Maximum y value with corrosponding x value from odesolve result

I drew up a mathcad sheet that plots a y against x from a odesolve function. For this i have a range of x that gives a number of y(x)'s and plots a curve for me. (this is for a flow profile in a open channel, with lateral inflow)

My problem currently is that i get a list of y(x) values after i done the odesolve function, but how do i now get the maximum value of the ones that he spat out, without having to sieve through them manually? i tried the f=max(y) or max(y(x)) but to no avail...

Can someone please advise me on what to do here?

Kind Regards

Jean-Pierre