This, to me, is the problem with reporters today, find a silly question and make a story out of it.
How can anyone monitor evaporation, as that is a function of temperature, time and volume. Which would be dependant on types of sprinkler heads, locations and flow rates of the heads.
How do you monitor someones reticulation leaks?
Oh know I get it, it is someone pushing the cause for licensed bores and meters on everyones bores, now it makes sense.
I don't have one, so not my problem.