Maintenance dredging works at Altona Safe Harbour entrance channel are about to begin.
Dredging operations will be carried out by a cutter suction dredger, Parks Victoria said.
Dredged material is to be deposited in the adjacent area to the south of the Harbour entrance.
On-water plant, equipment and potential hazards to navigation arising from the works will be marked as per IALA standards.
According to Parks Victoria, mariners are advised to navigate with caution within the vicinity of the works.
Hobsons Bay City Council dredges the harbour annually to ensure a safe depth for boats entering and exiting the boat ramp.
The dredge material is black and odorous for approximately two weeks before it returns to clean sand used to rejuvenate the beaches.