During my time as an Assembly Member I was invited to see the work done during the night and at weekends by both Tubelines and Metronet. Work at night during the week has to be meticulously planned and organised. As soon as all passengers have left around half past midnight, teams of workers go down carrying all their tools. As soon as current is switched off and verified safe they can start work. They have to finish and bring all tools back to the surface by 4.00am to 4.30am before current is switched back on and the cleaners begin their shift. Gloves need to be worn because in places there are rats down there which pee on everything so there can be a danger of contracting Weil’s disease. The atmosphere in the tunnels is black and dusty and most unpleasant.

Most of the time consuming work, such as replacing worn track, can only be done at weekends. I was surprised at just how many people were down there during the Saturday and Sunday that I visited, working in a fine spray of water to damp down the dust.