A deep sinkhole appeared in Lynn Reserve, Bayview, over the weekend close to part of the learn-to-ride circuit. It was spotted and reported by a local resident out walking her dog. Council fenced off the site and are investigating the cause. Preliminary inspection indicates that the sinkhole occurred on top of a large corrugated iron pipe which is showing incorrectly in Council’s system as a concrete pipe. CCTV inspections are underway. 
Please take care in the area and don’t go through the fence.
Here is a photo montage supplied by the contractor.