After looking it seems no one else has been down this culvert and connecting drains so by the power vested in me i now pronounce you Jamrag culvert and drain!
I needed to go to Morrisons for a baccy so decided to pop down the culvert that runs next to it, after an eight foot climb down embankment ( I took rope ) I was face to face with the first drain which I decided not to head down as I was clearly visible from the car park
It's only a small culvert and has a distinct lack of features.
Almost at the end of the culvert there was a drain, it was large enough for me to crawl down so before I had thought about it I was about 5 foot inside.
This is where the smell of crap hit me and the jamrag was hanging taunting me with it's filth
At the end there was a sluice gate that I'm glad was closed
I though I had a way out but the cover wouldn't budge
I ended up heading back up the river to the rope, I decided to leave the first drain until I forget the smell of the other drain.