Most of the notches seem to be missing, however, and neither Geoffrey nor Eva felt like finding out how much is below the water level the obvious way! At a guess, however, the “9” on the top notch that remains visible means 1.9 metres (6’3″) above the stream bed.
Where is this gauge, and what’s its function? Looks fascinating.
It is just to the east of the Field Way bridge. Function may be to show how flooded the stream is during those downpours.