Michael McFadyen's Scuba Diving Web Site
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St George Scuba Club
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Dive Sites
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Sydney Shipwrecks
Kelly Talking on ABC Sydney about Shipwrecks
NSW Dive Sites
Sydney Shipwreck Summary
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Australian Dive Sites
Overseas Dive Sites
Aircraft I have Dived
Old Bottles

Dive Related Equipment
Shearwater Predator and Heinrichs Weikamp OSTC 2N
Uwatec Aladin Dive Computers
Apollo AV1 Underwater Scooter
Bauer Compressor
DIY Oxygen Stick - Nitrox
GoPro HD Hero Video Camera
My Camera Setup
Purchase of New Dive Boat
My Dive Boat - Mak Cat
My Old Dive Boat - Le Scat
My Dive Gear
GPS and Diving
Make Your Own Car Tank Rack

Marine Life
Rarer Sydney Marine Life
Bare Island Pygmy Pipe Horses
Bare Island Sea Horses
Bare Island Nudibranchs
Bare Island Marine Life
Encounter with Southern Right Whale and Calf

Other Dive Info
How Weather Affects Diving in Sydney
Visibility and Wave Averages in Sydney
Waves and Diving
Diving Weather and Sea Conditions
Tide Tables
Dive Accidents and Incidents
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Noel Hitchins 1951-2005
Lloyd Bridges - Mike Nelson in Sea Hunt
My Yachting Adventures
Below is a list of links to the main pages about my yacht, Catlypso and My Yachting Adventures:
  • Purchase of Catlypso
  • Details about Catlypso
  • Cleaning/Repairing Catlypso
  • My Yachting Adventures.
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    Michael's 4WD Trips
    Click here for a list of my Four Wheel Drive and Camping Trips.
    Current Kareela Weather
    A summary of the current weather conditions at my house at Kareela, Sydney, is below. Click here for more Detailed Diving Weather and Conditions. Weather from Michael McFadyen's Tempe Weather Station

    Conditions at
    23:49 on 23/1/17

    Temperature 25.6°C
    Humidity 65.0%
    Barometer 1003.4hPa
    Rate -0.3hPa/hr
    Wind Speed: 0 km/hr
    Wind Direction S
    Rainfall for Today 0.0mm
    Rainfall last hour 0.0 mm
    Rainfall last 24 hours 0.0 mm
    Rainfall at Start of Month 814.6 mm
    Rainfall this Year 827.0 mm
    Today's Extremes
    High Temperature 31.2°C at 15:48
    Low Temperature 20.9°C at 6:27
    Peak Wind Gust 0km/hr at 0:00
    Weather from Michael McFadyen's Kirrawee Weather Station
    Yesterday's Extremes
    High Temperature 27.5°C at 17:11
    Low Temperature 19.8°C at 6:29
    Rainfall at Start of Yesterday 827.0 mm
    Rainfall at End of Yesterday 827.0 mm
    Weather from Michael McFadyen's Tempe Weather Station
    Astronomical Data
    Sunrise 5:06
    Sunset 19:05
    Moonrise 1:09
    Moonset 15:04

    Home Brewing
    Click here for an article about Home Brewing.
    Sydney Dive Site Hints
    "Grey nurse sharks can be seen at Magic Point"
    JD Reef (North)
    In October 2017, two new artificial reefs were installed off Royal National Park on the southern side of Sydney. This was organised by NSW Department of Primary Industries. It is intended for fishing, but there is nothing that prohibits scuba diving on it as it was paid for by the Transport for NSW Port Botany Boating and Fishing Infrastructure Fund (which does not appear to be from monies from fishing licences. It is said to be the largest artificial reef complex in Australia, but this seems to me to be a very loose interpretation of what constitutes a reef (see later).

    The reef has been named JD Reef. This is named after John Dunphy who apparently owned the Australian Shimano rights.

    The reef is in two sections, the northern one and the southern one (as they call them). The centre of the northern reef is located 540 metres south-east of Barrens Hut and the southern reef is 950 metres south of Barrens Hut (and 610 metres south-west of the northern reef.

    These reefs have been constructed in a very strange way. Rather than put all the structures together or even very close to each other, they are in a pattern, well separated from each other. Each reef structure is a Greek cross shape, that is, each arm is the same length. Each one is 100 metres east to west and 100 metres north to south.

    Each reef structure consists of 18 modules. The modules are pyramid shaped concrete structures (sort of like an Eiffel Tower), four metres square and five metres high. They weigh 25 tonnes each. Ten of the modules have steel structures bolted to one side that increase their height to nine metres. They are basically hollow structures that have lots of large spaces inside.

    Each reef has five parts. The middle part has four modules. The parts to the north and south (probably about 30 metres away), also have four modules. The parts to the east and west (also about 30 metres away) only have three modules. The modules in each part are about 7 metres away from each other. See the diagram below.

    JD ReefJD Reef
    The location of the two parts of the reefThe layout of the northern reef. The southern one is similar.

    Each reef is about 900 metres from the shore. The northern one is centred around S34⁰ 05.659' E151⁰ 10.657' (datum WGS84). In November 2017, about four weeks after the reef was finally all in place, we went out and decided to have a look and see what we could find. We motored to the GPS co-ordinates above and at first could not find anything. However, after running around a bit we picked up a structure on the depth sounder. It was not all that big, two hits. At this time we had assumed that the reefs were constructed of closely packed modules. We expected to run over a solid reef for about 80 to 100 metres.

    We went around and around and finally anchored on the only one we managed to find. The depth was 28 metres. We hooked in and then I and my buddy descended. The anchor was on a cross bar of one of the modules. We left it there. The modules are quite large, standing high. The sand around and inside the modules has been cleared out a bit, so it is deeper there than the surrounding sand.

    From the map above of the northern reef, we think that we were anchored on the western most section. Some of the modules also have steel poles attached to the cross bars, extending the height by a few more metres. One of the modules here had one attached. From the module were descended on, we could see another one about 7 to 10 metres away. After swimming round, we spotted a third module.

    We swam out away from each of the modules as far as we could before loosing sight of the module. We did not see any more. The modules already have some growth on them, small barnacles are all over the concrete surfaces. There was not much fishlife around, although there were plenty of small flathead on the sand. Inside some of the modules were a few fish. You can swim right inside them.

    As mentioned, the depth of this reef is about 28 metres on the sand. This limits your bottom time considerably. Although there was not much fishlife around, I can imagine that once the modules have more growth on them, they will start to attract more fish.

    We dived here now to see what they looked like so that when we come back in six or more months, we can compare them then to now. I also intend to come back sooner and link up the groups of modules to the centre group with ropes. I have some old ropes and will use them to connect the groups so that in future we can anchor on one and then go to the other four groups that make up each reef.

    At the moment, only worth a dive to see what they look like when they are new.

    Finally, it should be noted that this reef was established for fishing, so if you go to dive here and there are fishers on the reef you want to dive, you should go somewhere else. Generally, we intend to only dive the reefs on weekdays when there are hardly any fishers around.

    Copyright © Michael McFadyen 1990 to 2019
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    without any help from the Australian Dive Industry since 1996!