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Plans to split Northern Line in two move forward another step

Transport for London (TfL) has given a further indication that it will press ahead with fully separating the Northern Line into two by the early-2020s. 

Earlier this year, Andy Bourne, LU head of automatic train control, discussed the success of the Northern Line resignalling work with RTM. He also added that work on preparing for the next Northern Line upgrades, NLU2 and NLU3, could see a complete separation of the line into two to achieve 30 or even 36 trains per hour frequencies. 

Recent papers to TfL’s Finance and Policy Committee said that NLU2, also known as the ‘Northern Line World Class Capacity’ project, will increase the number of trains per hour on the Northern line from 22/26tph (current peak service) to 30tph peak service by 2021. 

Additionally, during the later stages of the 2014-15 Business Planning process, Northern Line Upgrade 3 (NLU3) was included in the budget with additional funding made available for a further six trains and associated stabling and infrastructure works. 

It was stated: “NLU3 will deliver a fully separated Northern Line offering between 33 and 36tph by April 2023.” 

^{(Map by London Reconnections)}

This long-held dream to separate the line, however, has been stymied before by the necessity for extensive remodelling of Camden Town station. The last major attempt to do so collapsed in 2004 amid widespread local and eventually national opposition because it would have meant losing important buildings around the station. But in 2013, TfL unveiled refreshed plans, which would see the station rebuilt for 2024. The station would become a key interchange between the two separated Northern lines.  

A team of architects and engineering companies – John McAslan + Partners, Arup, Costain and Corderoy – have “identified a costed strategy to provide step-free access from street level to all platforms and increase the station capacity by providing a five storey box beneath ground and a new single storey above ground forming the new second station ticket hall”. 

TfL added that its plans to split the Northern Line is dependent upon the prior implementation of the Camden Town Station Congestion Relief scheme for which Transport and Works Act Order approval is expected during autumn 2017. 

As a consequence, the additional trains required for NLU3 beyond those for NLU2 will be specified as contract options post-2017. 

(Body Images. Top: c. London Reconnections. Bottom: c. John McAslan + Partners)