Have a 5 for both pics! I used to visit the Chew Valley, as teenager, from Huddersfield, but I don't remember anything quite as surreal as this!

Thanks Dave, the stainless steel fence around the bellmouth/plughole was put up a couple of years ago to prevent debris from going down the hole, possibly also as a fore thought as they intend to install a water turbine to the river feed pipe which exits at the same place. It does add a surreal feel to the Dovestones Reservoir :)

Brillinat photo Craig!