The sources of an awful smell plaguing several southern suburbs have been identified.
The Department of Water and Environmental Regulation received over 750 complaints from residents in Madora Bay, Lakelands, Karnup, Singleton and Secret Harbour this month alone, prompting an investigation into what was causing the smell.
"The department responded quickly and conducted extensive field odour surveys, both during the day and at night. During surveys late last week the department identified two companies in Nambeelup (C-Wise and CM Farms) to be a source of the odours identified in the community," a DWER spokesperson said.
"C-Wise accepts liquid waste and produces compost, while CM Farms operates a piggery."
Both companies have since been issued with an Environmental Protection Notice, which requires them to investigate the odour and rectify it.
They have 14 days to provide preliminary investigation results.
"The department is also investigating potential offences committed by C-Wise and CM Farms in respect of the odours generated. Any offences identified will be dealt with in accordance with DWER’s Compliance and Enforcement Policy," the DWER spokesperson said.
"The department is grateful for the community reporting on-going odour impacts, which facilitates our investigation to identify odour sources."
People impacted by odour can report it through DWER’s 24-hour Pollution Watch portal at How to report odour or call 1300 784 782.
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