It says on the gate, through which this picture was taken, 'Bradfield Vindmill Water Treatment Works'. It's difficult to say whether vindmill should read windmill because somebody has fired a shotgun at the sign and it bears the scars of several pellet impacts. Either way there's no windmill!
Uploaded to Geograph by Stuart Logan on 8 September 2011
Photo © Stuart Logan, 8 September 2011. Licensed for reuse under this Creative Commons licence