Sewage overflow in Perth's southeast

Perth residents are being warned to steer clear of part of the Canning River following a sewage overflow in the city's southeast.

The public should stay out of the water and not paddle or swim upstream of the Kent Street Weir, WA Health says.

The river has not been closed, but warning signs have been erected following the overflow near Astley Street in Gosnells.

WA Health says it can take 48 to 72 hours for a water body to return to a safe condition after a sewage overflow.