GeoGraph - photograph every grid square

I am assuming that this is a sewer pipeline because it is heading straight in the direction of what is marked on the OS 1:10,000 scale map as a water pollution control works. The pipeline runs parallel to SU8892 : High Wycombe: Former railway line to Bourne End, the embankment of which can be seen beyond. The much smaller upper pipe is probably some form of venting facility. The patch of weedless water with the dark green edging in the centre of the picture was bubbling away and I am assuming that this must be a syphon that allows water to pass under the railway embankment. All this is pure speculation!