A scientific investigation had found controversial rockfalls during trial dredging of shipping channels near the Rip were “ecologically minor”, Port of Melbourne Corporation announced yesterday.
Chief executive officer Stephen Bradford said the investigation had also found regrowth in the trial dredging area, “and that we can expect this to continue”.
He called the study “the most comprehensive scientific investigation ever conducted” at the entrance to Port Phillip Bay.
The dredging trial late last year angered environmentalists when it led to rockfalls over parts of the bay floor.
Environmentalists claimed the falls damaged sensitive marine life and demonstrated a proposed program to deepen Port Phillip Bay shipping channels was not worth the risk to the environment.
Port of Melbourne Corpora-tion wants to deepen sections of the main shipping channel to allow access to Melbourne for new-generation container ships with deeper hulls.
Project supporters say dredging is critical to thousands of Victorian jobs and the state’s economic prosperity.
Mr Bradford said a 180-page report on the scientific study had provided a “vast amount” of information for the channel deepening project.
The study used a remote-operated vehicle with a camera to inspect the seafloor in the trial dredging area.
“Following on from the field work, this expert scientific study indicates that rockfalls predominantly landed in the shallow regions above 30 metres and is considered ecologically minor and that there was limited change in deeper water,” Mr Bradford said.
“The report shows evidence of subsequent regrowth in the trial dredge area and that we can expect this continue.
“In the past, regrowth has occurred at the entrance (to the bay) after blasting using explosives, which is no longer the practice.”
Mr Bradford said the EPA had commissioned an environmental audit of the report.
He said the audit “identified the need for further monitoring, which the port endorses”.
The port corporation was also carrying out testing on a dredge head to work out a way of minimising rock spills, Mr Bradford said.