I've always found ventilation shafts fascinating too. Is there one on the Northern Line between Waterloo and Kennington? There's always a rush of air on that stretch especially in the southbound tunnel. Even more interestingly, I believe there is a ventilation shaft somewhere along Fleet Street awaiting its Fleet Line tunnels to run through. As much as I love the JLE I wish we could of had both!
Heard there is a shaft that goes down from Lambeth North station to the Northern Line tunnels below. Is this true?
Yes there are connections at Lambeth North. There’s a gallery and heading leading from the southbound tunnel which emerges in the end of one of the Lambeth North lift landings. Stand there and Northern Line trains can clearly be heard. It’s just about possible to access the Northern Line southbound tunnel from here, albeit via a rickety ladder.
On the northbound there’s a ventilation shaft which comes up in the bottom of a disused Lambeth North lift shaft, but this isn’t suitable for man access. There’s also various cable routes leading to the substation adjacent to Lambeth North station, which is in fact a Northern Line substation and doesn’t supply the Bakerloo.
The rush of air may be something else though. There used to be a construction site at Bethlehem Hospital when the line was built, the shafts of which were back filled once construction was completed. However the pairs of shield chambers remain in place on both northbound and southbound, which normally results in a change in air pressure when trains pass at speed, especially now trains regularly reach 50 mph at that point.
