Free trams overcrowding Melb: Lord Mayor

There are fears Melbourne's new free tram zone is causing overcrowding on the CBD tram network.

Public Transport Victoria says the number of CBD tram users rose by 22 per cent in March, compared to the same time last year while outside the CBD the number was up by just 2.8 per cent.

Lord Mayor Robert Doyle told The Herald Sun some stops that were coping with capacity before the zone was introduced in January were now beyond capacity.