Fremantle Inner Harbour dredging

Fremantle Ports commenced maintenance dredging of the Inner Harbour on 15 April 2024 to remove sediments that have accumulated since capital dredging was undertaken in 2010. The works are estimated to go on for ten days.

A total dredge volume of 80,000m3 is proposed to be removed over five years, with 60,000m3 of sediments planned to be removed in 2024, and then approximately 5,000m3 of sediments annually from 2025-29. It is proposed that dredged sediments will be disposed of at the Gage Roads offshore disposal site utilised in the 2010 dredging project.

The dredging will allow safe access for ships into the Inner Harbour, and ensure the berths remain deep enough for larger container vessels.

Fremantle Ports has engaged marine consultants to undertake environmental investigations and assessments including sediment sampling, plume modelling, seagrass mapping, and to develop an environmental management plan including monitoring. Dredging in 2024 is planned to be undertaken in autumn to reduce the impacts on seagrass as their dormancy stage occurs then because of a reduction of sunlight. Modelling predicts plumes will be limited to upstream and the mouth of the Swan River during operations, with turbidity (cloudy water) similar to that experienced during winter rainfall events.

The dredging project marks the first opportunity for Fremantle Ports to use three newly-trained Indigenous Marine Rangers. One of the rangers will conduct marine monitoring on a science vessel before, during and after the dredging operations and the other two rangers underwent training as marine species observers and will be positioned on the dredge. Marine species observation is a highly regarded skill in the marine environmental industry and will provide valuable ongoing work opportunities for the rangers.

The details of the project including the Dredging Environmental Management Plan and results of monitoring will be communicated on the Fremantle Ports’ website.