Buses are replacing trains along the Belgrave, Lilydale, Glen Waverley and Alamein train lines while signalling is being upgraded between November 30 until Tuesday.

The works have knocked out lines between Camberwell and Parliament stations for passengers on the Belgrave, Lilydale and Alamein lines, and between Darling and Richmond stations for passengers on the Glen Waverley line.

The Glen Waverley line usually runs trains every seven minutes to the city between 7.30am and 8.30am. A Public Transport Victoria timetable shows buses depart every 10 minutes from Darling to Caulfield between 5am to 6am. There is no information available for the peak period from 6am to 9am.

At Camberwell station, trains stop every six minutes between 7.30am and 8.30am on a Monday and Tuesday. A PTV timetable shows two buses are scheduled every eight minutes in the morning peak period during the signalling works.

Buses carry 70 passengers, while trains have a capacity of 900. If the train is full, it would require 13 buses to ferry one load of train commuters.

Commuters have been quick to complain, claiming there is only one bus for every train.

"Seriously WTF @metrotrains!? Closing 2 train lines in peak and replacing with one bus is an absolute joke. Every time I think that Melbourne public transport works I need to remember you run the service," Alastair McCausland said on Twitter.

Metro is running 142 buses across the four lines during the works, 112 from Camberwell and 30 from Darling.

"We apologise to passengers whose normal travel time was extended due to essential signalling upgrades," spokeswoman Sammie Black said.

Daniel Bowen, spokesman for the Public Transport Users Association, said about 10 buses were needed to replace a single train and the delays on the network had been an indication of poor planning.

"Upgrades are always tricky to manage," he said.

"But there seems to have been some serious planning issues with this particular project."

Peak-hour trains often run at or close to capacity, Mr Bowen said.

Trying to replace such high density transportation with buses, trams and cars is going to cause "quite a mess", he said.

Frustrated train commuters have been forced to wait in long queues for buses at Camberwell and Richmond stations as a result. For some, it's added an extra hour to their morning commute.

Metro Trains denied that there was any extra build up of passengers at Richmond Station on Monday morning.

Commuters, however, were quick to pick up on the imbalance between trains and the replacement buses.

Meanwhile, trams in Camberwell and Malvern have rapidly filled to capacity as thousands of people squeeze onto older A and B class trams that carry 110 and 254 passengers respectively.

"People will need to be patient," Mr Bowen said.

"But you'd hope the authorities learn some lessons from the last few days and make better plans next time."

Further comment is being sought from Yarra Trams.