Sabrina and Alana love their harbour pool. They just want cleaner water

For friends Sabrina Santos and Alana Ramshaw, Dawn Fraser Baths in Balmain is a haven on hot days.

“It’s just kind of a nice spot. Relaxed vibes, sun, nice little tuckshop,” said Ramshaw, 23.

“It’s a big part of the community,” said Santos, 28. “It’s been really important to preserve this space, and I have seen a lot of support for it over the years, myself included.”

Ruby with friends Sabrina Santos and Alana Ramshaw at Dawn Fraser Baths.Credit: Steven Siewert

Results of water testing commissioned by The Sydney Morning Herald revealed levels of Enterococci were 10 times the safe level at the baths on January 6, a hot and busy day similar to Monday. This bacteria can cause gastrointestinal illness and is an indicator of faecal contamination.

This contrasts with regular testing by the state government’s Beachwatch scheme, which gives Dawn Fraser Baths a “good” rating based on all results over a year. The prediction for the public holiday Monday, based on the past and forecast weather, was for clean water.

Ramshaw and Santos did not know about any pollution concerns until after they swam, and were sitting relaxing under the balcony with a feast of Twisties and fizzy drinks. Neither regretted the swim, but they would like more focus on ensuring clean water.

Swimmers enjoy Dawn Fraser Baths on a hot public holiday afternoon.Credit: Steven Siewert

“It’s a harbour pool – you’re bound to be exposed to pollution anyway, so I wasn’t too concerned,” Santos said.

“For places that are not on the coastline, it’s really important for people to have access to a swimming spot, especially when it gets hot in summer. There should be more of a concerted effort to keep the pollution at bay.”

Associate Professor Ian Wright, a water expert at Western Sydney University, said Balmain was downstream from a lot of urban development, including the Parramatta CBD and highrise along the river, and the water would be affected by sewage overflow and stormwater run-off including dog poo.

However, that was mitigated by the fact the heritage-listed harbour baths were close to the mouth of the harbour and cleansed by tides twice a day.

“Dawn Fraser is one of the most beautiful pools around and it does get good tidal exchange,” Wright said. “It is saltwater and it’s predictable that after a long period of dry weather and therefore very little runoff, plus that twice-a-day tidal exchange, it’s really good for swimming.

The state government’s Beachwatch program tests ocean, harbour and river swimming sites weekly in summer and issues a twice-daily prediction for the likelihood of pollution based on forecast rainfall.

The Herald collected samples for water testing on November 22 and January 6 and the lab analysis was done by PhD candidate Katherine Warwick. In line with advice not to swim in the harbour for three days after rain, the samples were taken after several days of good weather.

Wright said sites further upstream in the Parramatta and Lane Cove rivers, the main tributaries of Sydney Harbour, would take longer to recover from faecal contamination without the benefit of the tides.

“Basically, you could do a dotted line from the Heads all the way up to Parramatta, and it’ll just get darker and darker, meaning it takes longer to recover and it’s more likely to have faecal contamination,” Wright said.

Wright warned that the new swimming site at Putney “is always going to be a problem” because it’s highly susceptible to fecal contamination, but then it’s going to take a while for that tidal exchange to dilute.

Wright said Lane Cove River was also dirty from urban run-off despite flowing through national park.

“The national park is just within one to two kilometres of the water and right around Lane Cove – all of the ridges are developed,” Wright said. “There’s also a weir so once it gets contaminated, it basically goes brown and stays brown for a couple of weeks. I wouldn’t swim in there for anything.”

Inner West Mayor Darcy Byrne said he would seek an explanation from the NSW government and consider ramping up the testing regime.

“If we need to do testing more frequently to give the public the confidence that it can always swim here safely, that’s what should happen,” Byrne said.

Margaret Gallagher, 71, recalls swimming as a teenager with her friends every summer at Woolwich Baths, or as they called it, Mooney’s Mudhole.

Margaret Gallagher, 71, said she picks up “meticulously” after her five-year-old shar pei dog, Shadow.Credit: Steven Siewert

The 71-year-old inner west resident said people have always known that the harbour and rivers had varying water quality, especially after rain, when the Lane Cove River would turn brown.

Gallagher lives close to Dawn Fraser Baths, where she swims about four times a week usually after consulting the Beachwatch website. It has never made her sick.

“It’s got a decent reputation,” Gallagher said. “They have a lot of water polo here. When the tides out, there’s a little beach there for the kids. You never feel crowded, it’s just open and spacious.”

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