THE Metropolitan line has had the biggest rise in delays on the London Underground, a new report shows.

It follows a Transport for London (TfL) apology to passengers after a series of signal failures wreaked havoc during rush hour last week.

Delays on the Tube network overall have risen by 20 per cent between 2009/10 and 2010/11, the London Assembly study revealed.

Met line delays were up 53 per cent from 1.8 million to 2.7 million lost customer hours last year. This was the highest increase in delays of all eleven lines in the 12-month period.

The 50-year-old A-Stock trains on the line are being replaced but the new S-Stock carriages have incurred teething problems.

A contract to replace signals was put back several years after the collapse of the private maintenance firm Metronet in 2008. The work will not now be complete until 2018.

One Eastcote resident described his "worst Tube experience ever" on the Met line last Tuesday, September 6. Chris Anderson, of Mount Park Road, left his office soon after 5pm but didn't get home until after 9pm.

He told the Gazette: "In the eight years I have been using the Met line and 25 years of using the Underground this was the worst experience I have ever had.

"I got to Aldgate at 5.30pm and was told there was a signal failure in the Finchley Road area. We were ushered on to a Circle line train to Baker Street. I have never seen so much overcrowding, they closed the gates to allow people to go under to the Jubilee and Bakerloo lines.

"I was still there at 7.15pm. It was very serious. There were further multiple signal failures at Wembley Park, when the train did come the driver didn't seem to know what was happening. It was constantly stopping.

"To make it all worse there was an England football match on. When I got back to Eastcote it had been four hours since I left work."

Howard Collins, London Underground's chief operating officer, apologised. He said: "During torrential rain in the Finchley Road area a local drainage system failed, causing a build up of water to rail level and leading to a signalling failure.

"The Metropolitan line was part-suspended between Aldgate and Wembley Park and staff worked flat-out to restore the service. We apologise for the disruption caused and are working to improve drainage in the area."