This video was located at the video website LiveLeak.com, under the title: Monster Seen In Sewer caught On Camera During Survey. I poked around further and found a slightly better video on youtube with slow motion of the interesting parts.
Searching for further information I find :North west water company United Utilities (England) is appealing for help after sightings of an unusual-looking animal in the sewer network.
The creature, which one worker described as being 'far too big for a rat, standing upright on strong back legs' has been spotted in sewers in the north west in recent weeks.
The water company has today published CCTV footage of the creature, filmed by sewer engineers during a pipe survey, in the hope that the public can help to provide answers.
Update April 5, 2011
Unfortunately, this has turned out to be an April Fools joke. I always found April fools to be an irritating holiday. It was fun for awhile anyway. http://www.unitedutilities.com/monstersightings