The Werribee train line has recorded the second-highest number of rail service cancellations in Melbourne across a 12-month period, after a faulty wire caused problems with overhead power lines in May.

Data from Public Transport Victoria (PTV) shows that between June last year and May this year, there were 999 trains cancelled on the Werribee line (compared to 480 cancellations within the previous 12 months).

The only metropolitan train line to experience more cancellations than Werribee was the Frankston line, which recorded 1256 cancelled services.

Overall, the PTV performance report showed that during May, Metro Trains delivered 90.4 per cent of all services on time and V/Line delivered 86.4 per cent of all services on time.

PTV chief executive Jeroen Weimar said May was a “challenging month” on Melbourne’s train network, following a “serious overhead power issue” at Laverton Junction, which impacted Werribee line services across four days.

Mr Weimar said an independent review, commissioned by PTV, found the problem was caused by a corrosion on a small part of the overhead power structure, causing the wire to fall. The fallen wire became tangled in a train running through the section, subsequently bringing down a large section of overhead wire.

“We know this unusual incident caused significant disruption to passengers on the Werribee line over four days,” Mr Weimar said.

“As a result, Metro Trains is now replacing all insulator connectors on the Werribee line on top of the existing routine maintenance.”

In addition, buses will replace trains between North Melbourne, Werribee and Williamstown from 11.15pm to the last train on Tuesday, July 23 for works to introduce high capacity metro trains.

Passengers have been advised to allow up to an extra 40 minutes their journey.

See ptv.vic.gov.au or call 1800 800 007 for details.