Tales of the Underworld

Blake Morrison at the Guardian gives a first-hand account of the London underworld - the sewer system.

For those who are concerned about this sort of thing, you get exactly the kind of offensive language you would expect in an article about sewers, and no more. Consider yourself advised.

But the real enemies are the fast-food outlets. [...] Where a slug of fat is several cubic metres in volume, pressure-jetting isn't enough to clear it - they have to use pick-axes instead.

The presiding tone of the sewer-men is exasperation: they can't believe the ignorance, profligacy and dirtiness of those who live above ground.

This made me wonder: how much damage do we do to our own environment without realizing it? My mother always told me not to pour grease down the kitchen sink, but when I was little I didn't know any alternatives. What else don't we know about the ground under our feet?