Saturday, November 19, 2016

The Wide Bay Bar - shifting sands

There are few spots on Australia's east coast that cause as much angst as the Wide Bay Bar, a pass between the Queensland coast and Fraser Island. 

It is managed by Maritime Safety Queensland and the Tin Can Bay Coast Guard, who offer advice about its safety and give yachties waypoints to help them stay in deep water, often between curling breakers on either side of the passage. There are also two leading lights; one on Hook Point on Fraser Island that guides vessels west, and the other on Inskip Point on the mainland.

I asked the Tin Can Bay Coastguard what the current waypoints are. He sent me this SMS. (19th Nov 2016)

Wpt 1 lat. 25 47.45 south.    long. 153  08.4 East. Brg to Hook Pt light 277.5 True. 

Wpt 2  lat. 25 47. 22 south,  long. 153  06.33 East, Brg to Inskip Pt leads 238 true.       
Please refer to NTM 101 T 2016 for further information.   The south bank sand bar is creeping across the centre line of the bearing to the hook point light, vessels should err to the north of the centre line by 100 to 150m of the inbound/out bound track to clear this position.

It turns out that the waypoints are the same as they were a year ago, in November 2015.

But the NTM (Notice to Mariners) is very interesting. Download it here.

It includes this chart of a survey done in March 2016.


The dark blue patches are the shallow spots.


If you follow the waypoints that are currently being given out, or if you follow the leading light on Hook Point, you will cross a shallow patch of 3 metres, which, if any sort of swell is running, may well crash your keel violently into the sand.

The authorities cover this by telling us to read NTM 101 (T) 2016, and "err to the north of the centre line by 100 to 150m".

The Hook Point light is set in foundations, and not easy to move. In its present position, it is leading vessels into danger, especially if their skipper has not studied the fine print in the NTM. Maybe the light should be switched off until it can be moved.

But the waypoints might easily be changed to guide vessels down a safe line. It seems strange to me that old waypoints are still being recommended.

I had a look at the chart from the March 2016 survey and tentatively suggest that better waypoints might be as follows:

WP1 25°48'.000S, 153°08'.400E
WP2 25°47'.000S 153°06'.750E


I suggest that you ignore the Hook Point light. Use these waypoints at your own risk.

PS. We crossed the Wide Bay Bar today, going out, using the green waypoints. We left at 8 am, two hours after low water, in a 15 knot easterly. We passed some breaking water on our starboard side, but went through none ourselves. I am pretty sure that we would have gone through breaking water if we had been following the official waypoints or Hook Point light, even if we had been 150 metres north of that line.

Until further notice, I suggest the green waypoints be used.

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