The first rule is that you shouldn't believe everything you read! The first news reports labeled it as a "sinkhole". There were detailed diagrams and descriptions from "geotechnical engineers" about how and why a sinkhole occurs and what would be done to see if there was a possibility of another one occurring close by. It was another two days before another geotechnical engineer said that it may not have been a sinkhole but might instead have been a "near shore or peninsular landslide". It was not until the end of the week that the Gympie Times reported that there was a similar incident reported in a Brisbane paper in 1873. It was then speculated that it was the result of a "tidal scour" - erosion due to tidal movement.
I must say I wonder how carefully the various geotechnial experts were quoted!
I am not an engineer but I do wonder why more attention has not been paid to the fact that all the land at that point and for some way around is simply sand brought in by the tide over the years. Also wet sand is not stable around water. All the washouts that I have seen or heard of have been beside the channel that goes between Inskip Point and Fraser Island. Here are a couple of photos of that water.
I am told that the really deep water in that channel changes around every tide and boat skippers take very careful note of the readings on their depth sounders. This channel drains all the water from the Sandy Strait. The Strait stretches north to Harvey Bay and half of that northern portion drains out there. However, all of the southern part of the Strait drains through this channel. This is the part that I know and kayak around. Here is part of a google earth image of this southern part. I used the google rule to do a rough measurement and it is more than 22kms in length.
On the more southerly parts where I usually kayak the tide pull is not strong but it certainly makes a difference if you are kayaking for a few kilometers. Most of the southerly part becomes sand flats at low tide - most of the water drains out! This photo is of about 6 kms of the more southerly part of the Strait.
This photo is of the more northerly part - Fraser Island is in the distance.
That is a lot of water draining in and out twice a day. I have occasionally seen some people kayaking over the channel - but I have not done so as I have no idea of when the really slack water happens on the tides around there.
I am still feeling very sorry for the owners of the caravan and 4 wheel drive vehicle that got swallowed up on the night of the washout. The recent reports I have heard said that it was impossible to get it out. I saw an interview with them on a news report and they were retirees that had sold up their house and were traveling around Australia in that van and vehicle. Poor people!
As well as all the shorebirds, Inskip Point is a good place to watch the tern species that are around this area. For most of the year I can see Caspian terns, Gull-billed terns, lots of Crested Terns and the occasional Little tern. Then in the summer months we have literally 1000's of migratory terns - Common terns, Little terns and the occasional White-winged Black terns. Here are photos I have taken at Inskip with the birds resting on the sand flats at low tide.