Pile length is determined by bearing pressure.
Obviously because of years and years of pelican sh$t they have to be long enough to get through all the crap
I wouldn't be surprised if the piles are 25 to 30m long given that we've just installed 25m piles at Loganlea, which has probably similar geotech properties to Redcliffe i.e. mush & no rock founding level.
End of lesson
