I feel I may have opened pandoras box by even mentioning them! Quarter turn solenoid valves are essentially automated ball valves. The benefit of them over diaphragm or plunger type valves (like Moomba used) is that when open, they do not impede flow at all. They can be actuated by a number of methods including air (pneumatic) or electricity. Obviously we would want the electric variety for this application.

Now the bad news; I've yet to find a reliable source that sells them for an affordable price! I found one distributor once that had them for $60, but they are no longer in business. I hate to quote prices that are too high, for fear of someone finding a lower source.

Typically they cost between $100-150 for a decent metal body valve that will actually survive being used in a boat. So what does that mean? There is absolutely NO way quarter turn solenoid valves make sense from a dollar and sense perspective. For much less money you could install a single 2000GPH Rule pump for each bag, and have a faster more simplified system. The theoretical maximum amount of water that 3/4" hose can flow at the pressures we're talking about is around 2000GPH, it would be one thing if someone made a 6000GPH (2000GPH x 3 bags) pump that was affordable, but there's nothing out there with that capacity unless it's gasoline powered.

If it was my boat, I would remove the sprinkler valves, replace the Rule pump with some Tsunami's and check valves and be done with it. That's the cheapest, most flexible, fastest and most reliable system you could come up with.