Two very enthusiastic and loyal BT workers showed me the three-storey drop they had to descend to fix phone lines on my road; at the bottom was water. According to one of them, there's a route at Tottenham Court Road that runs beneath the Underground; he said it's known as the German line because it was built by prisoners of war, though I'm not sure if the chronology tallies on this. If anyone knows any better do let me know.
The repairmen were here as a length of cable had been stolen from along the whole road, affecting 1,600 homes. I was told cable can fetch £5,000 a tonne and, in this case, the thieves had probably made away with £7,500-worth.