The Red Hill bushfire has destroyed a cottage in Wandoo Heights nature reserve and three sheds but DFES says aircraft and firefighters saved homes in the northern part of the fire area that were surrounded by bush.

On Thursday morning WA Police said the arson squad and the fire investigation officers were still waiting for the area where the fire is believed to have started to cool down so they can continue their work, so at this stage the cause of the fire is undetermined.

At a community meeting held at Baskerville Memorial Hall on Wednesday DFES incident controller Murray McBride said while the bushfire, which had burnt about 690ha of land, had been downgraded to a watch and act it was still not contained or controlled.

Mr McBride said DFES was hoping to get people back to their homes on Thursday.

When the bushfire was reported about 2.39pm on Tuesday, March 19 it was near Toodyay Road.

On Thursday morning DFES said roads to the east of Campersic Road would remain closed until hazardous tree work, site inspections and risk assessments had been undertaken.

The closed roads included Range Road, Macham Road, Cymosa Street, Hardwick Road, east of Campersic Road, Williams Street, east of Campersic Road, Padbury Avenue, east of Campersic Road Loton Road, east of Campersic Road.

In relation to crews having to stop using heavy machinery to build containment lines, Mr McBride said right from the start they got a list of critical infrastructure in the area and

Indigenous liaison officers came out and worked with them to make sure they didn’t do any damage.

The easterly winds fanned the blaze towards Wandoo Heights, 22ha of largely virgin bushland that was gifted to the City of Swan in 1988.

City of Swan Mayor Tanya Richardson said it was a poignant moment for many city staff and residents.

“Wandoo Heights is a special place with a special history and although the bushland can regrow, the cottage cannot,” Mayor Richardson said.

“That property has been maintained with so much care over the years and it’s sad to see a piece of local history lost.

“Once we have the all-clear, our staff will go into the area and start assessing the environmental impacts of this fire.”