not to take matters into their own hands. Some locals have considered removing nearby mangroves, but doing so without approval is illegal in Queensland.
Mangroves are protected due to their vital role in preventing erosion and supporting wildlife. They help stabilise riverbanks and provide habitat for birds, fish, and bees. Removing them can harm the environment and potentially cause long-term damage to nearby properties.
Living With It—For Now
With no long-term fix in place, community awareness has become the best way to manage the issue for now. Some locals have adapted by closing windows or using filters indoors, while others laugh it off as a quirky sign that winter has arrived.
Unitywater continues to monitor its systems closely to rule out any genuine faults. They’re urging residents to keep reporting strange or lingering smells, just in case. After all, not every stink is just nature doing its thing.
Published 24-July-2025
