Drip tubing Precipitation Rate- help please!

So I’ve been back and forth with customer service this week and scrolled through these forums looking for an easy way to calculate PR for my extremely long and sub-mulch drip tubing. I know the tubing has 1 gph emitters every 18 inches but my landscape is large and the tubing courses through a few hundred feet of landscape. Can anyone assist in this calculation with straight forward instructions? Love the product but the advanced settings on my drip tubing zones alludes me. Thanks !

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Check this out and see if it helps.


Also check out the ‘IRRIGATION HARDWARE (Drip emitters)’ at the bottom of the 1st post here.

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azdavidr. really appreciate your input on this. The information you have provided to the forum is excellent. I definitely have evenly spaced emitters but Rachio’s calculator for this type of drip assumes the area that is being watered is 1 square foot so I am unsure how to measure the amount of water put down for one square foot over a period of time since I have hundreds of emitters. The water meter measures all of the drip emitters collectively since they are all on the same zone. I have emailed support with this question but if anyone here knows the answer please post it. Thanks again!

Don’t get me started on that area=1 assumption @OrthoDoc. I just don’t see it. Anyway, did you look at that second post “Where to start on Flex Daily” and the final calculator pointed to from wsu ? It seems to cover your scenario.

I tried it for my garden which had evenly spaced emitters and wasn’t crazy about the results, but I don’t remember why. You might give it a shot if you haven’t already. What I ended up doing was that I had a good idea of how long I needed to run my garden every day. Using the GPH for the line and the runtime I wanted, I was able to calculate the total number of gallons I wanted to put out (GPH * runtime in hours). Once I had that I went back to my original calculator and used the total number of gallons to get a PR. Does that make sense ?

And thanks for the kind words!

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