I'm installing a residential drip irrigation system for my home. I understand the need for backflow prevention and plan on using anti siphon valves. I have one area that is a full story higher than where I plan to install my valves and the rest of the system which is on our back deck. While this area will be fed from a dedicated valve -- I would rather not have to install a constant pressure mainline up to the deck to raise the valve the required 6" above the highest emitter.
In this case, could I add a second valve to the poly tubing at a highpoint to prevent backflow? If so, which kind(s) would be appropriate?