About Risk Classifications for Beach Grades
Disclaimer: The ‘Risk Classification Status Reports’ below indicate provisional bacterial water quality risk classifications for popular recreational water sites. These risk classifications have been assigned, based on the available information at the time of the Department of Health assessment.
The term ‘provisional classification’ implies that, there are some gaps in information. Therefore, a provisional classification is informative in nature, to serve as a guide of the general bacterial water quality conditions at a specific recreational water site. It is not a guarantee or assurance of the actual bacterial water quality conditions at a given site at any given time or day.
Components of the Risk Classification
The risk classification is made up of 2 parts:
- Microbial Assessment Category (MAC): Assessment of long-term bacterial water quality monitoring results and;
- Sanitary Inspection Category (SIC): Sanitary inspection and risk assessment of potential faecal contaminants.
Understanding Risk Classification Icons
Occasionally, the risk assessment to determine the sanitary inspection category (SIC) may overstate the actual risk. This occurs due to gaps in available information e.g. the effect of rainfall upon a particular sampling site.
When there are gaps in available information, the risk assessment process for determining the SIC, will elevate the risk rating to a higher risk level, as a precautionary measure to ensure that public health is protected. This elevated risk rating remains attached to the site, until such time as additional information is obtained to confirm or verify the true risk rating of the site. At this point a final classification can be assigned.
In order to better understand and communicate provisional site classification information, paddle icons have been developed and are now used to represent risk classifications for most of the listed recreational water sites.
There are a couple of different types of paddles, including a single colour paddle and a two-tone colour paddle. The two-tone colour paddle is divided down the middle into 2 sections with a different colour in each section. The left side indicates the MAC and the right side indicates the SIC.
By looking at the left side colour (representing the MAC), a person can know the bacterial water quality classification for a particular site, based upon the last 5 years' worth of bacterial water sample results.
At the same time, the right side (representing the SIC), if it is a different colour to the MAC, indicates that there is missing information to confirm the actual impact of faecal contamination sources at the site. This may indicate that the SIC has been over-estimated, or that in certain situations e.g. following heavy rainfall events, the sampling site has the potential to pose a greater risk to public health.
Provisional Classification – Paddle Colour Descriptions
The ‘single colour icon’ with a ‘P’ symbol in the middle, implies that either or both the MAC and SIC, are at a provisional classification stage but are at the same risk colour level.
Table 1: Provisional classification – Single colour paddle descriptions
| Paddle design |
Summary |
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Good: Based upon incomplete information available to date, bacterial water quality appears to be safe for swimming most of the time. Water quality results to date have been good on most occasions and there are few potential faecal contamination sources identified.
Standard warnings apply e.g. avoid swimming after heavy rainfall (>10mm): for up to 3 days in fresh to estuarine waters, and for 1 day in ocean/marine waters. |
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Fair: Based upon incomplete information available to date, bacterial water quality appears to be variable at this location. Water quality results at times appear to be safe for swimming; however elevated bacterial levels can also make this site unsuitable for swimming.
Elevated bacterial levels are likely due to animal pollutant sources e.g. bird faeces, and from contaminants flushing into the water following rainfall.
Swimming should be avoided during and for several days following heavy rainfall (>10mm) and if the water is discoloured, murky or has visual pollution.
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Poor: Based upon incomplete information available to date, bacterial water quality often appears to be unsatisfactory for swimming.
Elevated bacterial levels occur during and following rainfall events, and/or as a result of stormwater drain inflow, or due to animal pollutant sources e.g. birds. Other factors such as low dilution, tidal movement and wind direction may enable bacteria to survive longer in these waters.
There may be a greater risk of illness if you ingest the water, particularly by the very young, the elderly and those with compromised immunity. Swimming or putting your head under water should be avoided. |
The ‘two-tone paddle colour icon’ relates directly to the MAC and SIC, either or both of which are at the provisional classification stage. The colour on the left represents the MAC and the colour on the right represents the SIC.
Table 2: Provisional classification – Two tone paddle colour descriptions
| Paddle design |
Summary |
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|
MAC: Based upon incomplete information available to date, bacterial water quality appears to be safe for swimming most of the time.
Standard warnings apply: avoid swimming after heavy rainfall (>10mm): for up to 3 days in fresh to estuarine waters, and for 1 day in ocean/marine waters.
SIC: Based upon incomplete information available to date, elevated bacterial levels are likely to be due to animal pollutant sources e.g. bird faeces, and from contaminants flushing into the water following rainfall. |
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MAC: Based upon incomplete information available to date, bacterial water quality appears to be safe for swimming most of the time.
Standard warnings apply: avoid swimming after heavy rainfall (>10mm): for up to 3 days in fresh to estuarine waters, and for 1 day in ocean/marine waters.
SIC: Verification of SIC is required. SIC may over emphasise the actual risk.
Elevated bacterial levels may occur during and following rainfall events, and/or as a result of stormwater drain inflow, or due to animal pollutant sources e.g. birds. Other factors such as low dilution, tidal movement and wind direction may enable bacteria to survive longer in these waters.
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MAC: Based upon incomplete information available to date, bacterial water quality appears to be variable at this location. Water quality results at times appear to be safe for swimming; however elevated bacterial levels can also make this site unsuitable for swimming.
Swimming should be avoided during and for several days following heavy rainfall (>10mm) and if the water is discoloured, murky or has visual pollution.
SIC: Verification of SIC is required, as few potential faecal contamination sources have been identified; but bacterial water quality results to date have been variable.
Elevated bacterial levels are likely from animal pollutant sources (e.g. bird faeces) and contaminants flushing into the water following rainfall. |
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MAC: Based upon incomplete information available to date, bacterial water quality appears to be variable at this location. Water quality results at times appear to be safe for swimming; however elevated bacterial levels can also make this site unsuitable for swimming.
Swimming should be avoided during and for several days following heavy rainfall (>10mm) and if the water is discoloured, murky or has any visual pollution.
SIC: Based upon incomplete information available to date, elevated bacterial levels may occur during and following rainfall events, and/or as a result of stormwater drain inflow, or due to animal pollutant sources e.g. birds. Other factors such as low dilution, tidal movement and wind direction may enable bacteria to survive longer in these waters. |
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MAC: Based upon incomplete information available to date, bacterial water quality appears to be unsatisfactory for swimming.
There may be a greater risk of illness if you ingest the water, particularly by the very young, the elderly and those with compromised immunity.
Avoid swimming or putting your head under water. Permanent warning signs erected at this site stating that swimming is not recommended should be considered.
SIC: Verification of SIC is required, as few potential faecal contamination sources have been identified; but bacterial water quality results to date have generally been unsatisfactory for swimming.
Elevated bacterial levels occur during and following rainfall events, and/or as a result of stormwater drain inflow, or due to animal pollutant sources e.g. birds. Other factors such as low dilution, tidal movement and wind direction may enable bacteria to survive longer in these waters. |
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MAC: Based upon incomplete information available to date, bacterial water quality appears to be unsatisfactory for swimming.
There may be a greater risk of illness if you ingest the water, particularly by the very young, the elderly and those with compromised immunity.
Avoid swimming or putting your head under water. Permanent warning signs erected at this site stating that swimming is not recommended should be considered.
SIC: Based upon incomplete information available to date, elevated bacterial levels appear mostly due to animal pollutant sources, stormwater inflow, and during and after rainfall events due to contaminants flushing into the water. |
Final classification – Paddle Colour Descriptions
A final classification will be displayed as one colour: green, amber or red. This implies that the MAC has been obtained with a minimum of 65 samples over 5 consecutive years, and individual faecal risk factors for the SIC have been substantiated, or alternatively, management initiatives or activities relating to the SIC have been undertaken to address any potential risks that may not have been fully validated.
Table 3: Final classification – Paddle colour descriptions
| Paddle design |
Summary |
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Very Good: Bacterial water quality is considered safe for swimming at all times. Water sampling results are consistently very good, and there are very few or low risk faecal contamination sources at this location.
Good: Bacterial water quality is considered safe for swimming most of the time. Water sampling results are good on most occasions, and there are few or low risk faecal contamination sources at this location.
Standard warnings apply e.g. avoid swimming after heavy rainfall (>10mm): for up to 3 days in fresh to estuarine waters, and for 1 day in ocean/marine waters. |
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Fair: Bacterial water quality is variable at this location. Water quality is at times considered safe for swimming; however elevated bacterial levels can also make this site unsuitable for swimming.
Elevated bacterial levels are mostly due to animal pollutant sources e.g. bird faeces, and from contaminants flushing into the water following rainfall.
Swimming should be avoided during and for several days following heavy rainfall (>10mm) and if the water is discoloured, murky or has any visual pollution. |
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|
Poor: Bacterial water quality is often unsatisfactory for swimming. Elevated bacterial levels occur during and following rainfall events, and/or as a result of stormwater drain inflow, or due to animal pollutant sources e.g. bird faeces.
Other factors such as low dilution, tidal movement and wind direction may enable bacteria to survive longer in these waters.
There may be a greater risk of illness if you ingest the water, particularly by the very young, the elderly and those with compromised immunity. Swimming or putting your head under water should be avoided. Activities such as canoeing, boating and fishing are still suitable.
Very Poor: Bacterial water quality is mostly unsatisfactory. Avoid swimming at this location, as there may be direct discharges of faecal material or other pollution sources.
Permanent warning signs should be erected at this site stating that swimming is not recommended. |
New or proposed sample sites
Table 4: New or proposed sample sites
| Paddle design |
Summary |
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New Sample Site: Insufficient water quality or site information is available to assign a bacterial risk classification. |
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Proposed New Sample Site: This site is currently been considered for future bacterial water quality monitoring |
Last reviewed: 11-01-2021
Produced by
Environmental Health Directorate