4 Lines Modernisation Project

The Project

Once complete the historic Four Lines Modernisation (4LM) project will have updated London Underground’s most important railway lines, accounting for 40% of the network’s traffic.

4LM is a project to upgrade the signalling systems of four of London Underground’s most important railway lines: Circle, District, Hammersmith & City and Metropolitan. When it’s complete, 4LM will boost the number of trains to 32 every hour. Peak passenger capacity will be increased by an overall average of 33%, with dramatic improvements of 65% on the Circle and Hammersmith & City lines. It is the world’s biggest project of it’s kind.

The Requirement

In May 2016, Advance TRS were approached by our client with an urgent requirement to create a staffing partnership to resource their 4LM works. The works were set out in 3 clear stages. In addition to the resourcing requirements for each stage, considerable compliance procedures were required and put in place to ensure all workers are fully compliant to London Underground regulations.

  1. Mobilise 80 safety critical staff for a weekend possession. Full recruitment delivery responsibility for 80 workers | 4 week lead in | Identified and primed a talent pool of 150 possible staff | 100% fill rate | Full compliance and audit trail | 100% retention for next possession (no failures or rejections).
  2. Downsize workforce from 80 to 30 in between major possessions. Whilst reducing the workforce it was essential to keep key skill sets available for stage 3 keeping staff engaged for the next phase of remobilisation.
  3. Remobilise up to current levels of approx 200 workers. Maintaining a high retention rate and 100% fill rate, Advance TRS currently supply approx. 200 staff working on our clients 4LM Package 1 works.


Compliance, Health, and Safety As an experienced provider of safety critical engineers, we employ a thorough compliance check on all candidates. This in-depth procedure includes right to work checks, reference checks, qualifications, certifications checks, medicals, drug and alcohol tests.

Our Solution

Our modular project capability options system allowed us to design a bespoke program with all the necessary elements and resources to produce success and not include superfluous services.

The initial consultation ensured that the correct delivery resources were deployed to produce the required outcome. By taking a fast but detailed Project Staffing Needs Analysis before implementing a bespoke solution with the following structure and dynamics, we ensured effective delivery for the first possession, with a 100% fill & retention rates for the next possession and ongoing work program.