Hello, I am using anti-siphon sprinkler valves and I know that I am supposed to place the valves 6 inches above my highest emitter.

My question is, I have one valve that is going to be feeding some drip lines that sit on top of my retaining wall. The wall is 4 feet high so my emitters are not going to be 6 inches lower than the valve that is on ground level. Can I attach a plastic backflow device (like the one in the link) to my sprinkler riser that will supply water to my drip line and have it be okay?

Thanks!

Here is a link that might be useful: backflow device