Authorities have issued a stern warning for all marine vessels to avoid the 300-metre-wide sand bar caused by ex-Tropical Cyclone Seth on the northern tip of Bribie Island after two people almost drowned.
Authorities responded to five calls for help last weekend, including having to rescue two people whose jet skis had capsized due to the sheer force of the raging water.
One person of those rescued was dragged 1.5km out to sea and brought back in by police. The other person, who was part of a jet ski group, was picked up by the Coastguard.
Caloundra Coastguard Commander Roger Pearce says the sand bar is especially dangerous on the outgoing tide due to floating debris, shifting sand bars and strong tidal flows.
“At full tide it is like any other coastal bar, but the Harbour Master has issued a very explicit warning stating when it is low tide, do not go anywhere near it,” he says.
“It hasn’t been declared a coastal bar yet because it is only two weeks old and hasn’t been surveyed, so until we understand it more, we need to treat it with care.
“We don’t know where the sand is accumulating, and we can’t be sure of the depth, which is why we are asking people to stay clear.”
Commander Pearce says the gushing water is like a “washing machine”, with the water travelling in a circular motion.
“Once the tide runs out, a massive plume of water will go through that passageway running about six to eight knots,” he says.
“Waves between 1-2m are knocking people off their jet skis, which is what we saw on the weekend. It doesn’t matter how good a rider you are, you will get knocked over.
“People won’t be able to swim against it, and they will be pulled out to sea.”
Mariners are also being reminded that lifejackets are compulsory for everyone crossing coastal bars in open boats under 4.8m and this safety measure is recommended while authorities formalise a potential new bar crossing.
Commander Pearce says the next destructive event will be during the upcoming spring tides between January 31 to February 3, and is urging everyone to take care.