To ensure the safe movement of vessels in and around port areas, dredging activities are undertaken at ports around the world.
Tasmania's multi-port system is no exception and TasPorts regularly undertakes dredging activities, in line with its Long-Term Dredge Management Strategy.
Through this strategy, TasPorts is committed to enabling our customers and industry partners, whilst upholding maritime and environmental standards.
By ensuring the water is deep enough for ships to prevent grounding on the seafloor.
A well dredged port enables smoother and faster loading and unloading of cargo from ships.
Efficient and safe port operations support business and industries using the port. If not completed, operations can be restricted, negatively impacting our customers and local economies.
Maintenance dredging enables our ports to adapt to sediment changes and build up that naturally occur over time from flooding, storms, ocean swell and tidal movements.
The Port of Devonport is fed by the Mersey catchment system, which annually accumulates approximately 40,000m3 of sediment, therefore requires regular maintenance dredging.
Between March and June, TasPorts completed a 12-week dredging campaign, which relocated more than 250,000 cubic metres of dredged material to an approved offshore disposal ground. This campaign successfully increased depths across the port, strengthening safe and reliable access for all vessels using the Port of Devonport.
TasPorts completed 24/7 water quality monitoring throughout the project. As a key achievement, monitoring confirmed that dredging activities did not result in any sustained dredging-related increases in turbidity, a key indicator of water quality. Observed variations were short-term and consistent with natural environmental conditions, with investigations attributing these to weather influences and routine equipment maintenance rather than dredging activities.
To ensure the integrity of its data, TasPorts regularly serviced and calibrated its monitoring equipment throughout the campaign. This included equipment calibrations and inspections every four to six weeks, in addition to regular water sampling throughout the campaign.
This dredging campaign is the first to be completed under TasPorts' 10-year Sea Dumping Permit, issued by the Australian Department of Climate Change, Energy, the Environment and Water (DCCEEW). Together with TasPorts’ Long-Term Dredge Management Strategy, this will guide future campaigns to maintain safe and efficient access to the port and support Tasmania’s trade.
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TasPorts has deployed six water quality monitoring buoys near the Devonport port area and Mersey River, which are providing 24/7 real-time water quality data.
Supported by a dedicated Port of Devonport Adaptive Monitoring and Management Plan, TasPorts will appropriately respond to any identified changes in turbidity levels throughout the project.
The early deployment of the water quality monitoring buoys support baseline data collection, enabling TasPorts to effectively monitor and respond to any changes in water quality during the dredge campaign. Rolling 6-day and 15-day averages of live water quality monitoring data is available through the link below.
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