The Baird government plans to change the Public Health Act to make clear the new splash parks and interactive water fountains are included in the definition of a public swimming pool.

While a number of councils have scrambled over winter to work with NSW Health to meet the swimming pool standard in time for summer, one of the most popular water splash parks at Darling Harbour, run by the state government agency Property NSW, insists it doesn't need to.

Property NSW has also refused to answer questions on whether three new interactive water fountains that will open to the public at Darling Harbour in the next fortnight also meet the swimming pool safety standard.

In March, West Australian Premier Colin Barnett apologised to the family of five-year-old Chelsea Fawcett, who developed an eye infection that left her partially blind after playing in a water park at Elizabeth Quay, which was opened by the state government in January.

The Elizabeth Quay water park had closed twice in February after bacteria was detected in pipes amid hot weather. Law firm Slater and Gordon, which is representing the Fawcett family, said this week its "investigations are continuing" as the family considers whether it will sue the West Australian government.

NSW Health's recommendation to include water parks as swimming pools will be included in draft legislation in 2017, says Health Minister Jillian Skinner.

Dr Jeremy McAnulty, NSW Health director of health protection, said: "This recommendation was made because water splash parks and interactive fountains have become increasingly popular in recent years. Anecdotal local reports about these venues, as well as published international reports of diarrhoeal outbreaks, indicate splash park water can be contaminated by users or animals. Concerns about Elizabeth Quay were not the specific prompt."

NSW Health found water in splash parks can "rinse contaminants" from children, including faecal material and bacteria, into the water holding tank, which can then be sprayed from the tank onto other users and potentially swallowed.

Dr McAnulty said treatment of the water can "help reduce the health risk" associated with splash parks.

The City of Parramatta Council has worked closely with NSW Health to recently upgrade two splash parks, the James Ruse Water Playground and the Philip Ruddock Water Playground at Dundas Park, to comply with the new requirements.

"Changes to infrastructure included modifying water disinfection equipment, installing water quality monitoring sensors that continually log water quality data and automatically shut down the facility if water quality parameters are breached," said a council spokeswoman.

She said the advice from NSW Health was "invaluable in helping council to ensure that public safety is maintained at these very popular facilities as we head into another hot summer".

The City of Sydney, which runs the splash park at Pyrmont's Pirrama Park, said it already treats it as a swimming pool.

"Interactive water features are monitored and treated with chemicals daily to maintain pH levels and prevent the spread of water-borne diseases," a council spokesman said.

But a Property NSW spokesman said the splash park it runs at Darling Quarter isn't considered a swimming pool.

"There is a distinction between the water play park at Darling Quarter and public swimming pools which are subject to specific regulatory guidelines," he said.

The grounds at Darling Quarter are irrigated with harvested rainwater and recycled sewage.

The spokesman said the water play park was completely independent and used Sydney Water mains water, was filtrated and chemically treated by an automated dosing system, and was tested twice a day by an external contractor.

One parent, Lara, who was playing with her two-year-old son at Darling Quarter's water park on Saturday, said she preferred it to swimming pools, which were too cold.

"There's sensory opportunities for him. So he'll have the fountains that'll go up and down, and all these other sensory things," she says.

"The only thing that I don't like about this is there's not really much of a standard of what you're supposed to wear in there. So you see some kids with nappies. Some kids will go in naked ... Last time we came we saw a father strip his child naked and wash her off in here, and that sort of grossed me out."

Other parents had thought the child was "weeing in the water", she said.

"My son has the high standard swim nappy on, that all the public and private pools require. But no nappies will stop wee getting into [the pool]. It will stop everything else getting in."

Leanne Grant was at the park with children Alice, 3, and Emily, 10. "I think it's pretty clean usually. Sometimes you see some gross things going on … kids in nappies sitting over a fountain," she said.

Cheryl Jackson prefers to take two-year-old Anika to the splash park because she doesn't have to get in the water with her.

"We'll take a shower straight afterwards, especially her hands. I think if you practise basic hygiene like that, it's pretty safe. In the back of my mind I'm conscious of possible diseases floating around, but you can't stop your life," Ms Jackson said.

The Inner West Council says the Steel Park splash park in Marrickville meets public swimming pool guidelines.

The Blaxland Riverside Park within Sydney Olympic Park is also treated as a swimming pool by the Sydney Olympic Park Authority.