When exploring subterranean spaces, there is always the risk of danger. Sewers, are no exception to this rule, gases, disease, feral rodents, angry workers and the potential of flash floods. Most of these can be prevented by utilising common sense, no drains when it rains, taking gas meters, so on so forth, you’ve heard it all before.

However problems can arise from the elements you have no control over, such as the tides. As such, unless your part of the lucky majority who can part the waters like Moses, when the tide comes in, you don’t go in.

London’s sewer system consists of several CSO’s, most of which outfall directly into the thames, outfalls which, as the tide rises, allows the river to backfill and flood the tunnel. This can quickly turn a relatively dry draining experience into something reminiscent of deep sea diving, except with more brown trout. So what do you do when the sewer you want to explore spends 21 hours a day filled to the roof with old man Thames? Give up and go home?

Officially known as the “Charlton Storm Relief Sewer”, ‘This is it’ is the last line of defence for the southern intercepting sewers, serving both the Southern Outfall and High Level No*2. A huge double decker, sloped overflow chamber with twin 10ft horseshoe tunnels running to the thames.

Out of all the sewers in London, this is one of the more riskier places to be. Much like the Greenwich Storm Relief, the window for access is tight, about 2 hours, then you have to swim for the exit. Becoming trapped here, although not life threatening, would leave you spending 12 hours waiting for the tide to recede, something i for one didn’t wish to do. With this in mind, we didn’t hang around for long, dropping in and photographing what we could, paying homage to some of the only ‘official‘ photos available at the time before returning to the surface.