As a World Heritage-listed site, the Great Barrier Reef (GBR) is one of the most scrutinised natural wonders of the world when it comes to impact from industry.
The world’s largest coral reef, it has more than 3000 individual reef systems and coral cays, and is home to an abundance of marine life.
So, when the Port of Townsville, located right on the GBR’s doorstep, was due for expansion, strict environmental monitoring and protection mechanisms were implemented.
The Port of Townsville Limited (POTL) engaged GHD for a five-year program (beginning November 2018) to monitor before, during and after dredging activity.
GHD’s collaborative approach brought together teams from across Australia and external specialists to deliver a leading practice water monitoring system to enable real-time management of channel upgrade (CU) dredging.
As a result, POTL can now undertake capital works with confidence that compliance to permitted conditions is achieved, sensitive receptors such as nearby fringing reefs and seagrass beds are protected, and reputational risks are managed.
About the project
As the largest commercial port in northern Australia, the Port of Townsville is an essential component of Queensland’s transport network, but, at just 92 metres wide, its shipping channel is one of the narrowest in the country.
The 14.9-kilometre shipping channel is dredged annually to maintain navigable depths.
At present, vessels up to 238 metres long can safely access the port. However, as ships are getting larger, the port has to adapt to accommodate the needs of North Queensland's mining, defence, agriculture, construction, vehicle and tourism industries.
A long-term, strategic development plan for the port, the $1.6 billion Port Expansion Project (PEP) includes capital dredging for channel widening, land reclamation to develop a new outer harbour, wharves, and associated infrastructure to be constructed by 2040.
Stage one of the Port Expansion Project (the $193 million Channel Upgrade Project) will deliver a wider shipping channel and a 62-hectare Port Reclamation Area.
This will allow vessels of up to 300 metres long to safely access the port.
The challenge
The port operates in a sensitive environment, home to threatened species and habitats that support them.
As the tropics experiences extreme weather events – and conditions vary between wet and dry seasons – the team had to capture those variations, as well as understand the resilience of the ecosystem.
The team had also experienced ongoing equipment damage from inquisitive turtles.
Given these factors, the team needed to design a system that would satisfy permit conditions, manage large volumes of data, and withstand environmental challenges.
Our solution
The CU permit conditions prescribe locations, parameters and timing for monitoring, which meant an ‘off-the-shelf’ solution was not sufficient.
Instead, GHD developed a customised, integrated approach that brought together expertise and technology in three key areas: equipment; data management; and mitigating equipment damage.
Equipment
GHD’s approach incorporates recent scientific advances and, includes monitoring underwater light characteristics, additional to those prescribed under CU permits.
To help POTL meet the CU conditions, GHD is partnering with scientists from three organisations, including university, tech/hardware developers, and specialist subconsultants. The team custom-built monitoring equipment to meet approval specifications and the field team, led by GHD Townsville, includes specialists with experience in each aspect of the equipment.
This allows GHD to provide POTL with a compliant data set that also tests and verifies emerging techniques. This evidence-based R&D approach will demonstrate to regulators the applicability of emerging techniques to dredging projects and has been endorsed by industry leaders on the Independent Technical Advisory Committee (ITAC).
The monitoring system includes a dashboard for live data viewing during dredging, enabling early warning of potential for impact to sensitive receptors (from CU activities, or larger scale events such as thermal coral bleaching), and facilitating proactive management of CU activities for compliance, reputational management, and protection of sensitive receptors.
Data Continuity
GHD’s ambient marine water monitoring program (the precursor to CU monitoring) ended in October 2018 and the custom-built CU equipment was not due to arrive until mid-2019.
To manage the six-month data gap, GHD implemented an interim monitoring program (deployed during the 2018-19 Wet Season, inclusive of the February 2019 flooding), allowing it to extend and expand its ambient program using equipment owned by GHD and its subconsultants.
This recorded valuable data for the POTL and the broader scientific community, which otherwise would not have been achieved. As a result, the construction schedule was not impacted by the potential lack of baseline data.
Mitigating equipment damage
To investigate the cause of reported equipment damage, underwater video cameras were mounted to the equipment frame. These showed turtles being attracted to and subsequently damaging equipment.
In collaboration with POTL, GHD designed an equipment frame to deter the turtles while maintaining data integrity.
Early testing of the frame showed it is a feasible long-term solution, enabling POTL to comply with monitoring at all locations specified in CU permits.
The outcome
This project will deliver a technically robust program to enable POTL to actively manage dredging activities for compliance and reputational risk. It:
- Provides access to leading capability across the GHD network, irrespective of geography.
- Provides a results synthesis for active, educated community stakeholders.
- Incorporates R&D activities as an early investment in future stages of port expansion works.
Incorporates local providers – enabling POTL to meet its commitments to supporting local employment.
Benefits to industry
This project also demonstrates many benefits to the industry, including providing suppliers with an opportunity to test, and defend (via ITAC review) emerging technologies alongside currently accepted practices.
Its results, and associated education of regulators, will be applicable across the industry, and the methods will be relevant to other ports in Australia, and globally.
The detailed, robust data set will enhance understanding of complex systems, including managing future dredging activities next to sensitive receptors, thereby contributing to academia and our overarching body of knowledge.
Meet Anna
Anna is a Senior Ecologist/Environmental Scientist at GHD, where she works on coastal development projects focusing on marine and estuarine ecology, water quality and sediment quality. Anna has in-depth knowledge (pun intended) of approvals and permitting processes for marine and estuarine projects, and completed a number of assessments around Australia and internationally.
For more information, please contact Anna at Anna.Boden@ghd.com
Stay connected to our expert insights
POTL has a strong collaborative relationship with GHD’s project team, built over a long period and we highly value the expertise, advice and skills it offers. Key to the success of our strong working relationship is the team’s willingness to openly engage with us, incorporating our knowledge and experience, as well as their own into project delivery. The team’s depth and understanding of the context of the work undertaken, ability to value add, and provide a high-quality outcome, demonstrates the success of our continuing working relationship.
Melinda Louden
Manager Environment and Planning, Port of Townsville Limited
