Bundaberg Burnett River Dredging

Scope of Works

Severe flooding impacted the Burnett River. As a result, the navigational channel required dredging to restore the depth of the river’s navigational channels adjacent to Kirby’s Wall. A total of 65,700 cubic metres of sand and gravel was removed from the channels and placed behind Kirby’s Wall.

TMR nominated two specific dredge areas:

• Dredge Area A, adjacent and upstream of Kirby’s Wall, required 36,000m3 of material to be removed, and
• Dredge Area B, downstream of Kirby’s Wall with almost 30,000m3.

Dredging to a maximum depth of 2.3m below LAT was required in both channel areas.

The dredged material was required to be placed behind Kirby’s Wall to fill in the area between the river bank and the rock wall. The spreader barge spread the material evenly to a height below +0.3 LAT.

Equipment Used

• Dredge & Booster – The 450mm cutter suction dredge the Nu Endeavour was used for this project. In addition, a booster pump and pontoon were connected directly to the rear of the dredge to extend its pumping capability to reach the required distances to the disposal area (up to 1,700m).
• Spreader Barge – We undertook the replenishment works behind Kirby’s Wall with a spreader barge with a three-wire anchoring system. The three-wire system allowed the spreader barge to winch across the fill area while discharged material. In addition, to ensure anchor lines didn’t come into contact with the top of the wall and cause damage, floating pontoons were employed adjacent to Kirby’s Wall.
• Support Vessels – Other supports vessels included: a Workboat, the MV Tramp; Fuel Barge; Anchor Barge and several smaller tender vessels.