The people who operate sewers need to know if any leaks develop
There are two types of sewer in Britain, the storm type and the so-called 'foul' type, which is the one that carries all the jobbies. Contrary to every computer game you've ever played, most of these sewers are very narrow in diameter, like six inches across or so.

You may have noticed that the square manhole covers you get in every street are roughly 100 metres apart - this is so that the insides of the tube can be inspected. Inspected how, you might ask?

Well, as a weak and naive 19-year-old I got a temporary job with a company who have a contract to record video of the inside of the sewer tubes and send it off to however maintains them so that they can check for any structural defects.

The way this is done is quite long winded. Two adjacent manhole covers are lifted, and then a very long, rigid but bendy cable is shoved into one end of the sewer pipe and pushed with great physical effort the 100m to the next manhole. The man at the other end has a tripod set up over the second manhole which has a winch attached to it. When the rigid cable appears, he attaches the cable from his winch to the first cable.

The person at the first manhole then pulls the rigid cable all the way back through, which of course has the effect of pulling the winch cable along with it. When this is all the way through, the rigid cable is disconnected and a camera is attached to the winch cable. The camera has a very thick cable coming from it which powers it and also takes the video feed back to the recording device in the van.

So winch man then slowly and carefully winches the camera all the way through the length of sewer, until such time as the camera has gone all the way through. Then the camera is pulled back by hand, and the manhole covers are replaced.

As I said I was pretty damn feeble, and the effort involved in this was rather too much for me, so I felt very embarrassed that the muscly, ex-army man had to take over frequently whilst I sobbed like Cedric the Sissy.

As you can imagine, this was not a pleasant job in any sense of the word. In addition to the groping-through-shit nature of the job, Mr Ex-Army's conversation seemed to stretch no further than complaining extensively about the Pakis, and so I didn't go back for a second day.
(Eukanuba, Sat 18 Jan 2014, 13:17, Reply)