Redland City Council officers have warned that major environmental constraints could complicate flood mitigation works at several Redland Bay waterways, with further modelling and investigations likely required before any significant action is taken.
A report to be considered at next week’s council meeting outlines flood-related issues at Weinam Creek, Torquay Creek, and the Pitt Street Wetlands, following a notice of motion last year seeking a schedule for clearing watercourses and debris to reduce flood risks.
Councillors requested the investigation in November 2025 after concerns were raised about flooding impacts on nearby properties and roads.
Weinam Creek concerns near Cliftonville Place
Officers confirmed that properties at 10 and 11 Cliftonville Place, Redland Bay had come close to flooding during recent heavy rain events, with water reported to have entered at least one property.
Photographs and debris lines provided by residents showed flood levels approaching homes, with yards regularly inundated.
However, earlier flood modelling completed in October 2022 found the culverts beneath Moores Road largely control upstream flooding levels.
The downstream section of the creek sits within an Environmental Conservation Area, where flooding during major events can create localised pooling.
Officers warned that simply clearing vegetation from the waterway would likely provide “limited benefit” in reducing flood risk.
Instead, several other factors may be contributing to flooding, including:
• sediment and vegetation build-up restricting water flow
• high tide levels reducing the creek’s ability to drain
• narrowing of the waterway following construction of the Moores Road carpark
• potential blockages at a large culvert beneath Moores Road.
The area is also environmentally sensitive, supporting four nationally recognised threatened ecological communities and habitat for 92 endangered or vulnerable species, including flying foxes and the false water rat.
Council officers say further flood modelling is needed to determine whether homes are at unacceptable risk and what mitigation works could be effective.
However, funding for that modelling is not currently available and will need to be sought through the 2026–27 operating budget.
Any future works could also trigger environmental assessments under the Environment Protection and Biodiversity Conservation Act due to the presence of protected species and habitats.
Torquay Creek: flooding expected but limited impact
At Torquay Creek, near Serpentine Creek Road, officers found that flooding across part of a private property is expected due to an existing drainage easement.
The property at 62–66 Serpentine Creek Road sits higher than the flood-prone drainage area and the dwelling itself has not been affected by flooding.
During heavy rainfall, Serpentine Creek Road can temporarily flood, but residents still have alternative access routes.
Officers said the waterway sits within a sensitive wetland system linked to the Moreton Bay Ramsar site, which supports significant biodiversity including the Wallum Sedge Frog, False Water Rat and flying foxes.
Because no broader flooding issues have been identified and clearing vegetation could harm the ecosystem, officers are recommending no additional works beyond routine waterway management.
Pitt Street wetlands works planned
At the Pitt Street Wetlands, the main concern identified is a bio-retention basin near 19 Salisbury Street that frequently holds water and has become a nuisance for a nearby property owner.
The stormwater treatment basin was constructed about a decade ago but was never formally handed over to council, leaving it without proper maintenance after the developer became insolvent.
Council has since taken ownership of the asset after retaining the developer’s bond.
Officers say vegetation inside the basin and ponding in nearby drainage channels are contributing to the issue.
To improve drainage, council plans to:
• remove vegetation within the basin
• construct a 30-metre concrete open drain near Salisbury Street.
Design work is scheduled for the 2026–27 financial year, with construction expected in 2027–28.
The project has been listed as a high-priority capital works item and is expected to improve water quality and stormwater management without significant environmental impacts.
Environmental approvals may be required
The report warns that works across the three sites could trigger environmental approvals under several state and federal laws, including:
• the Environment Protection and Biodiversity Conservation Act
• the Environmental Protection Act
• the Water Act
• the Fisheries Act.
Council must also comply with planning requirements under its Waterways and Wetlands Overlay and Healthy Waters Code.
Recommendation to councillors
Officers are recommending councillors simply note the findings of the investigation and endorse the proposed approach:
• further modelling for Weinam Creek
• no additional works at Torquay Creek
• drainage improvements at Pitt Street Wetlands.
The matter will be debated at the Redland City Council general meeting on March 18.
