4 ms·
Fascinating post as always from Ian. My dad used to work for the underground and hearing him talk about the challenges of the engineering down there was always
by noneeeed 5y ago
Fascinating post as always from Ian.
My dad used to work for the underground and hearing him talk about the challenges of the engineering down there was always fascinating. This is especially true for the deep tunnels and the older parts of the network. Trying to keep the whole network dry, when you are dealing with brickwork that might be 100 or more years old, in a water table that has risen a lot following the end of heavy industry in London sounded like a particularly tricky issue.
Add in the constrained space and often very limited access on the deep lines and you can understand why it can take so long to do some projects, and why things like longer operating hours might sound nice but have significant knock-on effects.
- m4rtink 5y agoHow did the heavy industry influence the water table ? I guess they used a lot of water from wells, lowering the water table ?
- noneeeed 5y agoYep, basically. Water use is one of those hidden effects of a lot of industrial processes, whether it's used as a coolant or a solvant for processes it often takes a ridiculous amount to produce many goods. In the past the water would be pumped up from boreholes (London sits on an artesian basin), and was then discharged into the Thames (directly or through the waste water system). This happens a lot less now, because of both a reduction in the amount of industry and improvements in efficiency, so the water table has risen, which means that TfL have to pump out a lot more water than they had to decades ago.
- m4rtink 5y agoOh, interesting! I guess the local hydrology here in Czech Republic is different as AFAIK all the old industry around here used to take (a lot!) of water from the local rivers, artificial mill water channels, etc. Haven't heard about them ever using wells in any significant way.
- deleted 5y ago[deleted]