Drip Irrigation times seem really long

My irrigation system is a little unusual in that it is almost all drip irrigation. Most of it is grass and front flowerbeds with mostly shrubs. I am not certain about our soil type other than the majority of it is clay. The system recommends 1 hour and 9 mins for several of my zones. In the past we would get standing water and runoff if we ran it for much past 25 mins. Can the 1 hour 9 mins be correct?

I am doing a monthly flex schedule. We are limited to watering twice a week on specific days. Most are slight to moderate slopes with lots of shade. It seems like I would be watering a lot more with this and wasting a lot of water.

I have drip zones that are scheduled to run for 10 mins and I have drip zones that are scheduled for an hour, also at different frequencies. There is no one answer. It all depends on how much water your emitters are putting down and what types of plants you have.

Hi @pgarriso1. I’m curious how you get runoff with drip? True drip is supposed to be slow enough that it will soak before run-off, and the longer you run the deeper the soak.

Like @beranes so much will depend on your circumstances. Where do you live, what soil type do you have, how mature is your foliage, what type is it and what is the flow of the drip heads and how many do you have per plant. In my case I have some very mature trees and shrubs that I run for hours on drip, but relatively infrequently. For some newer plants and planters I’ll run for 10s of minutes.

At a certain point, the ground becomes saturated, and because of the slope, the water runs off. I read another comment where the emitters were putting out water faster than the clay soil could absorb it. I am going to lower the time to under an hour and use a manual cycle and soak. See if that gives it time to absorb into the ground. We will see how it does. Sounds like might take a bit to tune this in. Maybe I was just under watering this whole time?

It is mostly Saint Augustine grass and two mature oak trees.

@pgarriso1 I’m a bit confused. Is the runoff on the drip or grass, and what type of gallons-per-hour do you have on each, or is the grass not on drip?

There is a lot of confusing and contradictory information here. Let’s start from the top and just focus on those zones that have runoff. Are these zones:

  1. All sprinkler/all drip/mixed?
  2. lawn/trees/flowers/mixed? If mixed, what is mixed with what?
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I am getting runoff from the grass zones that are on a Drip system. This was with my old control that would run after rains. So the ground would be pretty saturated already. Not certain the gallons-per-hour. My guess is .7 to .9. Not bad runoff but only was running 25 mins then. It would pool in some areas an run off onto the sidewalk.

The zones are drip. Saint Augustine grass lawn with on mature oak tree… I notice it more when we have had rainfall and the ground is already fairly wet. I would run the zone for 25 mins and would get pooling and runoff (due to slight slope) on to the side walk.

Just to clarify: you water your lawn with a drip? Is it one of those subsurface systems?

Yes that is correct. It was put in during a drought. It is subsurface.

  1. can you post a snapshot of this zone’s Advanced screen?
  2. I’m assuming you set the soil type to clay
  3. Have you adjusted Nozzle Inches per Hour to match how much water you subsurface system is applying?

They are still at the default. How do I determine in. per hour? Available water? etc…

Here is the snapshot of one of the zones.

there is a formula floating around these forums. Let me see if I can find it.

But generally, you can estimate the total volume of water applied per hour either from the specs of your system (flow rate of each emitter multiplied by the number of emitters) or by measuring how much water was dispensed using the water meter and converting that to gal/hr. Once you have your gal/hr number, convert that to cubic inches per hour, then divide by the total area covered by your subsurface installation. This should give you in/hr.

To find your available water, and other pertinent soil factors take a look at this post.

the formula is at the bottom of this thread: Struggling to get settings right for drip - Schedules & Zones - Rachio Community