This is the so-called New Cut in Cottenham, Cambridgeshire, that drains the local Fenland and into which numerous smaller drains feed from outlying areas, ultimately the drain itself feeds into The Ouse and on to The Wash.
This photo was taken at lunchtime today after a weekend of torrential rain in the area. Yesterday lunchtime the water was about a metre higher. It usually copes with the Fenland run off from the mainly crop-growing agricultural land around here and I have only ever seen it full to the brim once, although that apparently happens quite often.
However, when they build the new town of Northstowe not much more than a stone’s throw from this drainage system, New Cut will have to absorb the run-off from that land too. I strongly suspect that New Cut and the other interconnected Fenland drains will increasingly spill over. Given that the are farmhouses and quite a few dwellings on at least one bank of some stretches it is no great stretch to assume that houses will be at greater risk of flooding than they are now.
By the way, it’s called New Cut (if I remember rightly the embankment was rebuilt in the 1920s), but the drainage system is rather older, predating even the draining of the Fens. More history here.