Travellers on the Tube\'s busiest line will face a series of weekend closures due to upgrade work starting later this year, it was announced today. But Transport for London (TfL) said the disruption to the Underground\'s Northern Line would be far less than originally planned under the Tube\'s now-defunct Public Private Partnership (PPP) scheme. PPP company Tube Lines had proposed 65 weekend closures on the line, many of which would have seen the whole line, or large parts of it, shut down. Instead, there will now be just eight full-line weekend closures - five in 2013 and three in 2014. There will also be eight weekends where shorter sections of the line will be closed as well as six part-closures during Easter and Christmas holiday periods. TfL also said there will be none of the originally-planned early-evening closures, although the northern branches of the line will start slightly late on Sundays. Overall, there will be 60% less disruption than under the original plan. The work, due to be completed in 2014, will increase capacity by 20% and reduce journey times by around 18%. The Northern line is used by more than 900,000 passengers each day.