This weekend it incorporates dance, song, video installations and visual displays via an interactive two kilometre walk along the Georges River in the city's southwest led by culturally diverse local artists.

For Yuhana Nashmi it's about honouring his ancestors' reverence of water through two displays among the more than 330 being exhibited by around 90 contributors in total.

His roots are Mandean - a small Gnostic religious sect hailing from Iraq and Iran that is several thousands years old - and he believes rivers carry a critical cultural current.

"There's no life, if there are no rivers," Mr Nashmi says.

"We are considered gatekeepers or conservationists of water and nature ... it is the main source of life and light which has a divinity to it".

The long-haired, bearded and softly spoken artist is arranging over 200 terracotta clay figurines collated from workshops he held for around a hundred other Mandean artists as well as Bosnians, Afghans and Tamils from Sri Lanka.

Thousands of Mandeans settled in Sydney's Liverpool area in the wake of the US invasion of Iraq nearly 20 years ago.

They also believe in the spiritual power of baptism and honour St John the Baptist as an important religious figure.

Speaking an Aramaic dialect believed to be the language of Jesus, the matriarchal community regularly performs baptisms in the Georges River dressed in white tunics.

Mr Nashmi is also building an almost scarecrow-like 1.8m bamboo structure emerging from the waterway, representing the body, mind and spirit in an artistic take on the death rituals of his people.

"We always return to the river. Clay representing the body eventually goes back to its origin," he says.

River Project artistic co-director Jiva Parthipan, who also works with the NSW Service for the Treatment and Rehabilitation of Torture and Trauma Survivors, says he wants to move refugee narratives beyond the hardship of forced migration from their home countries.

"I believe as future Australians, their cultural practices need to be explored in a nuanced manner with all other communities to redefine Australia," he says.

Mr Parthipan is bringing together Mr Nashmi, the Indigenous Jannawi Dance Clan along with a local Aboriginal elder, classical Indian singers and dancers, and members of the NSW Barefoot Water Ski Club in a collaboration exploring what the river means to those they represent.

"There is one river but it is embodying these simultaneous histories of four different local communities who are re-imagining and layering this river with their own heritages," he tells AAP.

Soulful ancient southern Indian melodies sung by second-generation migrant Namrata Pulapaka are also part of Saturday's program.

Carnatic music is an ancient art form handed down through an oral tradition to multiple generations over hundreds of years, she says.

The intricate musical scales called raga each "evoke a different sort of emotion".

"You may not understand what the words are," she says.

"But it's something that unites people and strikes a chord with them."

Ms Pulapaka says the sacred significance of the Ganges River is kept alive within Australia's Indian diaspora, with countless migrants having laid roots in western Sydney.

More than 720,000-strong nation-wide, they number second only to English expats.

Cremation in Hinduism is an essential religious practice of mourning those who have died with their ashes being washed down the river, Ms Pulapaka says.

"There's actually an area (on the Georges River) that's been dedicated to that, which is very inclusive.

"It's sort of like going back to nature."

Australian Associated Press