N= 68 40 000 N= 68 40 000 N= 68 48 000 N= 68 48 000 N= 68 56 000 N= 68 56 000 N= 68 64 000 N= 68 64 000 N= 68 72 000 N= 68 72 000 E= 7 52 000 E= 7 52 000 E= 7 60 000 E= 7 60 000 E= 7 68 000 E= 7 68 000 E= 7 76 000 E= 7 76 000 C CROWN COPYRIGHT RESERVED Department of Transport, W.A. 2010. March 2016, Edition 2. Produced by Cartographic Services, DoT, Western Australia. SEE RELATED PUBLICATIONS: Notice to Mariners (http://www.transport.wa.gov.au/imarine/coastaldata/), Symbols, Abbreviations and Terms (INT 1), Tide Tables, Sailing Directions. For surveys beyond this chart refer to RAN Charts AUS 83 and AUS 751. 1.0 1.5 2 3 4 5 6 7 8 9 10 15 20 30 SPEED (Knots) 0.1 0.2 0.4 0.6 1.0 2 4 8 10 15 20 30 40 50 6 DISTANCE (Nautical Miles) 6 10 15 20 30 40 50 60 90 120 180 TIME INTERVAL (Minutes) LOGARITHMIC NOMOGRAM SPEED - DISTANCE - TIME Example To find Speed, Distance or Time Interval, draw a line through any two factors, then interpolate for the unknown factor. eg. A distance of 10 nautical miles in 120 minutes means a speed of 5 knots. For further information, contact Department of Land Administration on (08) 9273 7133. The location of points on this chart are referenced to the Geocentric Datum of Australia 1994 (GDA94) and will differ by approx 200m to the same points shown on charts referenced to the Australian Geodetic Datum 1984 (AGD84). All depths and heights remain the same. 0 010 020 030 040 050 060 070 080 090 270 280 290 300 310 320 330 340 350 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 1°12'W 2016 (0'E) 030 060 090 270 300 330 120 150 180 210 240 M ID D L E C H A N N E L M o r n i n g R e e f Goss P assage N o o n R e e f Sh e l t e r R e e f B a r k e r P a s s a g e S u d a B a y P a s s a g e W e s t R e e f S o u th P ass a g e The Houtman Abrolhos is situated about 40 nautical miles west of Geraldton and comprises 122 islands clustered into three main groups. It is an extensive coral reef system that stretches for about 45 nautical miles north to south. The islands are low lying and do not present a very good radar picture. The name Abrolhos is derived from the Portuguese language, and means "OPEN YOUR EYES", which is exactly what you need to do when navigating in this area. The Abrolhos is a hazardous area and requires careful pilotage. The reef systems are steep, rising from relatively deep water, and can remain unseen until close by. Good visibility is necessary to navigate through the reefs. Visibility is impared when the sun is low or ahead and when the water is glassy calm. As swells or waves move in from the open ocean towards the Abrolhos, they are suddenly confronted by a rapidly rising seabed, causing them to break. An important factor in safe reef navigation is the skipper's ability to understand and interpret the conditions sensibly and objectively. When going out, if a big wave does rear up, get the boat's bow up fast and hit the wave at an angle of about 10 degrees off head on, with plenty of throttle. Back off the throttle when through and work out your approach to the next wave. Look for the lowest point of the wave and remember the correct angle of approach. When coming in through heavy seas, always concentrate on keeping your boat on the back of the wave, avoid surfing at all costs, and never get side on in the impact zone. Be careful when applying power in frothy waves as cavitation and loss of power may occur. If so, back off throttle until cavitation stops and reapply power gradually. Keep a close eye on the weather and watch out for unexpected changes, as the wind can change direction and blow strongly with little warning. The islands are low lying and offer little protection from the wind. The coral sand at the Houtman Abrolhos is generally very poor holding ground and dragging anchor here can be dangerous, especially at night. Geraldton Sea Rescue operate a 24 hour service and weather schedules are broadcast on VHF channel 72. The weather pattern is unaffected by the land and sea breezes of the mainland. During summer, south-easterlies prevail, and are constantly strong. During winter months, NW-W changes are preceded by northerlies and light winds. The Abrolhos is first in the path of any weather moving in from the west or northwest, and cold and warm fronts may reach the islands 24 hours or more in advance of weather bureau forecasts for the mainland. Always inform someone as to where you are going and when you will return. Call Geraldton Sea Rescue on 27mHz, VHF or HF radio to notify them of your intentions. Don't forget to let them know when you have returned and importantly, advise them if you have changed your plans. Minimum safety equipment you MUST carry Bilge pump or bailer or bucket ● Approved anchor and sufficient line ● Fire extinguisher for boats with inboard motors or liquid or ● gas filled appliances Suitable sized life jackets: SOLAS, Coastal or Australian ● Standards 1512 Two hand held red flares ● Two parachute distress rockets ● Two hand held orange smoke signals or one smoke canister ● Two-way marine band radio ● EPIRB ● Responsible skippers carry extra gear, and, although not prescribed, a good pair of polaroid sunglasses are essential for navigating around the reefs. All safety equipment MUST be maintained in very good condition and be accessible at all times. The Houtman Abrolhos and it's surrounding coral reef communities form one of Western Australia's most unique marine areas. The islands' environments - both marine and terrestrial - are very fragile, and need the protection of residents and visitors alike. The Abrolhos is part of the aquatic heritage of all West Australians - it is our task to ensure that we hand the islands, their fish stocks and their wildlife onto future generations, undamaged and still productive. No facilities or accommodation for visitors are available at the Abrolhos, and there are no sources of freshwater on the islands. Before setting out make sure that you have enough supplies and freshwater to last the length of your intended visit. Emergency medical assistance is available from the Silver Chain nurse on Rat Island (Easter Group) between 15 March and 30 June. Contact channel 16 on VHF. The Houtman Abrolhos Nature Reserve covers all 122 islands in the Abrolhos system. As such, by law, all wildlife is protected, and no domestic pets are allowed on vessels or at the islands. Landing is permitted on uninhabited islands, but lighting fires, camping and firearms are prohibited. Please take great care not to disturb nesting seabirds. If you do go ashore, it is better to walk along the shoreline, or well defined paths, rather than across the islands, as you may destroy seabird nesting burrows. When you visit the Abrolhos, remember - this is a special place that needs your protection. Private property - The residences, jetties and rainwater ● tanks of commercial fishermen on the 22 islands designated for their use are private property. You may land on the islands, but you may not use the facilities (including jetties) unless you have written permission on board your boat from the owner. You may not stay in fishermen's camps unless the owner is present. If you are unable to use a public mooring, please endeavour ● to anchor away from sensitive marine habitats, particularly coral and seagrass areas. Take your rubbish away with you - don't drop it in the water. ● Only take enough fish for your personal consumption. ● Take care not to disturb birds and other wildlife on the ● islands. Don't pump bilges in the shallows - the effluent can harm ● marine life. When diving, avoid standing on fragile corals - they break ● easily. A number of environmentally-friendly public moorings have been installed at sensitive marine sites and popular diving spots around the Houtman Abrolhos, including the Long Island Dive Trail and Fish Point. Instructions printed on the individual mooring buoys indicates suitability for day or overnight useage. Further moorings are planned for the future. The Abrolhos is famous for it's historic shipwrecks, the best known of which are the Dutch East India Company vessels Batavia (1629), on Morning Reef near Beacon Island in the Wallabi Group, and the Zeewijk (1727) on Half Moon Reef in the Pelsaert Group. So far, a total of seven historic shipwrecks have been discovered. Other wrecks are known to exist, but they are yet to be found. All wrecks, 75 years old or more, are protected under the Historic Shipwrecks Act 1976, which prohibits the removal of artefacts or wilful damage of any sort. By this means, the sites will remain better preserved for divers in the future. Refer to WA Maritime Museum for further information. A major development in managing the marine system of the Abrolhos occurred in 1994 with the introduction of Reef Observation Areas, with one such area being declared in each island group, including North Island. Except for the use of rock lobster pots, fishing by both recreational and commercial fishers is prohibited in the Reef Observation Areas. These regulations are intended to allow the recovery of finfish populations towards their original state, providing an area where divers can observe large fish that are not frightened by their approach. Your boat must be suitable for a long journey in open water. It must be seaworthy and have adequate buoyancy. You must carry the appropriate safety equipment and ensure all on board know how to use it. 11 7 9 8 3 4 1 5 5.0 13 LEGEND 6 0 Marsh and swampland Nature Reserve / National Park Railway, Clearance height, Bridge Clearance height, Overhead powerline River Major road Minor road Track Medical facility, Building Mean high water Mean low water Datum mark Cliff Rock shoreline Sand drift, Anchoring prohibited GPS validation point, Helipad, Groyne Car parking, Over-beach launching Boat ramp, Tide rips Parking for boats / trailers Mangroves, Foul ground, Marine farm Water, Fuel, Jetty, Safe anchorage Telephone, Public toilet Exposed wreck, Submerged wreck Hazardous submerged reef Reef which covers and uncovers Coral reef / outcrop, Breakers Rock awash, Underwater rock Sounding above Datum Danger line 2m contour 5m contour 10m contour Depth in metres and decimetres Approximate contour Submarine cable Anchorage area, No anchorage area No fishing, Pilot boarding location Speed limit boundary Water skiing boundary Prohibited area boundary Various limits Port Authority / Harbour boundary Recommended track Outfall Dredged area boundary Restricted area / Sensitive area Marine protected area LIGHT CHARACTERISTICS indicates lit navigation mark CARDINAL MARKS North South East Indicates safe water to the East West Indicates safe water to the West Indicates safe water to the North Indicates safe water to the South F Fl Fl( ) Q LFl Oc Iso = Fixed = Flashing = Group-flash = Quick-flash = Long-flash = Occulting = Isophase s m M = Period in seconds = Focal plane height above MHHW = Luminous range in nautical miles Colour of light is white unless otherwise stated NAVIGATION MARKS Lighthouse, major, minor light Beacon, port, starboard Safe water, isolated danger Spar buoy, port, starboard Pillar buoy, port, starboard Mooring buoy, yachting buoy Lead, front, rear Special Marks (yellow cross topmark) are not primarily to assist in navigation, but indicate special features. Y = Yellow Bu = Blue G = Green R = Red W = White 2 000 1 000 0 1 000 METRES 3 000 4 000 10 000 METRES 7 000 6 000 8 000 9 000 5 000 37 32 51 52 52 46 44 36 48 46 35 49 46 44 12 8 8 4 23 24 16 8 21 29 13 11 12 40 5 3 8 2 6 6 2 18 6 4 3 8 3 2 4 4 4 6 14 3 28 6 7 3 41 28 9 3 7 8 10 5 6 2 4 36 32 25 26 12 4 2 22 3 3 4 34 15 3 37 7 17 26 4 2 10 26 32 22 27 32 6 2 6 8 11 1 35 17 35 28 6 4 6 2 13 23 28 33 35 31 18 3 6 7 5 4 29 32 29 29 24 6 8 4 7 14 4 5 3 26 32 26 34 3 5 37 32 36 25 17 16 28 31 39 38 28 18 39 39 38 36 35 38 37 39 38 34 36 37 38 42 31 10 6 12 2 16 4 17 26 23 19 1 28 29 27 25 26 32 31 31 12 6 36 40 41 42 46 34 22 15 14 2 24 29 29 33 32 43 45 28 29 41 39 39 32 29 31 31 32 13 3 17 5 19 5 14 2 18 18 5 2 16 9 19 14 3 18 7 13 5 10 8 18 17 5 23 25 27 25 29 19 4 17 29 31 32 28 29 24 25 22 23 9 9 22 14 10 2 26 23 20 4 11 4 12 5 23 24 24 10 17 4 3 8 10 25 16 5 11 8 3 6 4 5 4 2 12 2 2 2 3 7 6 9 7 8 7 7 6 22 16 7 17 2 26 26 26 12 3 10 8 19 4 5 14 25 17 6 23 25 25 36 31 33 35 29 27 31 33 28 27 22 23 27 45 42 53 25 24 13 12 23 46 32 32 34 34 12 1 17 4 20 2 27 22 15 17 5 26 26 14 4 27 14 6 2 10 1 8 4 6 8 26 11 11 2 17 8 19 16 27 18 2 12 5 18 3 23 13 4 13 1 25 17 8 16 2 24 8 3 9 2 25 9 2 7 2 13 9 5 7 2 9 8 13 4 25 16 21 17 8 18 2 10 4 11 4 13 6 21 25 14 4 15 23 24 16 2 16 2 15 1 19 13 7 14 3 20 3 12 24 22 21 23 18 25 22 53 46 4 8 4 8 13 22 38 17 12 16 2 16 12 9 16 23 5 6 8 9 7 5 5 5 6 3 18 16 7 4 5 8 5 7 4 11 9 3 5 8 10 2 12 3 7 9 6 9 9 8 8 7 2 12 12 10 2 10 2 15 11 15 7 4 6 13 12 12 12 25 24 25 31 25 10 2 18 5 21 23 26 13 52 52 7 4 2 8 15 7 6 3 8 8 8 15 3 16 2 13 3 9 6 5 8 10 6 12 4 20 2 19 8 4 11 4 4 5 4 3 26 9 3 12 5 8 12 5 13 5 22 24 27 47 56 42 42 60 59 58 42 42 59 56 54 59 57 52 53 48 47 45 45 46 41 45 54 51 48 53 52 48 47 41 46 48 47 45 37 27 25 34 46 57 54 42 45 28 8 5 9 6 7 1 6 8 54 52 41 49 52 46 35 43 29 29 29 29 35 27 14 17 8 7 4 39 34 10 4 6 8 3 4 2 8 6 4 7 4 17 2 32 23 14 19 8 9 4 12 4 29 37 31 29 31 32 26 27 31 31 34 26 14 2 18 5 32 24 26 14 16 28 33 18 36 34 36 32 34 33 27 28 24 12 14 32 32 26 2 4 3 6 2 6 6 4 3 9 8 5 3 6 6 4 8 5 3 7 2 3 8 3 5 6 3 5 4 5 4 4 8 10 5 11 12 11 8 6 4 2 5 5 2 2 13 3 5 4 8 1 2 6 4 3 2 3 5 3 2 9 1 12 2 12 8 7 5 2 2 9 2 8 7 1 9 5 9 4 3 4 7 11 1 6 2 5 4 6 3 7 8 5 5 6 2 8 13 6 8 6 3 4 3 3 8 2 6 2 2 3 4 3 4 3 6 2 8 5 8 3 5 5 8 3 6 6 8 15 2 15 5 19 8 3 8 3 1 13 13 13 11 8 2 6 2 2 12 2 8 4 2 4 4 3 4 3 6 12 4 11 12 13 5 6 2 8 8 4 3 3 6 3 2 3 4 3 2 3 4 3 4 3 3 6 6 2 2 1 2 6 7 4 6 6 17 3 2 5 8 2 7 8 5 8 8 6 14 6 11 2 11 9 10 4 9 7 4 9 9 8 11 1 6 2 11 2 11 6 8 4 4 6 9 6 3 3 2 3 2 2 4 3 3 7 5 4 7 6 6 6 7 6 8 1 6 8 6 6 2 1 3 5 3 1 2 2 8 6 6 7 2 8 5 6 7 5 5 5 6 2 2 2 3 2 5 6 4 8 3 7 6 3 3 3 5 7 5 7 3 1 4 6 3 1 1 3 2 3 4 1 5 3 4 7 6 9 2 9 4 9 4 8 3 2 9 6 3 2 8 8 5 3 8 4 5 9 3 9 3 6 2 5 3 5 5 9 4 7 7 3 6 2 2 6 3 4 8 5 3 6 8 8 3 7 3 8 6 2 9 2 1 2 6 3 7 4 3 7 2 4 8 2 5 2 2 5 7 6 5 2 8 2 5 3 2 2 1 8 3 4 3 3 5 27 15 5 11 5 4 5 4 8 8 4 10 8 8 2 14 8 25 32 34 36 37 33 40 36 40 27 28 18 27 14 2 28 37 39 40 40 41 31 27 25 19 5 19 4 17 8 18 3 24 24 34 31 19 9 18 1 14 6 25 28 26 18 2 26 23 21 18 8 18 13 3 15 1 14 4 27 23 15 9 24 9 2 11 6 13 9 17 1 2 5 8 4 13 9 13 4 6 7 18 5 17 8 9 17 8 9 8 8 9 8 9 9 1 8 6 2 7 11 17 3 8 4 7 1 6 8 19 7 18 7 10 5 13 8 8 7 12 7 6 2 3 6 15 4 10 8 3 7 11 23 10 5 23 12 2 9 6 14 6 9 7 3 3 6 4 3 2 6 5 4 3 14 4 8 6 22 13 3 1 18 4 4 4 5 7 6 9 2 5 2 1 3 7 6 8 5 2 2 8 3 1 3 7 7 1 7 6 6 8 25 8 6 2 5 2 1 4 7 7 3 3 3 6 1 2 8 7 7 18 1 2 8 9 1 3 2 4 4 17 9 17 6 12 5 7 9 8 2 11 9 12 29 34 20 28 13 1 16 8 8 7 24 16 6 9 3 19 4 24 16 2 23 18 2 17 9 7 8 7 4 13 9 3 1 19 7 27 5 2 4 2 8 5 18 29 23 17 8 13 2 8 5 4 4 4 8 7 6 6 7 8 7 3 9 2 8 13 7 19 3 7 3 6 2 22 14 7 17 5 5 4 3 9 8 3 7 3 2 3 3 9 9 8 8 4 8 7 2 5 7 9 8 4 3 5 17 4 23 22 5 8 6 6 9 7 6 4 4 3 16 5 25 18 4 23 5 3 18 2 2 22 21 9 9 6 16 7 29 18 7 3 5 14 3 14 8 4 6 25 12 5 7 2 7 7 4 6 3 4 4 1 2 3 3 9 14 4 4 5 2 1 4 2 3 6 2 6 5 7 7 2 8 2 8 3 7 3 5 3 5 7 17 1 23 19 6 18 4 7 2 6 2 12 6 7 16 6 9 9 6 5 12 13 3 19 7 19 6 8 9 4 3 1 6 8 7 1 15 2 24 10 3 3 5 17 3 22 24 17 6 35 27 2 8 4 6 24 7 5 6 7 31 12 1 19 6 8 10 4 9 7 9 7 9 1 3 2 5 7 6 2 2 9 7 8 8 5 15 3 18 8 16 7 4 9 8 3 18 2 31 22 18 3 6 5 31 19 2 17 8 23 4 8 7 2 14 9 8 2 19 1 38 38 38 36 21 29 40 39 22 11 8 6 4 7 3 16 2 17 5 6 4 3 4 17 2 7 4 3 7 7 3 7 8 3 3 12 7 40 38 36 40 39 29 32 39 4 3 16 1 24 39 8 8 16 5 34 35 3 6 37 40 8 2 9 6 11 4 13 9 39 2 6 6 3 36 39 40 12 8 3 2 3 6 6 8 19 1 19 1 24 25 32 31 27 23 27 24 45 28 23 16 5 14 9 18 24 10 2 14 2 7 5 8 8 17 6 2 8 7 4 2 12 11 19 23 21 26 23 18 16 6 3 16 21 24 23 20 6 16 20 3 18 17 6 10 5 18 4 20 6 22 18 6 20 4 16 25 35 33 31 18 45 41 44 44 20 2 16 8 22 23 22 10 5 9 2 9 3 19 8 14 4 27 9 27 16 2 14 14 3 15 35 39 29 22 19 40 31 19 6 8 5 23 22 23 12 6 18 6 8 5 10 8 14 22 46 44 19 17 6 27 29 24 11 2 22 33 25 8 8 8 6 7 2 4 3 11 5 2 8 7 3 3 8 6 3 4 3 6 12 24 44 2 4 42 44 40 14 4 13 45 41 6 1 34 3 3 3 3 6 3 4 13 6 2 18 8 9 6 8 4 11 1 25 12 3 27 18 40 42 28 44 43 40 46 43 2 2 4 1 4 2 3 6 6 4 5 21 21 20 2 41 27 3 7 9 3 18 11 4 17 8 18 15 22 32 12 14 6 8 16 5 29 8 4 12 14 2 25 26 27 18 24 18 5 18 4 29 28 17 5 13 2 12 26 32 34 3 8 10 1 4 5 5 3 2 18 2 2 8 21 10 6 26 13 4 14 25 21 6 5 44 6 2 6 2 6 1 2 4 4 4 27 24 25 4 1 8 5 4 9 18 23 8 7 13 1 4 2 45 43 7 8 6 3 9 6 2 9 9 4 4 4 2 24 6 8 9 3 8 6 1 6 2 16 6 3 19 16 8 12 4 14 5 8 25 7 2 4 5 11 5 4 33 36 37 32 36 38 6 3 8 5 8 4 6 4 1 3 8 12 6 6 6 3 6 17 28 8 3 4 3 5 7 6 7 8 3 8 2 7 1 2 8 2 3 7 8 9 7 8 4 9 2 3 2 1 2 7 2 8 2 3 3 3 6 3 3 3 3 2 8 3 4 7 2 4 6 3 2 3 3 4 2 6 6 6 8 2 8 4 9 29 29 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 29 29 29 29 29 29 29 19 19 9 9 9 9 29 19 29 29 23 16 8 27 19 9 9 112 122 132 140 51 48 44 59 58 53 48 58 116 45 41 6 6 14 4 50 30 20 30 34 20 35 31 41 41 43 46 44 43 42 44 41 46 46 40 44 42 44 30 50 20 30 50 20 20 20 20 20 20 20 20 20 20 8 4 8 2 9 2 10 10 10 10 20 30 20 30 50 50 30 30 5 5 5 5 20 30 30 30 16 18 11 4 45 4 9 13 2 14 3 18 6 19 4 13 5 28 28 24 25 24 22 23 8 23 2 3 3 4 7 4 8 8 8 3 8 2 15 8 3 11 2 11 3 23 12 6 11 5 5 20 7 5 10 48 4 9 2 1 4 9 7 4 10 30 30 58 10 25 9 39 30 48 26 47 14’ 14’ 15’ 15’ 16’ 16’ 17’ 17’ 18’ 18’ 19’ 19’ 20’ 20’ 21’ 21’ 22’ 22’ 23’ 23’ 24’ 24’ 25’ 28° S 25' 28° S 26' 26' 27' 27' 28' 28' 29' 29' 30' 30' 31' 31' 32' 32' 33' 33' 34' 34' 34' 34' 35' 35' 36' 36' 37' 37' 38' 38' 39' 39' 40' 113° E 40' 113° E 41' 41' 42' 42' 43' 43' 44' 44' 45' 45' 46' 46' 47' 47' 48' 48' 49' 49' WA WA 999 999 METRES DEPTHS IN IN DEPTHS METRES 28° 34' 48" S 113° 33' 06" E 28° 13' 24" S 113° 49' 48" E HOUTMAN ABROLHOS - WALLABI GROUP HOUTMAN ABROLHOS - WALLABI GROUP AUSTRALIA - WEST COAST WESTERN AUSTRALIA DEPTHS HEIGHTS POSITIONS PROJECTION SOURCES NAVIGATION MARKS IALA Maritime Buoyage System - Region A (Red to Port). Heights are shown in metres. Underlined figures are drying heights above Sounding Datum. Overhead clearance heights are above Highest Astronomical Tide. All other heights are above Mean Higher High Water. Depths are shown in metres and decimetres, reduced to Sounding Datum, which is approximately lowest water level. Universal Transverse Mercator. CHART AMENDMENTS Positions on this chart are referenced to the Map Grid of Australia, Zone 50, based on the Geocentric Datum of Australia 1994 (GDA94). For GPS use, this approximates WGS84. TIDAL INFORMATION AND SOUNDING DATUM Place °S °E HAT MHHW MLHW MSL MHLW MLLW Heights in metres above datum Lattitude Longitude LAT The information provided on this chart is correct at time of publication. As this information is subject to change, ensure the latest version of the chart is used at all times and is kept up-to-date with reference to the following: xxx Notices to Mariners Changes of a safety or navigational nature will be reflected in Notices to Mariners. Current Notices are available from DoT chart sales offices, approved chart agents and at http://www.transport.wa.gov.au/imarine/coastaldata/. Navigable Waters Regulations Changes to Navigable Waters Regulations are published in the Western Australian Government Gazette. Regulations for Navigable Waters can also be found at http://www.slp.wa.gov.au/gazette/gazette.nsf. Marine Protected Areas Refer to Department of Fisheries and Department of Parks and Wildlife publications for the latest information. HOUTMAN ABROLHOS CHART LAYOUT Proposed Pelsaert Group WA 997 Side A 113° 33' 06" E 28° 34' 48" S 28° 13' 24" S 113° 49' 48" E A1 A2 B C D U 20m 50m 500m Worse than ZOC C ZOC Seafloor Coverage Position Accuracy ZOC CATEGORIES (For details see Australian Seafarers Handbook AHP 20) All significant seafloor features detected. All significant seafloor features detected. Depth anomalies may be expected. Large depth anomalies may be expected. Unassessed - The quality of the bathymetric data has yet to be assessed. Uncharted features hazardous to surface navigation are not expected but may exist. Zone of Confidence (ZOC) Diagram = 0 50m + 1%d = 1 00m + 2%d = 1 00m + 2%d = 2 00m + 5%d 5m Depth (d) Accuracy HOUTMAN ABROLHOS WALLABI GROUP SCALE 1 : 50 000 Rat Island 28°43' 113°47' 1.31 0.93 0.73 0.68 0.60 0.46 0.10 Geraldton 28°47' 114°35' 1.36 1.00 0.78 0.75 0.66 0.51 0.15 From the latest information available to Department of Transport, 2016. Dick Island West Wallabi Island Pigeon Island East Wallabi Island WARNING During moderate to heavy seas, South Passage may close off and become unsafe for navigation. Know you boat Safety equipment BOATING SAFETY INDIAN North East Reef Beacon Island Fl 5s 7m 10M Eastern Island Long Island Dick Island Q(3) 10s 6m 5M West Wallabi Island Acute Bank Assail Bank FISH POINT Fl R 3s 6m 5M Pigeon Island Fl(3) 30s 18m 15M Latitude Hill Record Hill Beagle Knoll The Flat The Big Breaker East Wallabi Island Reef Evening Reef Observation Area Reef Observation Area See Enlargement on Reverse Side Reef Observation Area WARNING During moderate to heavy seas, South Passage may close off and become unsafe for navigation. North Island Airstrip OCEAN See DoT Chart WA 998 Q 5M Q 6M Wallabi Group WA 999 Side A Easter Group WA 998 Side A B C C Reef navigation Know the weather Inform others THE HOUTMAN ABROLHOS CODE OF CONDUCT MOORINGS SHIPWRECKS REEF OBSERVATION AREAS 113° 40' E 28° 30' S 113° 40' E 28° 30' S 2 000 1 000 0 1 000 METRES 3 000 4 000 10 000 METRES 7 000 6 000 8 000 9 000 5 000 28° 13' 24" S 113° 49' 48" E 28° 34' 48" S 113° 33' 06" E Notices to Mariners inclusive 1 - April 2018