POLICE are pondering the next step as the search for the body of drowned Ipswich teenager Duncan Wilmott reaches the one-week mark.
Despite days of scouring beneath the surface of Aqua Lake - the water-filled quarry that claimed Duncan's life last Monday morning - police have been unable to recover the 16-year-old's body.
Police divers are only able to descend to a depth of about 30m, which severely restricts the scope of the search, given that the lake reaches 80m in some places.
District Duty Officer Senior Sergeant Robbie Goodger said police were now waiting to see if Duncan's body would resurface, but there was no certainty.
"We will assess the situation again this afternoon and at some point we will need to decide if further intervention is needed," he said.
Among the options that police might consider, would be calling in more specialised divers from NSW, who can go down to 50m depth.
The Navy is also an option, with a remotely-controlled submersible vehicle able to descend to about 100m.
Snr Sgt Goodger said any decisions involving further intervention would likely be decided at a higher level.
Family of the missing teen and their supporters are now calling for authorities to drain the lake.
A Facebook page called Drain Aqua Lakes Quarry for Duncan has attracted about 3400 supporters.
Ipswich police are not able to make a call regarding the draining of the lake, however it is understood that an effort to drain a neighbouring quarry several years ago - in search of the body of murdered Ipswich woman Dulcie Birt - proved extremely expensive and ultimately fruitless.
The quarries are fed by underground water and can replenish while water is being pumped out - especially in the event of heavy rain.
Authorities are also limited in where they can transfer the water, as it is ridden with contaminants.
"The water goes into the next open cut hole further down - you can't pump the water into a river because it is contaminated. The water has a high salt content and the pH is very acidic," Snr Sgt Goodger said.