I tried controlling the water flow with a solenoid valve this weekend with mixed results. I wired it to a 12V battery pack via a push button switch I had lying around.
The valve has 1/4 inch BSP inlet and outlet fittings, yet my pipe and nozzle are 3/8 inch BSP. I had to get some adapters to reduce for then expand from the valve. They can be seen as the silver fittings on each side of the solenoid valve.
The valve worked perfectly. I was able to rapidly turn the flow on and off. But due to the restriction from 3/8 to 1/4 at the valve inlet, and expansion from 1/4 to 3/8 at the outlet, plus flow resistance from the valve innards there was too much pressure reduction and the range was reduced to about 28ft.
I'm going to try a new nozzle turned to fit directly onto the 1/4 inch valve outlet next. Hopefully this will reduce the pressure drop.