THE first time the Swan Canning Estuary was tested for toxic firefighting foams was in December 2016, according to the Department of Biodiversity, Conservation and Attractions.
A department spokeswoman also said although the two dolphins found dead in the Swan River in August this year had been affected by fishing line entanglements they would also be tested for per- and poly-fluoroalkyl substances (PFAS).
“DBCA has a collaborative project with Murdoch University to investigate dolphin health and will undertake contaminant testing on these animals as part of that longer-term project,’’ she said.
The department has 20 routine monitoring sites throughout the Swan Canning Estuary and 26 sites within its sub-catchments where water testing is carried out.
“Within the City of Swan municipal boundary there are 11 catchment and two estuary monitoring sites.
Monitoring sites in the sub-catchments between Pearce air base and the Swan River were last sampled in June.
“There are two monitoring sites on the Ellen Brook located near Almeria Pde, Upper Swan and West Swan Rd, Belhus.’
“No catchment monitoring sites are located within the Shire of Mundaring, however three sites are located on streams or drains that drain from sub-catchments largely located within the shire.’’
She said it should be noted that routine monitoring samples were only collected when the stream or drain was flowing and so data points were not available for every stream or drain for every monitoring round.
No monitoring sites are located within the City of Kalamunda, however four sites are located on streams or drains that drain from sub-catchments that extend into the City of Kalamunda municipal area.
In December last year Environment Minister Stephen Dawson said that preliminary sampling of black bream and blue swimmer crabs in the Swan Canning Estuary had been carried out in June and that further sampling of black bream, blue swimmer crabs and western school prawns had started in November and that the results would be available early this year.
She said sampling of black bream and blue swimmer crabs was completed in December 2017.
“[But] despite extensive sampling in December 2017 no western school prawns were caught.’’
A report on PFAS in surface waters and biota of the Swan Canning Estuary and its catchment is being prepared and a final report is expected later this year.
By Anita McInnes