Moreton Bay Regional Council monitors water quality at popular swimming beaches in the region on a weekly basis from October to March (peak swimming season).
Runoff from urban, agricultural and industrial areas (stormwater) can contaminate beaches, particularly after rainfall. This is a potential health risk to people during whole body contact (primary contact) activities, such as swimming, diving and surfing and incidental contact (secondary contact) activities, such as boating, fishing and wading.
What is tested?
The program tests for faecal matter contamination using a microbial indicator called Enterococci. If the Enterococci levels in a waterway are high, this indicates that there may be some form of faecal pollution, potentially from a variety of animal and/or human sources. This translates to a risk of infection.
View the latest test results
Water quality guidelines
The results are measured against The Guidelines for Managing Risks in Recreational Water (NHMRC 2008) [PDF 1.3MB].
The guidelines are designed to be compared against the 95th percentile of the values of a range of samples taken at the location. This means that if 100 samples were collected at a point, then 95 of them should meet the guideline for the water to be considered a low risk for recreation.
We do not have enough data to calculate the 95th percentile yet (guidelines recommend 100 data points), so the weekly ratings are just a snap shot in time of the water quality on that particular day.
What are the health risks?
In polluted waters, swimmers may be exposed to pathogens, which can easily enter the ears, eyes, nose and mouth. The skin is also directly exposed to infectious agents through swimming, playing or working in polluted waters.
This exposure can lead to a variety of health problems including gastroenteritis, urinary tract infections, flu-like illnesses, dermatitis, ear, nose and throat infections, sinusitis and deep tissue or blood infections through open wounds.
The number of pathogens required to cause infections varies widely between micro-organisms and the general health of an individual. Children, the elderly and people with weakened immune systems appear to be at greater risk. Visitors without prior immunity may also be at higher risk than the local population.
General warnings for safe swimming
- Avoid swimming near stormwater drains
- Avoid swimming at beaches during and at least one day after heavy rain in open waterways and beaches, and for at least three days within confined bays and estuaries due to the possibility of pollution from stormwater drains
- Avoid swimming if you see signs of pollution such as discoloured water, oil, scum litter or debris floating on the water or tide line
For further information regarding this program, please contact Council or email firstname.lastname@example.org
Message from the Chief Health Officer of Queensland Health, Dr Jeannette Young, advising of possible health implications associated with using recreational waterways following a flood event:
"Heavy rainfall events can wash microbial and chemical contaminants present in the catchments into waterways, and can overwhelm the capacity of sewage treatment infrastructure causing sewage to discharge directly into waterways," Chief Health Officer Dr Jeannette Young said.
"This typically results in poor water quality in local waterways."
She said exposure to affected waterways, such as beaches, rivers, creeks, ponds, and lakes, can therefore present an elevated health risk in the days or even weeks following a flood event.
The Department of Health advises residents to heed any signage around Southeast Queensland waterways indicating localised risks and to contact their local council for information relating to specific sites.
Dr Young advised that using at risk waterways for recreational activities after heavy rainfall or flooding events could lead to:
- gastrointestinal illness through accidental consumption of water containing disease-causing microorganisms
- respiratory illness from exposure to viruses (e.g. adenovirus), particularly in immunosuppressed people
- ear, eye and skin infections, and more rarely
- infections of the central nervous system