The sun made a welcome return to the skies over Sydney on March 10, but authorities have warned locals not to hit up the beach despite the fine weather. The floodwaters that inundated areas of the city have begun flowing back into Sydney Harbour, turning the water an ugly shade of brown. Contaminants like soil and sewage are expected to linger in the harbour waters for several days, which could allow algal blooms to emerge. Untreated raw sewage also carries viruses and bacteria that can put the swimmers’ health at risk.
Many other popular swimming spots along the East Coast have been similarly impacted by pollution carried by stormwater. It’s usually recommended that swimmers only return to the water three days after the last rainfall to allow the conditions to return to normal. However, given the scale of the floods that have devastated multiple communities in NSW and Queensland, it may remain unsafe to swim for far longer, as inland flood plains continue to empty into waterways and coastal regions.
According to analysis by the NSW government’s Beachwatch program, samples from Pittwater, Sydney Harbour and Botany Bay all showed higher levels of microbes than normal. In addition to the potential diseases, there is also a risk of injury from hidden objects and debris submerged in the water.