Decades of Dredging at Gippsland Lakes: From April Hamer to Modern TSHD Technology

Introduction

Gippsland Lakes, Australia’s largest inland waterway system, is not only a natural treasure but also a vital maritime passage connecting regional ports to Bass Strait. Since the creation of a permanent Entrance in 1889, the lakes have faced ongoing challenges due to oceanic sand drifting into navigation channels. Over time, this sediment buildup has required continuous intervention. From the early use of the April Hamer side-casting dredge to the advanced deployment of Trailing Suction Hopper Dredge (TSHD) technology, the evolution of dredging operations at Gippsland Lakes is a testament to innovation and commitment to safe, navigable waters.

1. The Historical Significance of the Gippsland Lakes Entrance

The permanent Entrance connecting Gippsland Lakes to Bass Strait was completed in 1889, revolutionizing trade and navigation in eastern Victoria. However, the new channel created a pathway for sand to drift into the lakes, gradually forming an offshore sandbar known as “the Bar.” This buildup threatened the safety and reliability of maritime access, prompting successive Victorian Governments to implement long-term dredging strategies.

2. The Era of the April Hamer Side-Casting Dredge (Pre-2008)

For more than thirty years, the April Hamer, a side-casting dredge, played a central role in maintaining access through the Bar at Gippsland Lakes. Operating through a method of cutting and displacing sand laterally, the dredge maintained a narrow channel that allowed vessels to move between the lakes and Bass Strait.

Despite this effort, the Bar continued to expand, accumulating millions of cubic metres of sand. The limitations of the side-casting approach became increasingly evident, and by the early 2000s, it was clear that a more efficient dredging method was needed to keep the Gippsland Lakes accessible year-round.

3. Transition to TSHD Technology at Gippsland Lakes

In 2008, Gippsland Ports began employing Trailing Suction Hopper Dredge (TSHD) technology to address the growing challenges posed by sand ingress. TSHD vessels work by trailing suction pipes along the seabed, vacuuming sediment into an onboard hopper. Once filled, the vessel deposits the material at approved offshore sites or designated zones.

Annual TSHD dredging programs were launched, typically lasting four to eight weeks depending on sediment buildup. This modern method allowed for more efficient removal of sand from both the Bar and the Entrance Channel, significantly improving navigation reliability and port safety at Gippsland Lakes.

4. Tommy Norton: A Purpose-Built TSHD for Gippsland Lakes (2017–Present)

A major milestone came in 2017 with the acquisition of Tommy Norton, a custom-designed TSHD built specifically to maintain Gippsland Lakes. Unlike previous short-term campaigns, Tommy Norton enables year-round dredging, allowing for proactive, consistent management of sediment accumulation.

The TSHD Tommy Norton is equipped with cutting-edge technology, making it highly effective in maintaining the Entrance Channel and offshore Bar. Its ability to operate continuously means that dredging is now preventive rather than reactive, ensuring uninterrupted navigability for both commercial and recreational vessels within Gippsland Lakes.

5. Inner Channel Maintenance with Cutter Suction Dredging

While the offshore Bar is managed using TSHD technology, the inner channels of Gippsland Lakes require a different approach. For decades, Gippsland Ports has used Cutter Suction Dredges (CSDs) to manage sedimentation in shallower areas closer to Lakes Entrance.

Initially, dredged material was discharged onto nearby land or into adjacent waters. Since 2001, however, operations have been streamlined through a Sand Transfer Station (STS), which enables the dredged slurry to be pumped into the surf zone via two beach outfalls, located roughly one kilometre east and west of the Entrance. This method not only maintains channel depth but also supports beach nourishment and coastal protection.

6. Protecting Ecosystems: Rigby Island Buffer and Seasonal Exclusion

Environmental sustainability is a priority in dredging operations at Gippsland Lakes. One such measure is the establishment of the Rigby Island Buffer Zone, a protected area for migratory bird breeding. Dredging activities in this zone are suspended during exclusion periods to avoid disrupting sensitive wildlife.

This approach reflects Gippsland Ports’ commitment to balancing essential infrastructure work with environmental conservation. By timing dredging programs around breeding seasons and applying adaptive strategies, the region has become a model for responsible maritime management.

7. Future Directions: Sustaining Dredging at Gippsland Lakes

With ongoing sediment inflow and the evolving demands of maritime transport, the future of dredging at Gippsland Lakes will rely on continued innovation. The integration of automated systems, real-time data analytics, and AI-assisted modeling may soon enhance the efficiency and precision of TSHD and CSD operations.

Climate change also brings new challenges, including rising sea levels and more frequent extreme weather events. These conditions may accelerate sand ingress, necessitating even more robust dredging responses. Gippsland Ports is well-positioned to adapt, thanks to its investment in long-term infrastructure like the Tommy Norton TSHD and its commitment to best-practice environmental stewardship.

Conclusion

The story of dredging at Gippsland Lakes is one of evolution—an ongoing journey from the era of the April Hamer to the modern capabilities of Tommy Norton. Through the adoption of TSHD technology and environmentally sensitive practices, Gippsland Ports has ensured that the lakes remain open, safe, and navigable for generations to come.

Dredging at Gippsland Lakes isn’t just about moving sand; it’s about preserving access, supporting local economies, and safeguarding ecological treasures. With advanced TSHD systems in place and sustainable practices guiding the future, the Gippsland Lakes stand as a shining example of how innovation and environmental care can go hand in hand.