Very safe. The river is full of sharks, as are most tidal rivers, globally....and cobbler..and rays.. They have always been there
They are testimony to the fact that we really have little to worry about really.
Nothing wrong with being a little afraid though..all part of the excitement of enjoying nature at its finest!
Dont tell me that. I spent most of the weekend in waist deep water teaching my GF to windsurf and then recovering from messed up gybes on my 84L JP FSW.
Years ago (30 plus) I heard a a shark trying to munch on a horse someone was exercising in the river in MAYLANDS! But it's probably OK now as the sharks probably dead.
MUNCH MUNCH MUNCH
Grew up in rossmoyne so our past time was traversing the mt Henry freeway bridge and jumping the west side at the 4th light pole.
On one occasion me and a mate jumped at night ~11pm.
Swam to shore and scaled the bridge for another jump.
Looked down to jump and there was (what we calculated - dorsal to tail fin) an 8' bullshark.
Didn't jump again.
There has been at least one fatal shark attack in the Swan River over the years, and a few non fatal.
They are from bull sharks which take a liking to swimming up the river and have been responsible for attacks as far up as the Garret Road bridge near Guilford.
For some reason they call them Swan River Whalers but they are a type of bull shark.
They don't rip you to bits like a great white because they are not big enough for that, but they can chew a sizable hole in your arm or leg so that you die from rapid blood loss. 
You probably have more chance of getting run over by a pleasure boat.then getting mauled by a big fish with teeth.
A 1.5m shark is pretty much a sausage dog with fins, and about as dangerous.
MTFU SLSWA!
Bull Sharks are also in Sydney Harbour. Nothing to worry about.
www.news.com.au/technology/environment/map-of-shark-movements-on-australia-day-prove-animals-share-the-busy-waterway/news-story/31194fca532396e365571be4490b7c00
