Hello
We know that the water's kinetic energy upon leaving will be converted into potential energy as it is projected straight up. The maximum height attained by the water is 29.6m.
We know Kinetic Energy is
1/2 * m * v^2
And Potential energy is
m*g*h
Equating,
(m*v^2)/2 = m*g*h
The mass cancels out from each side, making an object's mass irrelevant when its Kinetic and Potential energies are interchanging.
v = sprt(2gh)
v = sqrt(2*9.81*29.6)
v = 24.1 m/s