Australia State of the Environment Report 2001 (Theme Report)
Australian State of the Environment Committee, Authors
Published by CSIRO on behalf of the Department of the Environment and Heritage, 2001
ISBN 0 643 06751 5
Environmental indicators reported in this section:
|CO 7.14||Ship visits|
|CO 7.15||Shipping accidents|
Shipping and impacts [CO Indicator 7.14]
Commercial shipping and port activity are vital and legitimate uses of our seas and coast, but they present environmental costs and risks. The main shipping lane around the world is from Europe to Asia, with Singapore being the hub port in South East Asia. Shipping to and from Australia is a sublink into the main shipping lane. There are some 11 000 vessels from 600 overseas ports that visit Australia's 65 ports, and a coastal trade distributing goods to the other ports. As the countries with whom Australia trades change, constant vigilance is needed to reduce the chances of introduced species establishing in our tropical and temperate waters.
The main environmental issues associated with shipping and ports include:
- effects of dredging channels and disposal of the dredged material,
- effects of antifouling paints in ports and off-shore,
- risk of introduction of exotic species into ports, harbours and coastal waters
(see Ship wastes in port),
- ship waste in ports,
- risk of oil or hazardous cargo spills in ports and coastal waters,
- reclamation of intertidal habitats, and
- loss of public access.
Figure 27: First port of call of international shipping into Australia.
Source: Environment Australia (2000)
Dredging within ports is generally undertaken for two reasons. New berths or deeper shipping channels are needed to accommodate an expansion of the port or access by larger vessels (capital dredging), or there is a loss of pre-existing depths due to a buildup of sediment (maintenance dredging). The latter can be an ongoing issue for some port companies. Channel dredging in gulfs and bays for navigation and safety reasons may also be required.
The nature and quality of the marine and estuarine sediments can vary greatly around Australia, ranging from uncontaminated sands, which are generally suitable for sea disposal, to contaminated (with heavy metals, pesticides etc.) clays and fines that require a careful environmental impact assessment of disposal options. As many Australian ports are located in relatively muddy environments, substantial short-term turbidity can result from dredging activities.
Under the Environment Protection (Sea Dumping) Act 1981 (the Sea Dumping Act), a permit is required to authorise the loading for the purposes of dumping, and the dumping at sea, of wastes and other matter.
In this context, the effects of dredging and associated dumping have been widely studied in a number of Australian ports. In December 1998 the ANZECC Interim Ocean Disposal Guidelines were released for a two-year trial period. These guidelines were designed to assist applicants to assess environmental impacts from sea dumping of dredged and excavated material, in accordance with the Convention on the Prevention of Marine Pollution by the Dumping of Wastes and Other Matter 1972 (the 'London Convention'), and the 1996 Protocol to that Convention. The review of these guidelines, which is currently under way, is likely to be completed in late 2001.
Amendments to the Sea Dumping Act, to reflect the Protocol, commenced to have effect on 16 August 2000. On 4 December 2000, Australia formally ratified the Protocol.
Another significant environmental issue is the use of organotins such as tributyl tin (TBT) as biocides in antifouling paints used on vessels to prevent the buildup of organisms on ship's hulls. Its use has been of critical importance to efficient commerce and to impeding the spread of marine pests, parasites and diseases into ports, harbours and coastal waters.
There is international pressure to phase out TBT-based antifouling paints because of its extreme toxicity to marine life and its persistence in the environment (see toxicants).
The grounding of a Malaysian container ship on Sudbury Reef in the Great Barrier Reef Marine Park in late 2000 resulted in levels of TBT on the Reef that were 100 times the safe level. In the largest cleanup operation of its kind in the world, divers removed flakes of antifouling paint from a 1500 square metre section of the Reef in January 2001.
The International Maritime Organisation (IMO) is finalising an international convention that would ban the use of organotins in antifouling systems. Under Australia's Oceans Policy, the Commonwealth Government is committed to banning the use of TBT from 1 January 2006 on vessels being repainted in Australian docks unless the IMO sets an earlier date for such a ban.
A long-term project conducting trials of new antifouling paints commenced in Australia in 2000. The project is a cooperative effort between the maritime, paint and coatings industries, the Royal Australia Navy, the Defence Science and Technology Organisation and Environment Australia.
The shipping industry includes shipbuilding and the repair and maintenance of vessels, which are carried out at several ports around Australia. In the course of normal operations there is a risk of spills of oil, wastes from vessel maintenance, bilge water and sewage, and these could affect port water quality. Recreational vessels can also contribute wastes to the marine environment.
There are a number of measures in place, to both systemically and practically minimise this pollution. On a systemic level, discharges from ships are subject to the various Annexes of the international MARPOL Convention, which is implemented through Commonwealth, State and Territory legislation. Up to the present time, Australia has adopted Annexes I (oil), II (noxious liquid substances), III (packaged harmful substances) and V (air pollution). Annex IV (sewage) has not yet been adopted by Australia and consequently the control of sewage discharges from ships is inconsistent between States.
On a practical level, 35 demonstration projects are under way around Australia to build facilities to capture and treat wastes from marinas (as at May 2001). Funds are being provided by industry and port authorities, matched by Commonwealth funds from the Coasts and Clean Seas Initiative.
Oil and hazardous cargo spills [CO Indicator 7.15]
Oil and hazardous cargo spills can occur either in ports and harbours or in offshore waters. Spills can happen as a result of accidents, such as collisions or groundings on off-shore reefs. Their environmental impacts depend on the nature and quantity of oil spilt and the habitat and species that are affected.
In 1998 the Australian Maritime Safety Authority (AMSA) was funded, through the Coasts and Cleans Seas Initiative, to fast-track the production of a computerised Oil Spill Response Atlas for Australia. The major outcome is an Oil Spill Response Atlas for Australia in a computerised geographic information system (GIS). This will enable a more targeted response to oil spills in future by identifying marine and coastal areas of sensitivity that could be affected in the event of an incident.
AMSA also keeps a database of oil spills and since 1995 Australia has not experienced an oil spill with major environmental impacts. Significant spill incidents that have occurred since 1995 are given in Table 8.
|Date||Situation||Location||Quantity and type||Environmental effects|
|April 1996||Collision between tanker and tug||Brisbane River||Heavy fuel oil
Approx 15 tonnes
|Cleanup of foreshore and sensitive areas required|
|August 1998||Tanker at berth||Brisbane River||Lube oil
|Several foreshore areas required remediation|
|June 1999||Offshore loading||2 nm offshore Port Stanvic Refinery, SA||Oman crude
Approx. 230 tonnes
|Light impact at shoreline|
|August 1999||Cargo transfer||Sydney Harbour||Light crude
|Light to medium oiling of some foreshores|
Sources: AMSA annual reports.
AMSA has, since 1973, had in place a national strategy for responding to marine spills. The original oil spill strategy was extended in 1998 to deal with the response to maritime chemical spills in Australian waters and is now known as the National Plan to Combat Pollution of the Sea by Oil and other Noxious and Hazardous Substances. The responsibility for implementing this plan is shared among the Commonwealth, States and the Northern Territory and the oil and shipping industries.