Crikey! With all the evidence of rising sea levels, today we look (with a little help) at London’s deepest station platforms.

Underground passengers want to know: ‘How deep are the tunnels?’ with the supplementary question: ‘Which is the deepest line or station?’

Checking these questions out on the web and the answer to where you might need wellingtons seems very easy.

Hampstead lies nearly 200ft below the heath and, should the lifts break down, has 320 stairs going down to it, with the deepest line being the Northern Line which runs to that station.

But with climate change, we really need to know which stations and platforms are below sea level.

Hampstead is only so deep because it’s underneath a massive hill. This doesn’t answer our question about flooding unless a massive tsunami hits London.

As you might expect our answer lies somewhere near the Thames, which is at sea level, pedants might argue that would depend on tidal flows, the phases of the moon and how might rain have fallen.

London Bridge comes out on top. Its platforms are, on average a whopping 72ft below sea level, followed by Southwark at 69ft, Elephant & Castle at 59ft, and Pimlico trailing at 52ft below sea level.

But if you’re after the deepest individual platforms it’s different again. Waterloo’s Jubilee Line platforms are the deepest platforms at over 85ft below sea level, closely followed by Westminster’s Jubilee platforms at 82ft and London Bridge’s Jubilee platforms at 75ft below sea level.

Daniel Silva, who clearly has time on his hands, has produced a series of diagrams which illustrate our deepest stations.

So I hear you asking: Where is the deepest cab rank? No data appears to be available, but my guess is outside the Globe Theatre, feet from Bankside Pier and the Thames Clipper service.