Drip irrigation failures

Troubleshooting Sprinklers & Irrigation
1

Hey, not a Rachio question specifically but a general drip irrigation question I could use some help on:

My drip irrigation seems to have a high failure rate, meaning drippers slowly reduce their output and then clog. I have 22 stations of drip irrigation across 2 controllers, so it’s not a small amount of drippers. They are a combination of Raindrip pressure compensating drippers and Toro blue stripe drip line. The water is the same water that goes into my house and it isn’t cloudy or anything, but it is slightly hard (calcium).

In the course of 3 years of debugging, I’ve concluded a few things:

  • Zones w/o pressure regulators fail quickly, so contrary to intuition, higher pressure doesn’t result in more output but is, in fact, harmful to the drippers. So I now have 30psi limiters on all zones.

  • 0.5 gph (red) drippers: about 20% are bad out of the box and only last a few months

  • 1.0 gph (black) drippers: about 10% are bad out of the box and the rest last a few years

  • 2.0 gph (green) drippers: about 5% are bad out of the box and they fail the least

  • The drip line (0.5 gph) is highly variable (from a few months to >10 years life expectancy)

Above MTBF estimates are just a guess (the original irrigation system is 20 years old and I’ve owned it 3 years). So I’m starting to favor 1.0 and 2.0 gph drippers, and use multiple per tree so if one fails the tree doesn’t die, but it’s still becoming tiresome.

I’m starting to wonder if, like pressure, sun also plays a role as the longest-lived drip lines are covered. Any thoughts there?

Also I’m starting to wonder if I should just change to a different drip system. IIUC there’s two types:

  • The type I’m using where you deliver moderately high pressure (20-40psi) and use pressure-compensated drippers
  • The type where you do a more restrictive pressure and flow limit upstream, and then basically have “open” drippers (no meaningful regulation)

but my local Ace hardware store only carries Raindrip. Any product suggestions here would also be appreciated as I’m willing to try something different if I just knew where to source the parts.

2

I am planning on all sorts of expansion in the drip area in the next while. At this time, I only have the micro-sprinkler type (drip line spray heads). The are definitely susceptible to UV. It seems I replace about a half dozen every spring. The UV light turns them from a nice dark red to a rather light red and they break from being brittle. I do have pressurized irrigation with fine filters, but still get a few clogged drip heads which can unclog these. For me, it looks like fine organic material. Do you know what yours are clogging with being culinary water? I will be interested to see what suggestions you will get.

3

Wow, nice research!

All my main drip lines are buried 6-8", and runs the parameter of my yard. Spaghetti lines run to the plants from that main. Sun will absolutely affect the drip line, especially if you have vinyl tubing. Poly tubing will hold up a little better since it has better UV endurance, but I still recommend leaving a minimal amount exposed…

My small shrubs all have a single 1gph, larger shrubs will have 2. My trees have 2gph, and depending on size with have anywhere from 2-8 emitters. I’ve had good luck with the Rain Bird pressure compensating emitters that I’ve used since I bought my house 10 years ago. I haven’t had to replace one yet. Note that the color coding on these is different than what you have. 1gph is black, 2gph is red.
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Hard water and deposits can also play a roll in destroying emitters, so if this is a major issue, you can try a cleanable PC emitter, which will still require maintenance, and IMO, if I have to go around and maintain an emitter, I’d rather just throw a new one on there…
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All my drip zones are behind pressure reducing filters similar to this. Only time I’ve ever had issues with clogged emitters was if I had a break somewhere in the line and I managed to get some dirt in the line during the repair.

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