The Shire of Toodyay in Western Australia's Wheatbelt region has been given a suspended fine for breaching the state's Aboriginal Heritage Act.

The shire was fined $8000, suspended for 12 months, in the Northam Magistrates Court on Monday after they failed to gain approval to work on culturally significant land, as well as disrupting the Waugul, a rainbow serpent pivotal to Noongar mythology.

The Shire of Toodyay, 85 km from Perth, employed contractors to conduct emergency repairs to waterway crossings without seeking prior approval. They were charged with 10 counts of damaging or altering an Aboriginal site but six were dropped with guilty pleas entered for the four other charges.

The ABC reported the court had heard the Shire breached the Aboriginal Heritage Act when contractors hired to undertake repairs to existing river crossings in Coondle and Bejoording in 2023 moved rocks in riverbanks with machinery.

The works disrupted the disrupted the Waugul, Department of Planning, Lands and Heritage prosecutor Lorraine Allen said, which therefore needed the consent from the Minister of Aboriginal Affairs and the Registrar of Aboriginal Sites.

The Shire of Toodyay failed to do this, with the statement of facts noting any change or alteration to the Waugul's home could cause the Avon River to dry up and cause harm to both the surrounding environment and people.

Magistrate Sarah Oliver said the offences were not insignificant or trivial, highlighting strong legal compliance was needed to maintain the preservation of Indigenous culture and heritage.

The legal representative for the Shire of Toodyay said the Shire was remorseful, the ABC reported, and the court action served as a warning. He said the Shire had increased training surrounding heritage requirements.

Contractor Glenview Nominees has pled not guilty to four charges, which will now go to trial. Two charges against Wacwil Landscaping and Earthworks were discontinued.