Assessment of the Maintenance Dredging Strategy's effectiveness

Maintenance Dredging Strategy Principle 1

Great Barrier Reef World Heritage Area ports will develop Long-term Maintenance Dredging Management Plans consistent with the framework outlined in this document that: contribute to maintaining and enhancing the outstanding universal value of the Great Barrier Reef are based on the best available science utilise the principles of ecologically sustainable development ensure continued efficient operation of the port are developed in consultation with key stakeholders. Great Barrier Reef World Heritage Area ports will publish their Long-term Maintenance Dredging Management Plans.

Maintenance Dredging Strategy Action 1

Great Barrier Reef World Heritage Area Ports will work with the Department of Transport and Main Roads, regulators and relevant stakeholders to develop guidelines for Long-term Maintenance Dredging Management Plans in accordance with the Long-term Maintenance Dredging Management Framework outlined in the Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports. Development of the Long-term Maintenance Dredging Management Plans guidelines is intended to be completed by June 2017. Development of Long-term Maintenance Dredging Management Plans will commence concurrently, with priority to be given to Great Barrier Reef World Heritage Area ports that dredge annually or frequently.

The Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports (the Strategy) required all Great Barrier Reef World Heritage Area ports to develop Long-term Maintenance Dredging Management Plans to:

• assist in the consistent application of assessment, planning and monitoring of maintenance dredging activities
• establish a whole-of-system understanding that improves the certainty of environmental outcomes and stakeholder confidence
• address the operational needs, environmental risks, monitoring and adaptive actions of maintenance dredging in ports.

To provide ports and regulators with guidance on implementing the framework, the Department of Transport and Main Roads published the Guidelines for Long-term Maintenance Dredging Management Plans in June 2018 (the Guidelines). The Guidelines ensure a consistent, transparent, and accountable process is applied. The Guidelines outline the Queensland Government’s expectation with respect to continued improvement in maintenance dredging management and achieve the following key outcomes:

• to have a consistent application of assessment, planning and monitoring tools over time to assist in establishing a whole-of-system understanding and confidence in the management of maintenance dredging
• to improve certainty of environmental outcomes and stakeholder confidence
• to set out expectations on how these will be achieved in a more transparent and consultative process.

The Guidelines are used in preparing a Long-term Maintenance Dredging Management Plans for Great Barrier Reef World Heritage Area ports.

By 31 December 2018 all Great Barrier Reef World Heritage Area ports developed port specific Long-term Maintenance Dredging Management Plans in a transparent manner aimed at creating a framework for continual improvement in environmental performance. These are published on the relevant port authority's website. The Long-term Maintenance Dredging Management Plans sit within a broader framework of documents that each port uses to manage the environmental impacts from dredging.

An assessment of each of the initial Long-term Maintenance Dredging Management Plans for Great Barrier Reef World Heritage Area ports confirmed the structure and approach aligned with the Guidelines. Ongoing, the onus lies with ports to self-manage their auditing and review processes as they do with all their management systems, including environmental management systems.

Although Long-term Maintenance Dredging Management Plans are not a statutory component of the port regulatory framework, regulatory assessors have used Long-term Maintenance Dredging Management Plans as supporting evidence when assessing and conditioning approvals. Long-term Maintenance Dredging Management Plans have also been developed for several non-Great Barrier Reef World Heritage Area ports in Queensland to support permit applications.

Finding: Principle 1 is being applied and Action 1 is complete. The guidelines for Long-term Maintenance Dredging Management Plans were published in June 2018, with development of Long-term Maintenance Dredging Management Plans concurrently undertaken. All Great Barrier Reef World Heritage Area ports developed port-specific Long-term Maintenance Dredging Management Plans by 31 December 2018. All Long-term Maintenance Dredging Management Plans are published on the relevant port authority’s website:

• Far North Queensland Ports Corporation Limited (trading as Ports North) Long-term Maintenance Dredging Management Plans for the ports of Cairns, Cape Flattery, Cooktown, Mourilyan and Quintell Beach
• Port of Townsville Limited Long-term Maintenance Dredging Management Plans for the ports of Lucinda and Townsville
• North Queensland Bulk Ports Corporation Limited Long-term Maintenance Dredging Management Plans for the ports of Abbot Point, Hay Point and Mackay
• Gladstone Ports Corporation Limited for the ports of Rockhampton and Gladstone.

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Maintenance Dredging Strategy Principle 2
Long-term Maintenance Dredging Management Plans for Great Barrier Reef World Heritage Area ports will be based on an understanding, using the best science available, of sediment transport processes and environmental values relevant to maintenance dredging activities.

Maintenance Dredging Strategy Action 2

Ports will lead implementation of Reef Action Water Quality Action 17, working with relevant government agencies and the scientific community to understand the port sediment characteristics and risks at the four major ports and how they interact and contribute to broader catchment contributions with the Great Barrier Reef World Heritage Area. The project will be completed by the end of December 2017.

In line with the Reef 2050 Long-Term Sustainability Plan (Reef 2050 Plan), the Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports (the Strategy) recognises the best available science and knowledge is required to manage the impacts of maintenance dredging on the Reef, to protect its values, reduce threats and improve its current and long-term outlook. It also recognises that ongoing research and innovation is critical to finding the best approaches to manage impacts.

The Strategy outlines the first phase of the long-term maintenance dredging management framework involves gathering relevant information on which to develop and subsequently assess sediment management needs and options. Relevant information includes:

• detail on sediment regimes
• determining the impacts of sediment on port operations
• evaluating whether there is a need to manage sediment
• assessing the social and environmental values within and surrounding the port.

The Strategy requires that Great Barrier Reef World Heritage Area ports undertake assessments to understand:

• the port sediment characteristics, including:
• defining the nature and sources of marine sediments that accumulate in the navigational areas of the port
• describing the forces that drive sediment dynamics at the local, regional and wider Great Barrier Reef lagoon scale
• the environmental, social and cultural values of the relevant port and the surrounding areas.

The Department of Transport and Main Roads funded the development of a Technical Support Document to provide a scientific and technical evidence basis for the guiding principles and actions outlined in the Strategy.

Water Quality Action 17 required an assessment of port sediment characteristics and risks at the four major ports and how they interact and contribute to broader catchment contributions within the Great Barrier Reef World Heritage Area. To meet Action 2 of the Strategy, and as part of Water Quality Action 17 of the Reef 2050 Plan, Queensland Ports Association undertook a study to understand the port sediment characteristics and risks.

The study assessed sediment at the ports of Gladstone, Hay Point, Mackay, Abbot Point, Townsville, and Cairns, and how this interacts and contributes to broader catchments within the Great Barrier Reef World Heritage Area. It includes an executive summary report, titled Sediments and Dredging at Great Barrier Reef Ports. These port-scale assessments have been further aggregated into an overall sediment budget for the inner-shelf region of the entire Great Barrier Reef.

This was supported by a technical report prepared by consultant BMT WBM Pty Ltd titled Great Barrier Reef Quantitative Sediment Budget Assessment related to maintenance dredging at the ports of Gladstone, Hay Point, Mackay, Abbot Point, Townsville, and Cairns. This work was scoped in 2017 with input from research agencies and has been reviewed by environment managers from each port authority, Queensland Ports Association and technical specialists engaged by the ports. The Great Barrier Reef Quantitative Sediment Budget Assessment has also been the subject of an independent peer review by Dr Andy Symonds from Port and Coastal Solutions.

Water Quality Action 17 compliments the local scale studies being undertaken by individual port authorities, including sustainable sediment projects and increased monitoring to develop the knowledge base for maintenance dredging activities. Great Barrier Reef World Heritage Area ports have captured and communicated supporting studies, and science that underpins the Long-term Maintenance Dredging Management Plans and in many cases data is publicly available.

Long-term Maintenance Dredging Management Plans have been prepared for all ports within the Great Barrier Reef World Heritage Area although some of these ports do not undertake maintenance dredging, or in some cases are not commercial ports. One stakeholder queried the utility of Long-term Maintenance Dredging Management Plans for ports that do not undertake maintenance dredging. Long-term Maintenance Dredging Management Plans are important to developing the knowledge base for sediment characteristics and processes across the whole Great Barrier Reef World Heritage Area catchment. Long-term Maintenance Dredging Management Plans can be used to inform proposed projects and future management regimes, even if maintenance dredging is not currently required.

Where regular maintenance dredging is undertaken at Great Barrier Reef World Heritage Area ports, the managing port authority conducts a range of sustainable sediment management research projects to inform the development of the Long-term Maintenance Dredging Management Plans. These research projects have been undertaken at the ports of Cairns, Townsville, Mackay, Hay Point, Rockhampton, and Gladstone. Examples of considerations as part of the sustainable sediment management research projects include:

• feasibility of avoiding or reducing maintenance dredging
• investigating beneficial reuse opportunities and other alternatives
• comparing placement alternatives based on potential impacts to environmental, health and safety, social and economic values.

An assessment of all Long-term Maintenance Dredging Management Plans for Great Barrier Reef World Heritage Area ports found that all port authorities incorporate the information gathered from relevant studies, monitoring programs and consultation into their Long-term Maintenance Dredging Management Plans. The Long-term Maintenance Dredging Management Plans outline sediment regimes within the ports, as well as the environmental, social, and cultural values which need to be considered.

In accordance with the Guidelines for Long-term Maintenance Dredging Management Plans, all Great Barrier Reef World Heritage Area ports describe the process and studies that have (or will) be undertaken to understand sediment dynamics, characteristics, and sedimentation rates at Great Barrier Reef World Heritage Area ports that can be used to forecast dredging requirements.

In addition, Great Barrier Reef World Heritage Area ports synthesise existing studies to establish what environmental values are important to manage during maintenance dredging activities and identify actions to maintain knowledge of environmental values.

The following case study of the Port of Hay Point Sustainable Sediment Management Project demonstrates how Great Barrier Reef World Heritage Area ports examine how and why sediment accumulates. This understanding assisted in exploring ways to reduce sediment build-up in navigational areas, to reduce the need to undertake maintenance dredging, as well as develop and subsequently assess sediment management needs and options when maintenance dredging cannot be avoided. All Great Barrier Reef World Heritage Area ports apply similar processes, as outlined in their Long-term Maintenance Dredging Management Plans, to develop a knowledge base, using the best science available, for their maintenance dredging activities.

Case Study: Port of Hay Point Sustainable Sediment Management Project

From 2015–2017, NQBP undertook an extensive research project to investigate the most sustainable way to manage accumulated sediment in and around the Port of Hay Point: Port of Hay Point Sustainable Sediment Management Assessment for Navigational Maintenance. The Sustainable Sediment Management project investigated where specifically the sediment at the Port of Hay Point comes from, what impact it has on port operations, whether accumulation can be eliminated or reduced, and what alternatives are available to reuse or manage of any sediment that might need to be dredged. The project determined the best short and long-term approach to managing sediments within the port. This included investigation and consideration of: the source and nature of the sediment at the port the requirements for management of the sediment in the short and longer term whether sediment can be managed without dredging while maintaining port operations and meeting legal requirements the feasible alternatives for use or placement of material if dredging is required the best package of measures to provide for long-term (25-year) sustainable management of marine sediments at the port. The Sustainable Sediment Management project involved consultation with stakeholders including federal, state and local government; port operators; conservation groups; the local community including Traditional Owners, fishing groups and community bodies; researchers; and tourism operators.

Finding: Principle 2 is being applied and Action 2 is complete. The Queensland Ports Association engaged BMT WBM to prepare a Quantitative Sediment Budget Assessment of the entire Great Barrier Reef and regions surrounding the Great Barrier Reef World Heritage Area ports which was the subject of an independent peer review. The assessment compliments the local scale sustainable sediment studies being undertaken by individual port authorities. Ports have undertaken studies and increased monitoring to develop the knowledge base for maintenance dredging activities.

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Maintenance Dredging Strategy Principle 3
Great Barrier Reef World Heritage Area ports will include future maintenance dredging requirements in port infrastructure planning to ensure relevant environmental values and potential impacts are properly understood, and to assist in minimising the need for maintenance dredging.

The Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports (the Strategy) requires Great Barrier Reef World Heritage Area ports to examine feasible opportunities to avoid or reduce sedimentation in port areas, with consideration of:

• port infrastructure planning
• realities of volume limits
• the source and quantity of sediments
• port location (river, estuary, open water)
• channel redesign and alternatives to dredging
• additional port infrastructure.

Maintenance dredging poses a significant cost and port authorities aim to reduce maintenance dredging requirements as much as possible and will only undertake dredging when necessary. Some of the measures that Great Barrier Reef World Heritage Area ports have been implementing to reduce the volume of material that needs to be managed include:

• undertaking regular hydrographic surveys to provide a high degree of certainty for siltation – this allows ports to focus on particular areas for dredging, minimises dredge volumes and reduces dredge campaign lengths
• bed levelling to level out high points in a channel and help to reduce the frequency of maintenance dredging, and/or improve the efficacy of dredging equipment
• periodic drag barring and sea raking techniques to reduce maintenance dredging in berth areas
• use of siltation trenches to capture fine sediment and reduce the frequency of maintenance dredging as well as other forms of in-channel placement
• in consultation with Maritime Safety Queensland, a branch of the Department of Transport and Main Roads, using shipping simulations to fine tune the specification of vessels and sailing conditions to resolve the parameters within which certain vessels can utilise a channel and facilities of set dimensions, which may reduce the need for maintenance dredging frequency or volumes
• making use of tidal windows by maximising vessel movements through shallower areas during higher stages of the tide to ensure sufficient under keel clearance (it should be noted that this approach can result in operational inefficiencies and has the potential to result in safety and environmental implications if not managed correctly)
• potential minor modification of channels if it may result in reduced sedimentation
• working with port tenants and customers to manage their infrastructure and operations to minimise the requirement for maintenance dredging
• consideration of future maintenance dredging requirements as part of early infrastructure planning.

In accordance with the Guidelines for Long-term Maintenance Dredging Management Plans, all Great Barrier Reef World Heritage Area ports provide details in their Long-term Maintenance Dredging Management Plans on any examinations undertaken to reduce the rates of sedimentation in port navigational areas that could avoid or reduce the need to dredge.

Case Study: Port of Gladstone Reduce Assessment

As part of Gladstone Ports Corporation Sustainable Sediment Management Project, a key report was the ‘Reduce Assessment’. For this study it was important to acknowledge that sediment from maintenance dredging is an essential component of natural sediment budgets and ecosystems. A key principle therefore was to consider dredged material as a valuable resource to be used in the natural environment, rather than a waste material for disposal. Reduce dredging approaches were based on three broad strategies—keep sediment out, keep sediment moving, and keep sediment navigable. A total of 11 possible ‘reduce’ approaches were identified based on information taken from global best practice guidance. Of these, seven approaches were considered potentially feasible based on the natural processes driving sedimentation in the Port of Gladstone. From a detailed objectives assessment, four possible approaches were selected as ones needing further evaluation: sustainable in-channel placement for Jacob’s Channel (currently being trialled) sustainable in-channel placement for the Marina jet arrays for berth pockets in Jacob’s Channel nautical depth navigation and drag barring for berth pockets in Jacob’s Channel.

Finding: Principle 3 is being applied. Port infrastructure planning includes assessment of future maintenance dredging requirements, and all ports examine opportunities to reduce rates of sedimentation within port infrastructure.

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Maintenance Dredging Strategy Principle 4
Maintenance dredging will be limited to that required to maintain the approved dimensions of port infrastructure to ensure efficient shipping access and the optimisation of port operations (that is, will not be used to increase channel or berth footprints or depth).

Maintenance Dredging Strategy Principle 5
An increase in channel or berth dredging areas and depths will only occur as a result of approved capital dredging following assessment of implications of future maintenance dredging needs and disposal options (as per existing approval processes).

The Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports (the Strategy) requires that Great Barrier Reef World Heritage Area ports try to minimise the actual volume of dredging required and reduce the frequency of dredging activities to only those that are critical to the ongoing and efficient operation of the port.

The Strategy does not seek for the adoption of an annual maintenance dredging volume limit given maintenance dredging requirements are primarily controlled by natural sediment processes. However, the Strategy sets an expectation that ports will try to minimise the actual volume of dredging required, and reduce the frequency of dredging activities to only those critical to the ongoing and efficient operation of the port. Some of the measures Great Barrier Reef World Heritage Area ports have been implementing to reduce the volume of material that needs to be managed include:

• undertake maintenance dredging only to return the channels, aprons and berths to design depths
• use pre and post maintenance dredging surveys to demonstrate that dredge depths have not been exceeded, within an agreed dredging tolerance
• ongoing surveys to ensure sedimentation processes are well understood, maintenance dredging is focussed on where sedimentation has occurred, and maintenance dredging is only undertaken where required.

The Sustainable Ports Development Act 2015 (Ports Act) prohibits major capital dredging for the development of new or expansion of existing port facilities in the Great Barrier Reef World Heritage Area outside the priority ports of Gladstone, Townsville, Hay Point/Mackay and Abbot Point, as well as the sea-based placement of port-related capital dredged material within the Great Barrier Reef World Heritage Area. The Ports Act includes specific provisions (section 35(2)(b) and (3)) that allows the carrying out of limited capital dredging for a port facility within the inner harbour of the Port of Cairns. Up to 50,000 cubic metres of material can be approved to a limit of no more than 150,000 cubic metres of material in a four-year period.

The Strategy requires that any further approvals for capital dredging includes an assessment of future maintenance dredging needs and placement options. Since the introduction of the Strategy, capital dredging projects at Great Barrier Reef World Heritage Area priority ports and the Port of Cairns have been undertaken, are underway, or have received environmental approvals. These proposals included assessments of future maintenance dredging needs including:

• ongoing dredging requirements and potential placement options
• infrastructure design options
• opportunities to avoid or minimise future maintenance dredging requirements.

Since 2017 annual maintenance dredging has occurred at the ports of Cairns, Townsville, and Gladstone. Maintenance dredging was conducted once in the Port of Abbot Point in 2017, Port of Hay Point in 2019, and Port of Mackay in 2020.

A review of the maintenance dredging reports provided annually by the Queensland Ports Association to the Department of Transport and Main Roads, as well as reports provided to the various Technical Advisory and Consultative Committees by port authorities, indicates that Great Barrier Reef World Heritage Area ports have not undertaken any maintenance dredging which has exceeded the approved dimensions of port infrastructure.

Port	2017	2018	2019	2020	2021	2022	2023
Quintell Beach	0	0	0	0	0	0	0
Cape Flattery	0	0	0	0	0	0	0
Cooktown	0	0	0	0	0	0	0
Cairns	386,809	517,747	319,959	179,380	460,265	535,234	336,173
Mourilyan	0	0	0	0	0	0	0
Lucinda	0	0	0	0	0	0	0
Townsville	629,140	378,395	999,382	501,016	269,236	398,050	333,499
Abbot Point	9,700	0	0	0	0	0	0
Mackay	0	0	0	123,870	0	0	0
Hay Point	0	0	353,740	0	0	0	0
Rockhampton	0	0	0	0	0	0	0
Gladstone	209,456	241,682	231,855	442,041	239,228	211,726	276,872

 

Finding: Principles 4 and 5 are being applied. All maintenance dredging undertaken has been limited to approved dimensions only. Capital dredging projects approved in the last 5 years have included assessments of future maintenance dredging needs and placement options.

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Maintenance Dredging Strategy Principle 6

Great Barrier Reef World Heritage Area ports will: ensure that Long-term Maintenance Dredging Management Plans include an assessment of beneficial reuse options for dredged material management to determine if viable opportunities exist seek to beneficially reuse material where viable options are available, in accordance with existing regulatory requirements and the comparative analysis outlined in this document continue to assess the latest scientific, technological and other factors which may render previously unsuitable practices suitable or viable for beneficial reuse work with relevant Queensland and Australian government agencies and scientific organisations to conduct an examination and, where appropriate, a pilot program to evaluate different treatment and reuse options for managing dredged material consistent with the requirements of the Reef 2050 Long-Term Sustainability Plan Water Quality Action 15.

Dredging and dredged material placement is subject to comprehensive assessment processes at both state and federal levels. These processes require ports to provide information on potential impacts and proposed management, following the avoid, minimise, mitigate, offset hierarchy. This may include, for example, assessment against the codes for coastal development and tidal works and removal, destruction or damage of marine plants in the Queensland Government’s State Development Assessment Provisions.

The state and federal regulatory framework, in conjunction with the National Assessment Guidelines for Dredging 2009, requires beneficial reuse and on-land placement be considered prior to at-sea placement of dredged material. Approval requirements will vary depending on the extent and location of the activity, but could include assessment under:

• Queensland legislation such as the Coastal Protection and Management Act 1995, Environmental Protection Act 1994, Fisheries Act 1994, Forestry Act 1959, Marine Parks Act 2004, and/or Planning Act 2016
• Australian legislation such as the Environment Protection and Biodiversity Conservation Act 1999, Environment Protection (Sea Dumping) Act 1981 and/or Great Barrier Reef Marine Park Act 1975.

In addition to the regulatory framework, and in response to Water Quality Action 15 from the original Reef 2050 Long-Term Sustainability Plan (Reef 2050 Plan), Ports Australia published the Environmental Code of Practice for Dredging and Dredged Material Management in 2016 which establishes environmental principles for dredging and reusing, relocating, or placement of dredged material.

Water Quality Action 15 also required development and implementation of a dredging management strategy that includes an examination and, where appropriate, a potential pilot program to evaluate different treatment and re-use options for managing dredged material, and measures to address dredging-related impacts on Reef water quality and ecosystem health.

Some stakeholders expressed concern that dredged material from maintenance dredging continued to be placed at sea within the Great Barrier Reef World Heritage Area and that this placement option did not ensure the ongoing protection of the Great Barrier Reef’s outstanding universal value. Conversely, other stakeholders expressed concern that following initial beneficial reuse assessments, onshore placement of dredged material was often chosen without investigating alternative reuse options or at sea placement options that may have a lesser environmental impact.

Consistent with the regulatory framework, Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports (the Strategy) notes there are several technical, social, and environmental constraints for beneficial reuse and land placement options for dredged material in Great Barrier Reef World Heritage Area ports. The Strategy also notes, it is important that beneficial opportunities at each port are continually assessed. If beneficial reuse of all or part of maintenance dredged material is not feasible, options to place dredged material onshore or at sea will need to consider impacts other than those associated with the actual dredging activity. This may include, for example, potential impacts associated with acid sulphate soils, the alteration of coastal processes, or loss of wetland/tidal habitat.

The existence of potentially suitable options does not necessarily imply they are viable options, as detailed site-specific assessment of technical, economic or environmental factors may limit their feasibility at a particular port. The Strategy notes that removing sediment to land may not always be the preferred option, with the Technical Supporting Document referencing international and Australian examples which indicate that in many instances, maintaining the material within the coastal system can be the most appropriate management option.

In Queensland, placement of maintenance dredged material at sea at designated offshore sites can often represent a lower overall environmental impact compared to placement and the long-term management of land-based sites. Potential factors that may influence the suitability of placement options include volume of material, quality of sediments and presence of contaminants and engineering qualities. Therefore, the Strategy needs to retain some flexibility on the most suitable option for maintenance dredged material, consistent with the requirements of the existing regulatory framework.

The Strategy requires continual review processes for beneficial reuse options be incorporated into the Long-term Maintenance Dredging Management Plans for Great Barrier Reef World Heritage Area ports. In accordance with the Guidelines for Long-term Maintenance Dredging Management Plans, all Great Barrier Reef World Heritage Area ports provide publicly available information in their Long-term Maintenance Dredging Management Plans regarding options investigations. This includes assessment of feasible sediment management options for use or placement of material if dredging cannot be avoided. This information is typically provided under an 'Examination of reuse, recycle and placement options' section of the Long-term Maintenance Dredging Management Plans and is used to support applications to place dredged material at sea.

Investigation of dredged material management options at Great Barrier Reef World Heritage Area ports typically involves a comprehensive reuse assessment investigation. Factors considered include sediment suitability, greenhouse gas emissions, opportunity or demand, conceptual cost, confidence in beneficial reuse process, duration from construction to use, environmental implications, socio-economic implications, environmental approvals, constraints, knowledge gaps and longevity of the beneficial reuse option. Each of the Long-term Maintenance Dredging Management Plans have reflected the findings of the Strategy that there are several technical, social, and environmental constraints for beneficial reuse and land-based placement options for maintenance dredged material in Great Barrier Reef World Heritage Area ports. This is particularly relevant for ports that must deal with a large volume of material that is of poor-quality for engineering purposes. However, it remains important that beneficial reuse opportunities at each port are continually assessed to ensure that new technologies and beneficial reuse opportunities are identified and considered. This includes the review of approaches and guidelines on beneficial reuse being developed overseas by international associations such as PIANC, the World Association for Waterborne Transport Infrastructure, to ensure that best practice initiatives developed by Queensland and Australian ports are recognised and embedded in global guidelines, for example: Beneficial Use for Sustainable Waterborne Transport Infrastructure Projects.

Some specific examples where current practices, trials and future planning are being explored for beneficial reuse of maintenance dredged material include:

• Port of Abbot Point – due to the clean sandy nature of the material accumulating in the Material Offloading Facility area (deposited from long-shore coastal drift), previous dredging actions in this area have used the maintenance dredged material for beach replenishment to the north of the Marine Offloading Facility
• Port of Townsville – over recent years, particularly since the 2019 floods, the port has been providing sand that has been dredged from Ross River to the local authority for beach re-nourishment at Rowes Bay beach to address erosion issues
• Port of Townsville – research trials are underway to beneficially reuse saline dredged material mixed with terrestrial organic waste and treated with organic mixing agents to determine suitability of use outside saline environments
• Port of Gladstone – initial trials for sediment reduction and beneficial re-use, as part of the Sustainable Sediment Management studies, are underway.

While stakeholders provided positive feedback about increased transparency because of the Strategy, some stakeholders sought more transparency about the decision-making process to decide on the preferred placement option. Similarly, although feedback on the function of Technical Advisory and Consultative Committees was supportive, some stakeholders encouraged a wider stakeholder group be consulted and invited to join relevant committees.

The Strategy acknowledges that one of the key principles of decision-making outlined in the Reef 2050 Plan is to adopt a partnership approach to management of the Great Barrier Reef World Heritage Area. Under this approach, governance arrangements are to be transparent and accountable. Further, communication and transparency are key components of best practice risk management systems, and mechanisms to ensure transparency around monitoring and reporting need to be part of the management process.

To build on this partnership approach and respond to stakeholder feedback, it is recommended that the Technical Advisory and Consultative Committees membership and communications plans be regularly reviewed by Great Barrier Reef World Heritage Area ports.

Finding: Principles 6 is being applied, with further improvements identified. Overall, it is concluded that the Strategy has encouraged the pursuit of more beneficial reuse options or research projects for maintenance dredged material. In 2016, Ports Australia released the Environmental Code of Practice for Dredging and Dredged Material Management which establishes environmental principles for dredging and reusing, relocating, or placement of dredged material. All Great Barrier Reef World Heritage Area ports provide information in their Long-term Maintenance Dredging Management Plans regarding investigations and assessment of feasible options for beneficial reuse or placement of material if dredging cannot be avoided. This information is typically provided under an 'Examination of reuse, recycle and placement options' section of the Long-term Maintenance Dredging Management Plans.

In response to stakeholder feedback regarding assessment of dredged material management options, it is recommended that Great Barrier Reef World Heritage Area ports regularly review membership of Technical Advisory and Consultative Committees and communication plans. This would improve consultation and assist stakeholders understand port decision-making processes as part of dredged material management options assessment (recommendations 1 and 2).

Maintenance Dredging Strategy Principle 7
Applications to place material at sea will continue to abide by existing National Assessment Guidelines for Dredging 2009 (or any subsequent versions) and regulatory processes, including an assessment of: all feasible alternative disposal options sediment quality at both loading and placement sites in accordance with relevant regulation and guidelines to prevent toxic material being placed at sea how the sites may be impacted, with consideration of the marine environment and other uses of the area monitoring and management measures to control or mitigate impacts.

The National Assessment Guidelines for Dredging 2009 are recognised in the Strategy as the standard to assess sediment management options, and to determine management and monitoring requirements to control or mitigate impacts of the selected sediment management option.

The Great Barrier Reef World Heritage Area ports have applied for and obtained a range of updated statutory permits and approvals from state and federal regulatory agencies for long term maintenance dredging and offshore placement since the Strategy came into effect including at the:

• Port of Cairns (10 year permit)
• Port of Townsville (6 year permit)
• Port of Mackay (10 year permit)
• Port of Hay Point (10 year permit)
• Port of Gladstone (10 year permit).

Reflective of the Strategy and its guiding principles, these new permits applications have been supported by comprehensive impact assessments and additional monitoring effort, including:

• advanced sediment quality testing and analysis in accordance with National Assessment Guidelines for Dredging protocols
• extensive analysis of sediment processes including undertaking numerical modelling of dredge plumes and material resuspension (from both dredging and placement)
• using the modelling outputs to set out predictive zones of influence and zones of impact from dredging and placement activities for turbidity and light penetration
• setting water quality performance triggers for the adaptive management of sensitive environmental receptors that could be affected by during dredging and placement activities such as seagrass and coral reefs
• undertaking additional validation monitoring of actual maintenance dredging campaigns to ensure model results are accurately predicting impacts.

A review of these latest studies suggests that maintenance dredging activities are being assessed with the same robust and rigorous approach that are being taken for capital dredging projects.

Comprehensive consultation has been a significant component of the assessment requirements for state and federal agencies with jurisdiction over dredging and placement within the Great Barrier Reef World Heritage Area. The long-term maintenance dredging permits and approvals that have been obtained since 2016, have involved consultation and engagement with technical experts and key stakeholders through the port Technical Advisory and Consultative Committees. For those long-term permit applications for at-sea placement within the Great Barrier Reef Marine Park, a formal public information package and a mandatory public submission process was also undertaken. The documents released for comment are prepared in accordance with the Great Barrier Reef Marine Park Authority’s requirements and include specific information including:

• why and how maintenance dredging occurs at the port
• what specific activities are being proposed
• the environmental receptors and risks
• how risks are monitoring and managed
• the timeframes of activities and management of impact on other users
• who has been engaged and consulted
• where to get further information
• frequently asked questions.

The Strategy required development of Long-term Maintenance Dredging Management Plans to improve stakeholder confidence and environmental outcomes by identifying potential impacts of maintenance dredging activities, proposed measures and outcomes. The Strategy notes this may also allow longer-term approvals and facilitate better coordinated approval conditions from regulators.

Feedback received through the review provided differing perspectives on whether the Strategy had improved regulatory processes related to maintenance dredging. Regulatory agencies indicated application processes had been streamlined through the development of Long-term Maintenance Dredging Management Plans, however some suggested there is further opportunity to improve consistency across regulatory processes. Port authorities suggested assessment processes could be further streamlined, for example:

• consistency of information requirements for permit applications, management plans and monitoring between state and federal jurisdictions
• the transition process from capital to maintenance dredging
• timeframes for different assessment processes.

To address this feedback, Queensland Ports Association should consider engaging with regulators about potential opportunities to streamline and/or standardise elements of the application and assessment processes related to dredging and material placement.

Finding: Principle 7 is being applied however further improvements have been identified. All Great Barrier Reef World Heritage Area ports provide information in the Long-term Maintenance Dredging Management Plans about their investigations into feasible sediment management options, as well as information which supports any applications to place dredged material at sea. Great Barrier Reef World Heritage Area ports have received approvals for maintenance dredged material placement since introduction of the Strategy, with regulators and port authorities providing differing feedback on the efficiency of these processes. Queensland Ports Association should consider engaging with regulators about potential opportunities to streamline and/or standardise elements of the application and assessment processes related to dredging and material placement (Recommendation 3).

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Maintenance Dredging Strategy Principle 8

Great Barrier Reef World Heritage Area ports will undertake a consultative comparative risk-based analysis process encompassing environmental, economic, technical, operational and societal issues to determine the most suitable solution(s) for management of maintenance dredging material using a repeatable and structured methodology. Information and results of the comparative analysis process will be published in the Long-term Maintenance Dredging Management Plans.

The Guidelines for Long-term Maintenance Dredging Management Plans (the Guidelines) establish the comparative analysis framework to determine the most suitable solution/s for management of maintenance dredging material. The Guidelines explain that comparisons of options should involve a repeatable and transparent method against the key objectives that have been developed in consultation with key stakeholders (that is, the Technical Advisory and Consultative Committee). Further, decisions need to be based on both quantitative evidence and an evaluation of the important values to stakeholders. The Guidelines recognise that a single solution may not be optimal or possible and so the comparative analysis should consider a mix of options that could be utilised over the longer term.

During consultation one stakeholder suggested the methodology for multi-criteria analysis could be reviewed to give Matters of State Environmental Significance higher representation, and to ensure the costs of dredging and material placement were not considered higher than the ongoing environmental impacts/costs. Other stakeholders noted the Technical Advisory and Consultative Committees provide an opportunity to understand the considerations in analysing dredged material placement options.

The Guidelines present the Queensland Government’s expectation that the Technical Advisory and Consultative Committees will participate in the comparative analysis process (including multi-criteria analysis). This enables stakeholder feedback on the options development process to determine and assess the alternatives and assist in determining the most appropriate option.

A review of the Long-term Maintenance Dredging Management Plans reveals the documents outline the methodology for determining the most suitable solution for management of maintenance dredging. Long-term Maintenance Dredging Management Plans also indicate that Technical Advisory and Consultative Committees are involved in the comparative analysis process.

Case Study: Port of Gladstone Stakeholder Engagement and Comparative Analysis

A key component of the Gladstone Ports Corporation’s Sustainable Sediment Management Project was the stakeholder engagement and method for robust, repeatable comparative analysis. To ensure genuine and meaningful consultation was undertaken throughout the assessments, Gladstone Port Corporation’s process was based on Structured Decision Making. This approach encompasses both the technical consequences of an activity/option and the values stakeholders consider important. Three stakeholder forums were undertaken for the project, each with a different engagement goal: Forum 1 provided a project overview to the relevant stakeholders and gained an understanding of what they valued. Using previous stakeholder feedback and other external examples, the port drafted a list of sustainability values in the form of ten objectives and associated measures. During the forum the objectives and measures were challenged, built on, and refined resulting in 12 sustainability objectives and associated measures. This list was used by to undertake the technical options assessments. In Forum 2 the recommended options from the technical assessments were presented to the stakeholders, providing the group the opportunity to discuss in detail. The forum was also used to describe the online evaluation process and tool the stakeholders needed to complete to do their evaluation. Forum 3 was used to present and discuss the subsequent evaluation results and any feedback the stakeholders had with the options or the process. The aim of this forum was to narrow down the top scoring options to those worth progressing into more detailed feasibility studies.

Finding: Principle 8 is being applied, with further improvements identified. The Long-term Maintenance Dredging Management Plans outline the methodology used and results for determining the most suitable option for management of maintenance dredging. Long-term Maintenance Dredging Management Plans also indicate that Technical Advisory and Consultative Committees are involved in the comparative analysis process.

However, in response to stakeholder feedback, it is recommended ports regularly review membership of Technical Advisory and Consultative Committees (Recommendation 1). This will ensure stakeholder concerns are integrated into processes such as comparative analysis methodologies.

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Maintenance Dredging Strategy Principle 9

As part of the risk-assessment for maintenance dredging, Great Barrier Reef World Heritage Area ports must provide rationale for the type of dredger chosen for each annual maintenance dredging program, with regard to the equipment’s ability to undertake the necessary works, implement best practice environmental management measures, its technical and operational capabilities, and its cost effectiveness.

Maintenance Dredging Strategy Principle 10
Any new or alternative vessels or methods considered or proposed should result in environmental performance that is equal to, or better than, current equipment or methods used.

Maintenance Dredging Strategy Action 3

Ports will work together to ensure that an annual state-wide maintenance dredging program for the Trailing Suction Hopper Dredger Brisbane is developed to optimise environmental outcomes and operational efficiencies by: ensuring identified environmental windows, as well as any restrictions imposed on maintenance dredging permits are applied minimising the net risk of impacts at each port by adopting site-specific operating procedures avoiding unnecessary dredger travel and relocation. The programs will be made publicly available and the first program is to be completed for the 2017 dredging season.

The ports conduct regular hydrographic surveys of navigational infrastructure to assess port sedimentation and to plan and predict whether maintenance dredging is required at each port. Where hydrographic surveys indicate maintenance dredging is required, Great Barrier Reef World Heritage Area ports identify the most suitable dredger for maintenance dredging activities. Most annual maintenance dredging at Queensland ports is undertaken by the Trailing Suction Hopper Dredger Brisbane.

Since 2017, the Queensland port authorities have worked together to develop an annual maintenance dredging schedule for the Trailing Suction Hopper Dredger Brisbane. The dredge, based in Brisbane and operated by the Port of Brisbane Pty Ltd, was specifically designed and built for Queensland conditions with the vessel applying high standards of environmental management. The environmental management mechanisms are equivalent to the features installed in the latest Trailing Suction Hopper Dredger models used around the world and ensure environmental impact is minimised during the dredging works.

While the schedule varies from year to year as not all Queensland ports require dredging each year, the annual schedule explicitly identifies the environmental values and timing risks at each port and is designed to avoid environmental windows (for example, turtle nesting, coral spawning, prawn migrations) with a view to seeking to avoid or minimise impacts within the other constraints available.

To develop the state-wide dredging schedule, individual ports (including within and outside the Great Barrier Reef World Heritage Area) and the dredge operator consider the following issues:

• opportunities to minimise dredging requirements—the schedule is best initiated after the wet season when most sedimentation occurs to avoid the need for follow-up dredging
• opportunities to minimise environmental risks—port specific risk assessments suggest maintenance dredging is a low risk at all ports; however, dredging is avoided at particular times of the year at Queensland ports due to potential environmental risks
• permitting and approval conditions—the schedule is developed with consideration of permit restrictions at Queensland ports
• volumes of material to be dredged—the degree of siltation and its location within the channel, berth or swing basin determines the volume of material to be dredged and the duration of dredging at each port required to restore designated depths
• urgency of port dredging requirements—the urgency of dredging requirements varies from year to year depending upon the degree and location of siltation at each port
• dredge vessel maintenance including refit needs
• economic efficiencies—the schedule is designed to ensure ports are visited in a relatively linear fashion and avoid the need to “backtrack” wherever possible as this can result in increased costs, fuel usage and vessel emissions
• response to natural disasters including cyclones and flood events
• reducing carbon emissions.

Consistent with the Strategy, this schedule has been published annually on the Department of Transport and Main Roads website since 2017.

During consultation one stakeholder commented on the need for improved efficiency of dredging devices. In 2023 the Great Barrier Reef World Heritage Area port authorities commenced a joint assessment of options for future service delivery of their maintenance dredging requirements over the medium-to-long term. This process will consider principles 9 and 10 of the Strategy, noting new or alternative vessels or methods should result in environmental performance that is equal to, or better than, current equipment or methods used.

Great Barrier Reef World Heritage Area ports integrate Principle 10 into various operational strategies associated with maintenance dredging such as infrastructure planning to reduce dredging requirements, identifying dredging windows to improve environmental performance, and incorporating monitoring outcomes into adaptive management practices.

Finding: Principles 9 and 10 are being applied and Action 3 is complete. Since 2017, the Queensland Ports Association has prepared a schedule for Queensland-wide maintenance dredging of Queensland ports which is published on the Department of Transport and Main Roads website. The Trailing Suction Hopper Dredge Brisbane, which is generally used for maintenance dredging, was specifically designed and built for Queensland conditions to ensure environmental impact is minimised during the dredging works. In 2023 the Great Barrier Reef World Heritage Area port authorities commenced a joint assessment of options for future service delivery of their maintenance dredging requirements which will consider improved performance and efficiencies.

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Maintenance Dredging Strategy Principle 11
Prior to any maintenance dredging Great Barrier Reef World Heritage Area ports will identify and apply environmental windows supported by an evidence-based risk assessment. Particular consideration must be given to periods of coral spawning, seagrass recruitment, turtle breeding and periods immediately following severe weather events.

The Queensland Ports Association's schedule for Queensland-wide maintenance dredging of Queensland ports is prepared annually and published on the Department of Transport and Main Roads’ website (Action 3). The Queensland Ports Association reports that importantly, environmental risks associated with timing of maintenance dredging, whilst typically low, may also vary annually and that each port completes a port-specific environmental risk assessment as a key input to the development of the dredge schedule (consistent with the requirements of the Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports).

Seagrass communities at ports vary in condition and extent reflecting environmental conditions (for example cyclones or above average rainfall) experienced over the preceding years with some being in good condition whilst others are recovering or are in poor condition. Many years of dredge and seagrass monitoring indicate no environmental benefit would be gained by restricting maintenance dredging at all ports to a uniform and specific time of the year.

The Port of Hay Point maintenance dredging permits impose timing limitations on maintenance dredging activities, prohibiting dredging within seven days before or after predicted mass coral spawning events which typically occur between October and November each year. The Port of Townsville has proactively limited maintenance dredging at times during October to December to avoid coral spawning, and during times in August to September when a local cultural event (yacht race) occurs for navigational safety reasons.

Scheduling in Queensland is largely driven by avoiding maintenance dredging in the northern part of the state in the summer months to:

• avoid significant weather events during the wet season
• maximise dredging efficiency (as sediments are more settled in dry season)
• avoid adding further stress to environmental values such as seagrass which can be impacted by warmer water temperatures or coral which is at increased risk of bleaching
• avoid key breeding/major growth periods for environmental values.

Finding: Principle 11 is being applied. Environmental risks associated with timing of maintenance dredging, whilst typically low, may also vary annually and each port completes a port-specific environmental risk assessment as a key input to the development of the schedule for Queensland-wide maintenance dredging of Queensland ports.

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Maintenance Dredging Strategy Principle 12
Long-term Maintenance Dredging Management Plans will take into account any Reef 2050 Long-Term Sustainability Plan policy developments in relation to cumulative impacts, offsetting impacts and providing net benefits.

The Guidelines for Long-term Maintenance Dredging Management Plans promote consideration of cumulative impacts as part of the environmental risk assessment process that ports must undertake as part of the Long-term Maintenance Dredging Management Plan process. This process must determine the material short, medium, and long-term risks and uncertainties that need to be addressed in managing the dredging and placement activities, including consideration of cumulative impacts and net benefit.

In 2018, the Australian and Queensland governments jointly published the following two documents under the Reef 2050 Long-Term Sustainability Plan (Reef 2050 Plan) that the port authorities also take into consideration:

• The Cumulative Impact Management Policy defines cumulative impacts as “the interaction of effects between one or more impacts and past, present and reasonably foreseeable future pressures. Cumulative impact assessment takes into account direct, indirect and consequential impacts and the incremental and compounding effects of these impacts over time, including past, present and reasonably foreseeable future pressures” (page 3)
• The Net Benefit Policy defines net benefit as “an overall improvement in the condition and/or trend of a Great Barrier Reef value, or those actions which result in the net improvement” (page 3). Net benefits are focussed on delivering actions above and beyond offsetting impacts, which will restore or improve the condition of the Great Barrier Reef.

Great Barrier Reef World Heritage Area ports consider the cumulative impact and net benefit policies as part of the Long-term Maintenance Dredging Management Plans process. Cumulative impacts are also taken into consideration by the Great Barrier Reef World Heritage Area ports through ongoing review of their risk assessments, reviewing past performance of both maintenance and capital dredging campaigns, predictive modelling of impacts, and reviewing monitoring data and programs to look for observable trends and impacts.

New or updated technical assessments now routinely include consideration of cumulative impacts which assess the resilience of the receiving environment to withstand impacts from maintenance dredging and placement in the context of natural variability as well as considering the additive effects of other anthropogenic impacts. This includes consideration of short-term climate variability (for example El nino vs La nina cycles) as well as longer term chronic effects.

This process is aided by long-term data sets held by each port authority, such as seagrass monitoring programs, marine water monitoring programs (in many cases ongoing for approximately 20 years) and marine sediment monitoring programs. This data is regularly reviewed, often with the involvement of the experts on port Technical Advisory and Consultative Committees, to look for trends or changes to ambient conditions that could indicate impact or determine current and future resilience.

Ports are also considering future variability from climate change on maintenance dredge volumes. While there is generally less cyclones predicted in the Central and North Queensland region, there may be larger weather systems that will increase ambient bed resuspension that contributes to siltation of shipping channels as well as greater rainfall and flood runoff potential. This may increase the frequency and volume of maintenance dredging which has been factored into contingencies set in long-term permits which are mostly defined by annual volumetric limits.

While port authorities advise cumulative impacts, offsetting impacts and providing net benefits are considered, feedback received from some stakeholders suggested cumulative impacts of maintenance dredging were not presented and a greater focus on the cumulative impacts of dredging is required. The differing perspectives suggest communication between stakeholders and Great Barrier Reef World Heritage Area ports could be improved, particularly relating to work undertaken by Great Barrier Reef World Heritage Area ports to support the understanding of cumulative impacts, assessment and management.

Finding: Principle 12 is being applied, with further improvements identified. In 2018, the Australian and Queensland governments jointly released the Cumulative Impact Management Policy and the Net Benefit Policy under the Reef 2050 Plan which Great Barrier Reef World Heritage Area ports considered when developing Long-term Maintenance Dredging Management Plans. However, to address differing perspectives of stakeholders, it is recommended that Great Barrier Reef World Heritage Area ports regularly review membership of Technical Advisory and Consultative Committees and communication plans to ensure relevant stakeholders are consulted on cumulative impact assessment processes (recommendations 1 and 2).

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Maintenance Dredging Strategy Principle 13
Appropriate monitoring programs for maintenance dredging activities at Great Barrier Reef World Heritage Area ports will be: determined by a risk assessment process informed by ongoing port and regional monitoring programs activity and port-specific focused on environmental values and activities of higher risk or that are indicative of broader ecosystem health.

The Great Barrier Reef Outlook Report 2019 noted in general terms, that “ports within the Region [Great Barrier Reef] continue to be well managed”; but noted that:

“while ports conduct a diverse range and number of monitoring programs, there are gaps in the range, quality and consistency of data collected across ports generally. These gaps also apply to the presentation and availability of collected data, as evidenced by a review of the publicly accessible ports monitoring data (for example, seagrass data). Expanded monitoring and reporting programs focused on known risks have the potential to identify new or emerging threats to the Region. They can also demonstrate the absence of such threats, which may include significant deterioration in sediment quality or the incidence of invasive marine species” (p.204).

The World Heritage Committee has considered the state of conservation of the Great Barrier Reef World Heritage Area since 2011. In July 2021 the World Heritage Committee asked Australia to submit an updated report on the conservation status of the Great Barrier Reef (a previous report was submitted on 1 December 2019) and invite an expert monitoring mission to visit the Great Barrier Reef and assess its conservation status. The Joint United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Centre/ International Union for Conservation of Nature (IUCN) Reactive Monitoring Mission to the Great Barrier Reef took place in March 2022. The Report on the Reactive Monitoring Mission to the Great Barrier Reef (Australia), 21-30 March 2022, one of the many inputs that informed the World Heritage Committee's decision to consider the Great Barrier Reef for the List of World Heritage In Danger, was released in November 2022. It included 10 High Priority Recommendations, and 12 Other Recommendations, including Other Recommendation O1 which referred to the Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports (the Strategy):

“Undertake the comprehensive and transparent scientific assessments recommended in the Maintenance Dredging Strategy, ensuring the results are made publicly available regarding the impact of maintenance dredge spoil dumping within the GBR [Great Barrier Reef], to guide and inform enhanced measures to minimize the impact of dredge spoil on the property” (p.7, 29).

As identified in the Strategy, and the Great Barrier Reef Outlook Report 2019, all ports undertake a range of ambient and project specific monitoring activities. In this context, the Strategy has provided a common framework for the ports to approach its monitoring strategy while not limiting innovation and site-specific initiatives. Stakeholders recognised the Strategy has resulted in positive outcomes at ports including new project initiatives and consideration of the Great Barrier Reef’s outstanding universal value.

The majority of port monitoring information is publicly available on port authority websites, in annual reports and shared through partnership programs such as the regional report cards.

Scientific assessments and research projects at Great Barrier Reef World Heritage Area ports are summarised in the section below.

Finding: Principle 13 is being applied, with further improvements identified. All Great Barrier Reef World Heritage Area ports undertake a range of ambient and project specific monitoring activities, scientific assessments, and research projects. The Strategy has provided a common framework for the ports to approach monitoring strategies while not limiting innovation and site-specific initiatives. However, to address concerns in the Great Barrier Reef Outlook Report 2019 and the Report on the Reactive Monitoring Mission to the Great Barrier Reef (Australia), 21-30 March 2022 regarding transparency/consistency of information, it is recommended Queensland Ports Association host regular forums with government agencies and port authorities. These forums can be used to exchange information, new port initiatives, data, research findings and experiences (Recommendation 3).

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The following scientific assessments, initiatives and research projects support the implementation of the Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports (the Strategy) at Great Barrier Reef World Heritage Area ports.

Long-term seagrass monitoring partnership

Great Barrier Reef World Heritage Area ports have funded a seagrass monitoring and research partnership with James Cook University for more than 27 years. The program assesses seagrass meadows in all commercial trading ports within the Great Barrier Reef World Heritage Area and extends to the Torres Strait and Gulf of Carpentaria.

Queensland Seaports Environmental DNA Surveillance program (Q-SEAS program)

Since 2019, Queensland ports have partnered with the Queensland Department of Agriculture and Fisheries to voluntarily implement the Q-SEAS program for early warning detection of invasive marine species. The Q-SEAS program builds on regimes that Queensland ports have had in place for several decades and incorporates world leading molecular techniques to detect the presence of invasive marine species at key ports. This methodology provides information on potential risk to movement of dredging equipment, as well as likelihood of pest species being encountered within the dredge material, and complements assessment done during the sediment analysis plan implementation process.

Sediment Sampling Analysis

Great Barrier Reef World Heritage Area ports have regular sediment sampling and analysis programs. In accordance with these programs, all dredge material is tested to ensure that it is satisfies the requirements of the National Assessment Guidelines for Dredging 2009. Sampling and analysis are undertaken by experienced consultants and accredited laboratories and all ports routinely compare sampling methods and results, including approaches to any emerging contaminants of concern. Under these guidelines, contaminated material is not allowed to be placed at sea.

Sustainability

All four port authorities managing Great Barrier Reef World Heritage Area ports have a significant sustainability agenda. This includes the implementation of sustainability strategies and initiatives aligned to the United Nations Sustainable Development Goals. Key issues addressed by ports typically include:

• best practice environmental monitoring and management
• transition to renewable energy
• climate change adaptation and decarbonisation
• Traditional Owner partnerships
• inclusive workplaces
• technology and innovation
• improving resource efficiency and reducing waste.

Queensland ports have an active sustainability and environment working group that collaborate on key issues.

Each port authority also works at a national level to support Ports Australia’s leadership on sustainability which included input into the Port Sustainability Strategy Development Guide released in 2020 which was a first of its kind for an industry group in Australia.

Globally, Ports Australia are active members of the World Port Sustainability Program which aims to demonstrate global leadership of ports in contributing to the Sustainable Development Goals of the United Nations.

Ports North initiatives

Annual maintenance dredging is undertaken at the Port of Cairns. Examples of Ports North’s research initiatives and investment are below.

The Port of Cairns Long-term Maintenance Dredging Management Plan 2021-2032 documents:

• multiple hydrodynamic coastal modelling studies have been conducted at the Port of Cairns (refer section 6)
• the Trinity Inlet Management Program that documents the environmental, social, and economic values surrounding the Port of Cairns since the 1990s (refer sections 3.12 and 5)
• Five yearly benthic habitat studies are undertaken at and adjacent to the Port of Cairns dredged material placement location.

The Cairns Shipping Development Project:

• required a comprehensive Environmental Impact Statement study
• utilised a research partnership with James Cook University to derive light thresholds for seagrasses of the Great Barrier Reef World Heritage Area, this was used in to inform the Dredge Management Plan
• utilised a land-based placement facility, demonstrating a sustainable sediment management solution
• required research to define and validate fine sediment generation during dredging.

At the Port of Cairns periodic verification of dredge and placement plumes that have been observed and recorded through field turbidity monitoring was conducted in 2019 and 2022. The data is used to validate hydrodynamic model predictions.

A routine hydrographic survey program monitors sediment in-fill and informs understanding of dredging requirements at the Port of Cairns.

Port of Townsville Limited initiatives

Annual maintenance dredging is undertaken at the Port of Townsville. Port of Townsville research initiatives and investment are below.

The Port of Townsville has been monitoring and recording environmental data for more than 20 years in Cleveland Bay, including:

• real-time water quality monitoring
undertaken in Cleveland Bay and Geoffrey Bay for temperature, conductivity, and turbidity.
• a benthic infauna recovery study to determine the recovery rate of benthic infauna in the at-sea dredged material placement area in Cleveland Bay.

The Port of Townsville Channel Upgrade project monitoring programs included dolphins, shorebirds, seagrass, coral, water quality, and underwater noise.

The Port of Townsville is undertaking a saline dredged material trial for beneficial reuse with several local partners. This trial is to determine if using dredged material in a Groundswell methodology would provide suitable conductivity levels for terrestrial usage. The dredged material is being combined with terrestrial organic waste under treatment and then tested to determine if conductivity levels drop over time. This trial will determine if there is an opportunity for beneficial reuse of dredged material outside the normal saline applications of beneficial reuse programs (for example, general soil improvements).

The Port of Townsville is a partner of, and hosts, the Dry Tropics Partnership for Healthy Waters, a collaboration between community, industry, science, research and government to produce an annual report card on the health of Townsville’s Dry Tropics catchments and waterways, and encourage collective action for waterway improvements. ArcGIS StoryMaps have been developed on seagrasses in Cleveland Bay and hydrology and hydrodynamics of Cleveland Bay.

Environmental and social values surrounding the Port of Townsville have been identified.

Other specific research projects include:

• natural and dredging related turbidity regimes in Cleveland Bay 2019
• risk assessing dredging activities in shallow water mesophotic reefs.

North Queensland Bulk Ports Corporation Limited initiatives

Since commencement of the Strategy in 2016, maintenance dredging was undertaken in the Port of Abbot Point in 2017, Port of Hay Point in 2019 and in the Port of Mackay in 2020. North Queensland Bulk Ports has a comprehensive program of environmental monitoring that is reviewed annually. It is developed on a port-by-port basis to ensure environmental issues in each port are being adequately monitored. Examples of North Queensland Bulk Ports research initiatives and investment are below.

Ambient, impact and adaptive monitoring of water and air quality, seagrass, coral are published annually for all three North Queensland Bulk Ports in the Great Barrier Reef World Heritage Area. The summarised results and trends are also provided as dashboards:

• coral monitoring
• seagrass monitoring.

The monitoring program forms part of the North Queensland Bulk Ports and James Cook University partnership, which has won the Outstanding Collaboration for National Benefit category for the Business and Higher Education Round Table award.

Sustainable sediment management assessments are undertaken by North Queensland Bulk Ports at each of its major ports to understand natural sediment transport mechanisms, including the contribution of dredging and placement activities to natural resuspension, and setting site specific environmental thresholds in relation to natural turbidity concentrations and adaptive management measures.

From 2015-2017, North Queensland Bulk Ports undertook an extensive sustainable sediment management research project to investigate the most sustainable way to manage accumulated sediment in and around the Port of Hay Point. This approach was replicated for the Port of Mackay from 2020–2022.

North Queensland Bulk Ports is a founding member of the Mackay-Whitsunday-Isaac Healthy Rivers to Reef Partnership (since 2014) and is the largest data contributor for the annual report cards because of the extensive ambient marine monitoring program for coral, water quality and seagrass.

The Whitsunday Water Quality Monitoring Blueprint for Tourism Operators is funded by the partnership between North Queensland Bulk Ports and the Australian Government’s Reef Trust and the Great Barrier Reef Foundation.

North Queensland Bulk Ports is a major project partner of the Turning Rubble to Reef in the Mackay Whitsundays project that seeks to install concrete habitat reef modules to emulate natural fish habitat in the Mackay offshore marine environment.

North Queensland Bulk Ports funded James Cook University to study manta rays aggregation at Holbourne Island (off the Port of Abbot Point) capturing photographs of the manta rays’ distinct markings and deploying satellite and acoustic tracking tags.

North Queensland Bulk Ports collaborates with Traditional Owners in the Port of Abbot Point to monitor turtle nesting activity, hatch success and radio tag rehabilitated turtles.

Gladstone Ports Corporation initiatives

Annual maintenance dredging is undertaken at the Port of Gladstone. Gladstone Ports Corporation research initiatives and investment are below.

An ecosystem research and monitoring program was undertaken from 2011–2022, with targeted ecological research programs across a broad range of species and habitats in the Port Curtis region in the Port of Gladstone, has been undertaken.

The monitoring program 2018–2023 for the Port of Gladstone includes sediment sampling, plume monitoring, water quality sampling, seagrass, reef and benthic invertebrate monitoring as well as hydrographic surveys.

Long term annual monitoring of selected coastal meadows and five yearly port wide monitoring, including deep-water meadows and seagrass monitoring is also undertaken.

A sustainable sediment management project has been developed to help obtain a robust, well considered, long term solution for the management of maintenance dredging sediment.

Gladstone Ports Corporation delivered a Biodiversity Offset Strategy which funds projects for habitat enhancement for the Port of Gladstone.

Gladstone Ports Corporation is a founding member and long-term contributor to the Port Curtis Integrated Monitoring Program, established in 2001, a collaborative monitoring program that conducts ambient mid to far field monitoring of water bodies for Port Curtis.

Gladstone Ports Corporation is a contributor to the Fitzroy Partnership for River Health which produces annual ecosystem health report cards for the Fitzroy Basin as well as numerous additional reports on all aspects of waterway health.

Gladstone Ports Corporation is a member of the Gladstone Healthy Harbour Partnership, producing a Report Card which synthesises data from 78 measures to develop 'indicators' for environmental, social, cultural, and economic components of harbour health. This returns an overall score, as well as individual component scores.

Other specific research projects include:

• sediment provenance and texture mapping which used a multi-faceted technique to help ascertain the sources of sediments that occur within the Port of Gladstone
• the economic impact of not dredging, which provided an understanding the impact to each port if no sediment management was undertaken, and when that impact would be realised
• development of the light-based trigger (benthic photosynthetically active radiation) for Gladstone
• Memorandum of Understanding with Central Queensland University which includes Coastal Marine Ecosystems Research Centre
• Doctor of Philosophy (PhD) Scholarship: Working with Nature Investigations for Seawall Designs in the Port of Gladstone, co-funded with Central Queensland University—this research aims to improve our understanding of ecological engineering options through the installation and monitoring of a ‘living seawall’ that includes the keystone habitat forming species
• PhD Scholarship: Economic valuation of a coastal Nature-based Solution using Choice Experiments, co-funded with Central Queensland University—this research is linked to the above scholarship and aims to provide an appropriate method to value the habitat improvements created
• fine-grained sediment and flocculation—the aim of the research is to improve the understanding of the behaviour of fine-grained sediment and the accuracy of hydrodynamic modelling (by the incorporation of flocculation).

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Maintenance Dredging Strategy Principle 14
Great Barrier Reef World Heritage Area ports will apply adaptive management strategies and continual improvement processes to ensure that leading practice management is maintained. This will involve monitoring the effectiveness of strategies put in place and assessing potential benefits from altering or applying new management measures.

The Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports (the Strategy) requires monitoring and reporting activities undertaken by Great Barrier Reef World Heritage Area ports under a Long-term Maintenance Dredging Management Plan to be regularly and formally assessed to ascertain the effectiveness of the strategies put in place to manage impacts on the Great Barrier Reef’s environmental condition. The Strategy seeks management measures to be altered at appropriate times to consider any lessons learnt from monitoring results and to incorporate any new science or technologies that will improve management strategies.

Some adaptive management practices applied by Great Barrier Reef World Heritage Area ports are described elsewhere in this document:

• reducing maintenance dredge volumes
• beneficial reuse
• scheduling of the state-wide maintenance dredging program
• monitoring advances
• reporting advances.

Other examples of adaptive management practices that have been adopted by some Great Barrier Reef World Heritage Area ports include:

• minimising dredging in the wet season to avoid adding stressors on a potentially stressed system (that is, during or after periods where water temperatures are elevated, and the risk of coral bleaching has increased)
• adapting at-sea placement practices to preferentially place the material in the deeper sections of approved placement areas (to reduce material re-suspension by the action of normal waves and tidal currents)
• tracking vessel movements during dredge campaigns using Global Position System transponders onboard the dredge with live location feeds on interactive webpages
• standardising the development, use and review of Long-term Maintenance Dredging Management Plans, environmental management plans and associated monitoring procedures
• embedding a continuous improvement cycle for maintenance dredging.

Finding: Principle 14 is being applied. Great Barrier Reef World Heritage Area ports adopt adaptive management processing during dredging, dredged material management, monitoring and reporting processes.

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Maintenance Dredging Strategy Principle 15
Maintenance dredging, monitoring and reporting programs by Great Barrier Reef World Heritage Area ports will be available for inclusion in the Integrated Monitoring and Reporting Program for the Reef 2050 Long-Term Sustainability Plan (Action GA15).

Maintenance Dredging Strategy Principle 16
Great Barrier Reef World Heritage Area ports will provide mechanisms for stakeholders to access data and information from monitoring programs.

Maintenance Dredging Strategy Action 4
Great Barrier Reef World Heritage Area ports will publish a publicly available report on all maintenance dredging activities annually, including timelines, volumes, evaluation of dredged material disposal options and spoil placement locations, and outcomes of monitoring.

The Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports (the Strategy) recognises reporting is an important part of evaluating performance and guiding adaptive management, and that transparency and ease of access to monitoring data, as well as other maintenance dredging activity information, will allow better accountability and ensure stakeholders are informed on all aspects of dredging including programming and outcomes of monitoring and management activities.

Components of port-related monitoring data (such as seagrass health and water quality) are contributed to the relevant regional healthy waterway partnership report card. These report cards are used to report on the condition of waterways that flow to the Great Barrier Reef World Heritage Area through the Reef 2050 Long-Term Sustainability Plan (Reef 2050 Plan).

The Reef 2050 Plan required development and implementation of the Reef 2050 Integrated Monitoring and Reporting Program. The Reef 2050 Integrated Monitoring and Reporting Program is a partnership involving the:

• Reef Authority
• Australian Department of Climate Change, Energy, the Environment and Water (DCCEEW)
• Australian Institute of Marine Science (AIMS)
• Integrated Marine Observing System (IMOS)
• Commonwealth Scientific and Industrial Organisation (CSIRO)
• Queensland Department of Environment, Science and Innovation
• Traditional Owner members.

The Reef 2050 Integrated Monitoring and Reporting Program partners have been developing the Reef 2050 Integrated Monitoring and Reporting Program Data Management System project that will include building a cloud-based system to enable automated data management processes. The Reef Knowledge System is the online access point for Reef 2050 Integrated Monitoring and Reporting Program, with parts of it accessible to the public to find Great Barrier Reef data and tools. It provides a ‘first stop shop’ or portal, linking to monitoring information drawn from multiple sources, links to program partner systems and interactive maps and information.

While ports make data available through various initiatives under the Reef 2050 Plan (such as healthy waterway partnership report cards), port data is not currently integrated into the Reef Knowledge System. As the system evolves, there is opportunity for Great Barrier Reef World Heritage Area port authorities and Reef 2050 Integrated Monitoring and Reporting Program partners to integrate maintenance dredging, monitoring and reporting datasets.

From a reporting perspective, the Strategy has established a common framework for all Great Barrier Reef World Heritage Area ports. Development of the Long-term Maintenance Dredging Management Plans has ensured the consolidation of information from several port documents (including key findings of previous studies, assessments and lessons learned) into the one planning document whereas previously these would have been separated into different documents and managed by different teams within the port organisational structure. This assists the ports to ensure comprehensive management of maintenance dredging activities and improves transparency for stakeholders, regulators, and the community around how maintenance dredging and placement activities will be undertaken. It also enables measurement and review of performance. In this context, the Strategy has resulted in much more structured reporting of maintenance dredging activities including:

• quarterly reports from port authorities to the Department of Transport and Main Roads including updates to the annual risk assessment
• a schedule for Queensland-wide maintenance dredging of Queensland ports and an annual review of maintenance dredging activities, published on the Department of Transport and Main Roads website.

Each Great Barrier Reef World Heritage Area port has established a Technical Advisory and Consultative Committee to assist in the management of dredging and dredged material placement activities within the port. The Technical Advisory and Consultative Committees have been established in line with the National Assessment Guidelines for Dredging 2009 and are important consultative mechanisms to assist ports, other proponents, and regulatory agencies to access local knowledge and reconcile various stakeholder interests. The Technical Advisory and Consultative Committee members are expected to be drawn from relevant federal, state and local government organisations, Traditional Owners, community groups, research institutes, and other relevant stakeholders whose activities may be influenced by maintenance dredging or placement activities. The intent is for Technical Advisory and Consultative Committee members to have access to information from monitoring programs and provide technical input, oversight, or local expertise in identifying or addressing local environmental aspects relating to maintenance dredging and dredged material placement activities within the port.

Sustainable sediment management studies, such as those being undertaken by North Queensland Bulk Ports and Gladstone Ports Corporation, have also included specific consultation and engagement activities, including stakeholder working groups and advisory forums. These processes ensure stakeholders have a strong understanding of the latest scientific understanding around sediment processes and an opportunity to be involved in the material management options.

Through advances in technology, real time telemetered water quality monitoring data and results during dredge campaigns are also increasingly being made available by the port to Technical Advisory and Consultative Committees and regulators. In some cases, the public can also access and view this data on port authority websites such as Cleveland Bay buoy data at the Port of Townsville.

The Great Barrier Reef World Heritage Area ports also continue to invest in, and publish, targeted research that assists in understanding the impacts and appropriate management and monitoring techniques of the ports with local and regional partners.

Finding: Principles 15 and 16 are being applied, with further improvements identified. Great Barrier Reef World Heritage Area ports share maintenance dredging, monitoring and reporting data on their websites and with relevant organisations such as regional healthy waterway partnership report cards. The online interfaces and tools for Reef 2050 Integrated Monitoring and Reporting Program are under development and as such relevant data from Great Barrier Reef World Heritage Area ports is not currently integrated.

Actions 4 is complete. To meet Action 4, QPA has prepared an annual review of activities of the maintenance dredging program since 2018 outlining environmental performance, including timelines, volumes, evaluation of dredged material placement locations, and outcomes of monitoring.

Great Barrier Reef World Heritage Area ports use a large variety of mediums to enable stakeholders to access data and information from monitoring programs. However, a consistent theme in feedback from stakeholders was continued improvement of communication and transparency. It is recommended port authorities and regulators regularly exchange information, data and research findings, and work with the Reef Authority to integrate data into the Reef 2050 Integrated Monitoring and Reporting Program Data Management System as it is developed (recommendations 3 and 4). Reviewing Technical Advisory and Consultative Committee membership and communication plans would also address the stakeholder concerns (recommendations 1 and 2).

Maintenance Dredging Strategy Principle 17
Review of this Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports

Maintenance Dredging Strategy Action 5
The Department of Transport and Main Roads will review this Maintenance Dredging Strategy for Great Barrier Reef World Heritage Area Ports in five years to assess its effectiveness in achieving the objectives of ensuring the ongoing protection of the Great Barrier Reef’s outstanding universal value and the continued operating efficiency of Great Barrier Reef World Heritage Area ports.

This review fulfills Principle 17 and Action 5 to review the Strategy to assess its effectiveness in achieving objectives.

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