The Port of Melbourne Corporation says the project is on budget and on schedule, and major dredging would be completed by August 31.

Shipping channels have been deepened from 11.6metres to 14metres.

Port chief executive Stephen Bradford said: "We are on course to deliver this project within full compliance of environmental limits.

"We have seen no evidence to suggest dredging has impacted on [Port Phillip's] ecological health. From all accounts, the beaches are in good shape and there have been no significant effects on tides, currents and marine life."

"Minor" dredging in the Yarra River and work on navigation aids, berths and services protection was scheduled for completion by year's end.