The spill is believed to be a large quantity of cooking oil.
The Department of Water and Environmental Regulation’s Pollution Response Unit is leading the investigation, working with the City of Stirling, Water Corporation, Department of Biodiversity, Conservation and Attractions (DBCA) and the Western Australian Seabird Rescue group (WASR).
The spill is impacting wildlife, with a number of pelicans cleaned and released by WASR. DBCA is assessing the impact on other wildlife.
Water Corporation is containing the spill with a floating boom and City of Stirling inspectors are tracing the spill’s path to try to discover its source.
DWER Senior Manager Pollution Response Ken Raine said what appeared to be cooking oil has been spotted in the lake over the past month, which means someone might have caused the pollution on more than one occasion.
“It’s not known exactly how much oil has spilled into the lake or where it has come from, but it is a substantial pollution event over a period of time,” Mr Raine said.
“We will be deploying drones to assess the extent of the spill and whether we can pinpoint the source, which could be a commercial kitchen due to the amount of oil spilled.”
Anyone with information should contact DWER’s 24-hour Pollution Watch Hotline on 1300 784 782 use the DWER online reporting form, or call Crime Stoppers on 1800 333 000.
