FREMANTLE PORTS is planning to dredge the Inner Harbour next year to remove sediments that have built up since it was last deepened in 2010.
It’ll be a greatly reduced project from last time, with just 2.6 per cent of the volume of sediments that were removed in 2010 planned to be taken away during the maintenance dredging that will run from 2024-29.
But that still equates to a sizeable 80,000 cubic metres of silt and whatever gets thrown over the side of freighters, with 60,000 cubic metres going next year and later clean-ups.
Ports says that the maintenance will make it safer for ships to navigate Fremantle’s harbour, while also allowing the bigger freighters to berth.
Ports will use the same Gage Roads offshore disposal site it did last time and says it will be timed from April to August when seagrasses in the area will be dormant.
Consultants have modelled the dredging and say it’ll be a low risk to the environment, including only minor plumes slightly upstream and around the mouth of the Swan River which will have around the same impact as a big rainfall during winter.