Several popular Sydney locations are the latest Australian beaches that swimmers have been warned to avoid in certain weather conditions due to faecal pollution.

Popular Sydney ocean beaches with poor grades included Shelly Beach, Bronte Beach and Coogee Beach, with the problem not just confined to NSW.

The annual State of the Beaches Report gave NSW’s swimming spots grades from “very good” to “very poor” based on water quality samples collected at sites monitored under Beachwatch and Beachwatch partnership programs.

Although 95 per cent of the state’s ocean beaches passed with very good or good grades, several were graded poor, meaning the locations were susceptible to faecal pollution levels that were not always suitable for swimming.

Many of the state’s lakes, lagoons, estuaries (tidal mouths of large rivers) and freshwater swimming locations also received poor or very poor grades.

Warning signs

Swimming at poor-graded beaches is considered generally acceptable during dry weather conditions if there are no signs of pollution, such as discoloured water, odour or debris.

But the report advised swimming should be avoided at ocean beaches during and for up to three days following rainfall.

With the Bureau of Meteorology predicting a wet summer for the state, swimmers are encouraged to check a location’s grade from Beachwatch before diving in.

“NSW beaches and inland swim spots are some of the best in the world,” NSW Minister for Climate Change and the Environment Penny Sharpe said.

“Our beaches almost always have high water quality, but after rain the quality can be impacted.”

The report blamed ocean beaches’ elevated risk of faecal pollution after rainfall on factors, varying between locations, such as:

• Stormwater
• Domestic dog faeces entering waterways
• Overflows of sewage treatment plant discharge
• Failure or leakage of sewer management systems.

National problem

NSW is not the only state or territory battling faeces in its waters.

In 2019, academics from Western Sydney University, the University of Tasmania, and the CSIRO found the bigger the coastal community, the bigger the volume of sewage that could pollute ocean waters, affecting regular and affluent communities alike.

Each state and territory recommends avoiding swimming in natural bodies of water during and directly after rainfall, but take different approaches to informing communities about risks of specific sites.

Western Australia, Victoria and the Australian Capital Territory regularly publish water quality results, South Australia offers alerts for certain beaches, while some Queensland and Tasmanian city councils publish assessments of local waterways.

The Northern Territory put water quality testing of Darwin Harbour and beaches out to tender in 2011 after high levels of dangerous bacteria were detected at popular swimming spots East Point beach and Lake Alexander.

More recent monitoring results are not easily found online.

Other issues

Faecal matter is not the only contaminant NSW beachgoers are facing; thousands of mysterious black balls have washed up on multiple beaches in recent weeks.

Randwick City Council said preliminary tests indicated the balls were a “hydrocarbon-based pollutant, which is consistent with the makeup of tar balls”.

But the NSW Environmental Protection Authority (EPA) said it could not confirm Randwick City Council’s findings, and as of October 17 the origins of the balls remained a mystery.

No further update from the NSW EPA is currently available.