SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

I'm trying to trouble shoot and figure out a plan of attack for my sprinkler system. I live on a decently sized plot of land (.7 acres) with county irrigation. My yard slopes up from the South to the North with the main line feeding in at the bottom (south end) of the property. I have two zones that are fed form a single valve that is connected to my timer/controller, I can manually switch between the two lines at an additional valve box up north on my property, or I can have them both on if I so choose. These two zones are at the top of my property and extend from the west to the east, I'll identify them as zone 5a and 5b from here on. Zone 5a is below zone 5b. With zone 5a on It seems like I have just enough pressure, the rotary sprinklers are a bit weak though. There are 3 rotary sprinklers and I want to say 4 pop up sprayers. Zone 5b is at the northern/highest point of my property and has I believe 6 rotary sprinklers. These sprinklers definitely lack the head pressure they need, as far as my eye can tell.

I also have one other zone that supplies water to the east back of my property, and also has a random sprinkler in the front yard. Well the random sprinkler in the front yard is very weak as well. We will call this zone 3


I haven't ruled out everything, but from the looks of it, it would appear that the change in height from the main line to zone 5 is causing the lack of pressure. I don't know what the elevation change is yet, but I plan on figuring that out soon. I haven't done a full analysis to prove this, but it is my first guess. For zone three I'm not certain if the weak sprinkler is the first or the last sprinkler in the line. I'm not certain what the cause is for its lack of pressure, it may be that there are too many sprinklers on the zone?

All the sprinkler lines appear to be 1" with 3/4 inch T's connecting from the 1 inch to the sprinklers. I didn't install the system but that is what I've noticed so far.

Any suggestions or a plan of attack to deal with this issue. I've looked into getting a booster pump and interlocking the pump starter circuit with the zones that could use the extra pressure. But that appears to be an expensive addition ($500 for a 1/2 HP pump). I'm still learning the ins and outs of sprinkler systems so I don't know if there are any other areas I can look for improving line pressure. Any advice/suggestions would be greatly appreciated.

Thanks!