I recently finished a project and it included a irr. syst. I am going to try to explain this a simple as I can. If you are facing the front of the house the grade is lower on the right and higher on the left. There are a couple of zones on the left side of the drive and 1 zone on the right(this zone has only 2 heads). What is happening is when the system shuts off, the 2 heads on the right are draining the lines of the whole system. Well, this is causing a big problem(mud etc). Is there any way to prevent this or should I nix the heads on the right all together?