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Old 19-04-2013, 00:46   #1
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Uncharted Reefs!

Hi All,

last year cruising we came across two yachts that nearly had a fatal meeting with uncharted reefs but didnt due to forward facing sonar and we heard on the radio one that did and sank, all in fiji.

I just found this list of uncharted reefs in tonga and fiji. Are there more of these lists out there for other parts of the world?

I'm going to add this into the Welcome to Yachts in Transit | Yachts in Transit website so you can give your position and it will tell you what direction and how far these are from you and their location in an email back to you. So if you email [uncharted]200 you'll get back stuff within 200 miles like this:

23miles N Volcano South Hope Reef. GPS 19 02 S 174 41 W
27 miles NW 3 nm diameter. GPS 18 48 S 175 14 W



If there are more of these lists around I would love to get my hands on them so I can add them to the system.
Tonga Fiji list.
COMMODORES CHUCK HOULIHAN AND DIANNE CLARK
UNCHARTED REEFS IN FIJI AND TONGA, AS OF JUNE, 1994
1. 18o23S 176o33 W
2. 18o44S 175o22 W
3. 18o45 S 175o22.24 W
4. 18o48 S 175o14 W 3 nm diameter.
5. 19o02 S 174o41 W Volcano South Hope Reef.
6. 19o10 S 175o07 W
7. 19o24 S 176o30 W
8. 19o27 S 176o33 W 4 nm diameter.
9. 19o27 S 176o35 W
10. 19o28 S 179o48 W Ono'Ilau 1.4 nm WNW of charted position
11. 19o30 S 179o36 W Vuata Vatoa Shoal 1.3 nm NW of charted position.
12. 19o31 S 177o24 W
13. 19o31 S 179o36 W
14 19o32 S 177o35 W 2 fathoms over.
15. 19o41 S 176o36 W
16. 19o52 S 176o37 W
17. 19o52 S 176o39 W
18. 19o54 S 176o32 W
19. 19o56 S 177o12 W
20. 19o56 S 177o35 W
21. 20o12 S 177o12 W
22. 20o15 S 177o13 W Discolored water 1958.
23. 20o16 S 176o00 W 3 nm diameter.
24. 20o17 S 177o32 W
25. 20o17 S 178o37 W
26. 20o20 S 176o00 W 3 nm diameter.
27. 20o20 S 177o15 W Shows 8.9 nm from N-S and 3.4 nm E-W
This information was supplied to DANCING WAVE, ex-naval vessel in Vava'u, Tonga in 1991.
ADDITIONAL UNCHARTED REEFS/ VARIOUS SOURCES
28. 13o24 S 166o12 W
29. 18o11 S 178o34 W Sea-mount position doubtful.
30. 18o44 S 176o35
31. 19o01 S 174o47 W
32. 19o13 S 175o19 W
33. 19o25 S 179o35 W
34. 19o29 S 177o26 W
35. 19o40 S 176o00 W
36. 19o49 S 176o32 W
37. 19o51 S 176o31 W
38. 19o55 S 176o31 W
39. 19o59.90S 167o44.55 W Wreck.
40. 20o14 S 177o13 W
41. 20o18 S 177o12 W
42. 20o19 S 178o44 W
43. 20o21 S 177o33 W
44. 32o19.45S 179o00.55 W Yacht hit in 1993.
45. 19o45 S 178o13 W Wreck.
46. 18o43 S 176o30 W
47. 18o47 S 175o17 W
48. 19o03.04S 169o55.29 W
49. 19o15 S 175o19 W
50. 19o27 S 176o30 W
51. 19o34 S 179o38 W
52. 19o43 S 176o33 W
53. 19o50 S 176o32 W
54. 19o54 S 176o32 W
55. 19o56 S 177o36 W
56. 20o03 S 177o37 W
57. 20o15 S 177o12 W
58. 20o19 S 177o35 W
59. 20o20 S 176o00 W
60. 22o20 S 176o00 W


cheers
mike
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Old 19-04-2013, 15:19   #2
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Re: Uncharted Reefs!

I did a quick check with the first 4 + one more, on your list compared to the latest NZ charts for the area. Freely available in the BSB3 format, by the way. All were marked.

I note that uncharted reefs, is an area where knowing a bit about old Polynesian wave reflection techniques pays of. If you are able to "tune in" to, and analyze the swell, you may get an advanced warning, even of an unmarked reef.

Thomas
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Old 20-04-2013, 18:29   #3
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Re: Uncharted Reefs!

Quote:
Originally Posted by cagney View Post
I did a quick check with the first 4 + one more, on your list compared to the latest NZ charts for the area. Freely available in the BSB3 format, by the way. All were marked.

I note that uncharted reefs, is an area where knowing a bit about old Polynesian wave reflection techniques pays of. If you are able to "tune in" to, and analyze the swell, you may get an advanced warning, even of an unmarked reef.

Thomas
Hi Thomas,

Thanks for checking those, I checked a few out on our 2010 garmin charts and none appeared. Most likely why people are still hitting things, not using the latest charts and/or just relying on their electronic charts. I think it would be a good feature to add in and the system can easily handle it but I'll have to do it in the next month or so.
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Old 20-04-2013, 18:38   #4
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Re: Uncharted Reefs!

Frankly, I'm not sure if "the latest charts" will be more accurate than older raster and paper charts. We have seen reports on here of charts and other obstructions disappearing on various new digital charts, like the recent instance where Next Life piled up on the reefs near Georgetown in the Bahamas.
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Old 20-04-2013, 18:57   #5
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Re: Uncharted Reefs!

Particularly around Tonga. The charts have not been updated and no surveys done for years. Often the reefs are on the chart, just in the wrong place. The electronic charts are taken from the paper charts so if the paper is wrong, the electronic chart is too.
Also, in Fiji some of the electronic (C-Map) charts are accurate on one scale but not on another.
My personal experience in Fiji last year was to hear of a lot of yachts hitting reefs and I'm sure it was because they expected the electronic charts to be 100% accurate and forgot (or never new) some of the basic tenets of good seamanship.
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Old 20-04-2013, 19:08   #6
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Re: Uncharted Reefs!

And then there's the recent US Navy flub up in the Philippines blamed on bad charts.
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Old 20-04-2013, 19:22   #7
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Re: Uncharted Reefs!

Quote:
Originally Posted by Albro359 View Post
Particularly around Tonga. The charts have not been updated and no surveys done for years. Often the reefs are on the chart, just in the wrong place. The electronic charts are taken from the paper charts so if the paper is wrong, the electronic chart is too.
Also, in Fiji some of the electronic (C-Map) charts are accurate on one scale but not on another.
My personal experience in Fiji last year was to hear of a lot of yachts hitting reefs and I'm sure it was because they expected the electronic charts to be 100% accurate and forgot (or never new) some of the basic tenets of good seamanship.

How fast do reefs grow in that area? Seems to me that charts that haven't been updated and rapid growth might make for a bad combination.
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Old 20-04-2013, 19:43   #8
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Re: Uncharted Reefs!

Reefs grow slowly, but the subsea volcanoes sometimes grow quickly.
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Old 21-04-2013, 03:55   #9
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Re: Uncharted Reefs!

@Sailfish
Quote:
Thanks for checking those, I checked a few out on our 2010 garmin charts and none appeared. Most likely why people are still hitting things, not using the latest charts and/or just relying on their electronic charts. I think it would be a good feature to add in and the system can easily handle it but I'll have to do it in the next month or so.
Yes a good idea. It's also very easy to create a gpx layer of all the "unchartered reefs", for display in OpenCPN and other gpx compatible pc programs & plotters.

@Kettlewell
Quote:
Frankly, I'm not sure if "the latest charts" will be more accurate than older raster and paper charts. We have seen reports on here of charts and other obstructions disappearing on various new digital charts, like the recent instance where Next Life piled up on the reefs near Georgetown in the Bahamas.
True. Vendors like Navionics, can't be trusted to have the same serious and thorough approach to chart making, as for example UKHO. Navionics, for example, refuses to state where their faulty data, near Gorgetown, came from and how it ended up on their chart.
CM93 v2 charts are on the same level as Navionics. OK in some areas but very bad in others, and generally can't be used without an extensive cross reference with other sources.
I wonder if the Jeppesen issued Cmaps are better?
What about the reliability of Garmins cartography, and their attitude towards errors?


@Albro359
Quote:
Particularly around Tonga. The charts have not been updated and no surveys done for years. Often the reefs are on the chart, just in the wrong place. The electronic charts are taken from the paper charts so if the paper is wrong, the electronic chart is too.
Also, in Fiji some of the electronic (C-Map) charts are accurate on one scale but not on another.
My personal experience in Fiji last year was to hear of a lot of yachts hitting reefs and I'm sure it was because they expected the electronic charts to be 100% accurate and forgot (or never new) some of the basic tenets of good seamanship.
Not quite true. The Kiwis actually have mad some recent Tongan Surveys. Part of the approaches to Vava'u, comes to mind. Apart from that, I agree with you.

I cruised through the Tonga/Fiji area numerous times in the 80ies and 90ies, before the modern chart plotters even existed. There were not a lot of yachts hitting reefs. We all knew that there were areas to be avoided and, specially nighttime, planned our routes to avoid these with a safe margin. For daytime navigation, unchartered reefs did not matter that much, as eyeball navigation in coral areas is a must.

Thomas
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Old 21-04-2013, 05:10   #10
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Quote:
Originally Posted by cagney View Post
@Sailfish

Yes a good idea. It's also very easy to create a gpx layer of all the "unchartered reefs", for display in OpenCPN and other gpx compatible pc programs & plotters.

@Kettlewell

True. Vendors like Navionics, can't be trusted to have the same serious and thorough approach to chart making, as for example UKHO. Navionics, for example, refuses to state where their faulty data, near Gorgetown, came from and how it ended up on their chart.
CM93 v2 charts are on the same level as Navionics. OK in some areas but very bad in others, and generally can't be used without an extensive cross reference with other sources.
I wonder if the Jeppesen issued Cmaps are better?
What about the reliability of Garmins cartography, and their attitude towards errors?

@Albro359

Not quite true. The Kiwis actually have mad some recent Tongan Surveys. Part of the approaches to Vava'u, comes to mind. Apart from that, I agree with you.

I cruised through the Tonga/Fiji area numerous times in the 80ies and 90ies, before the modern chart plotters even existed. There were not a lot of yachts hitting reefs. We all knew that there were areas to be avoided and, specially nighttime, planned our routes to avoid these with a safe margin. For daytime navigation, unchartered reefs did not matter that much, as eyeball navigation in coral areas is a must.

Thomas
I'm heading to these islands in a few months, it's a good reminder not to get lulled into relying to much on technology. Malpelo (between panama and galapogos) island was a mile or more out with the latest navionics on raymarine e7. It is the nights when I rely a lot on charts, i always use at least two different systems but that still doesn't mean it's marked.
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Old 21-04-2013, 05:52   #11
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Re: Uncharted Reefs!

I've seen the same problem down in the Caribbean. There are some offshore reefs near the Honduras-Nicaragua border and they are noted to possibly be miles out of position on the old paper charts. Because of this I avoided the area by many miles, but someone else I met using electronic cartography decided to try and anchor in their lee for some reason and managed to pile up on the reef. Luckily they had an aluminum boat and were able to get off. I saw numerous instances down in the San Blas Islands of things that were not charted accurately. For that matter, it doesn't take long to find errors on electronic charts here in the USA, where for the most part the old raster NOAA charts and paper charts are quite accurate.
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Old 21-04-2013, 06:02   #12
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Re: Uncharted Reefs!

Quote:
Originally Posted by gunnado View Post
I'm heading to these islands in a few months, it's a good reminder not to get lulled into relying to much on technology. Malpelo (between panama and galapogos) island was a mile or more out with the latest navionics on raymarine e7. It is the nights when I rely a lot on charts, i always use at least two different systems but that still doesn't mean it's marked.
Talking about Malpelo....
Malpelo Chart 521 is the official Columbian Chart. How does this chart agree with your gps data?

Thomas
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Old 21-04-2013, 15:50   #13
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Re: Uncharted Reefs!

I dont have access to my E7 but i do have it on navionics on my Iphone and it is different. Navoinics shows the south east tip of the mainland to be 3'58.790n 81'34.285w instead of your chart shows it at approximatly 4'00.0n 81'36.2w. i would use rely on your official chart as the most accurate.

its been a wile and i measured your chart by eye, so please correct me if i am wrong?
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Old 21-04-2013, 16:01   #14
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Re: Uncharted Reefs!

We have both Garmin, C-Map and Navionics charts on board and when we were cruising Fiji, none of them were completely accurate. Many cruisers would cache screen shots from Google Earth and then overlay them onto their computer-based navigation program. We had difficulty with that - for some reason, our computer would lock up whenever we used Google Earth. Regardless, many cruisers who did use it were able to navigate the Fijian waters with a high degree of confidence, though the area still demands a watchful eye. Still, despite the poor navigation charts, we feel that Fiji is not to be missed as a cruising destination.

Fair winds and calm seas.
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