Apollo wrote:the lower gaps in the steps (like the one visible on the left), where the water used to trickle down, have been reinforced with sheet steel to stop them breaking up if walked on.
This was probably done so that kids could run up and down the steps through the water. I seem to remember seeing them do this at the time of the Garden Festival. Our compensation culture probably wouldn't allow such a thing now in case they tripped and broke something, but I suppose we were less enlightened in those days.