Emergency services have renewed their appeal for help to find Blackheath man David Bush who went for a bushwalk on Saturday, May 23 and hasn't been seen since.
NSW SES volunteers from BSAR and Blue Mountains Units are continuing to assist the NSW Police with this search.
To save time of deployment, some of their remote teams are staying overnight in the Grose Valley. The SES is planning to continue to assist the Police in this operation over the coming weekend
Extensive land and air searches are continuing, with the assistance of SES, NSW Ambulance, the Rural Fire Service, and specialist police officers.
Mr Bush, aged 75, was last seen walking down the Horse Trail track from Evans Lookout at Blackheath about 9am on May 23. The experienced bushwalker told family he was going for a day walk.
Carol Ryan is the deputy commander of the NSW SES Bush Search and Rescue Unit, and she says about 90 of their members from all over the state have joined police in scouring the Grose Valley from Evans Lookout, right the way through to Victoria Falls at Mt Victoria.
"It's a big area. He is an experienced bushwalker, 75, but very fit. You can't predict how far he's gone," Ms Ryan said.
They are trying to cover as many trails in the area as possible.
Although most of the walks in the Grose Valley remain closed, walkers have still been accessing the area, and emergency services are urging these people who may have seen Mr Bush, to contact Crime Stoppers.
"Don't be afraid to call Crime Stoppers to help us," Ms Ryan said.
After four days of searching in fog, rain and mist, there has been no sign of Mr Bush.
"It's quite a mystery to us ... we've gone and had a look at all the places he would like to see," Ms Ryan said.
"The teams have found it has been a bit warmer in the valley where they've been working. The sun [on Wednesday] has helped buoy our spirits a little bit."
Mr Bush is described as being of Caucasian appearance, about 175cm tall, with a thin build and grey hair.
He was last seen wearing black pants, black jacket and a black beanie, and was carrying a blue backpack.
Anyone with information about Mr Bush's whereabouts is urged to contact Crime Stoppers: 1800 333 000 or https://nsw.crimestoppers.com.au.
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