Exact water usage using flow


I don’t know if you work for the company or not, but you are clearly not listening to what a large number of customers have been saying for several months. The controller is perfectly capable of performing these calculations, or sending them to a server which can do so–it is simple arithmetic. To expect your customers to perform these calculations manually or even with the aid of a spreadsheet is ludicrous. Every single drip irrigation emitter that I’ve ever seen measures flow rate in GPM or GPH. No one uses precip. rate. I’ve never heard a clear explanation of why this has not already been implemented, or why precip. rate has such a tenacious hold on Rachio engineering. For states like California, which is in its fourth year of prolonged drought, there has been a huge migration to drip irrigation. The controller also needs to allow direct input of flow rate from reading a water meter. For drip irrigation, there is little change in flow due to changes in pressure, which was an excuse I’d read earlier. Drip is typically pressure regulated down to no more than 25 PSI, and variations in pressure have virtually no effect on flow. I know exactly how much each of my circuits use by reading the meter. Multiplying the number of emitters times the emitter flow rate gives a pretty good approximation as well.

Until this flaw is fixed, I won’t be recommending the Rachio to our water department, or any of my clients. I really don’t know what the problem is, and I’m growing very tired and frustrated with the standard response of ‘well, here’s how you calculate that!’. Is this an intelligent controller or not? If it is, it should be doing any calculations of this type. I’m wondering if the product decisions makers actually read this forum. If so, are you getting the message?


@control4reak, yes, the PR rate can be directly entered into the app via the custom nozzle setup page.

@MumblingFumbler, good to hear from you again. I do work for Rachio (head of support) with prior experience in irrigation & landscape management. Please know we are listening and understand your frustration. We are a small team, managing multiple development priorities with limited resources. This feature (and others) are on our backlog to be built as soon as we can with the underlying goal to make everything as simple as possible for the end user.

This is true in most professional installations, however a consumer should be mindful that not all emitters will always have the same flow rate. Just as not all sprinkler heads will have the same flow rate. This can vary on application and site conditions.

We’re sorry to hear you won’t be recommending the Iro until this feature is added. The Iro is a very intelligent controller. I’d be happy to send or post our WaterSense or SWAT test results for reference. Out of curiosity, is there another controller that has this feature designed to your expectation?

Yes, we read every thread and post.

Best, Emil


Where are you at with implementing a GPM?


@kerbelangr, in regards to implementing a GPM on the custom nozzle feature, this is currently in our backlog. Unfortunately I cannot disclose possible timeframes on a release date as we don’t want to set false expectations as to when this will be developed until we are ready to release it.

In the mean time, I’d recommend using the equation in this support article to calculate your precip rate(s).

Let me know if you need any help crunching the numbers.

Best, Emil


I don’t think anyone wants a GPM setting for nozzles/heads but rather for zones. That way we can know exactly how much water we use in our irrigation system.

This would be very useful for conservation, especially those of us who are charged drought surcharges based off total gallons of water used per month…


@basher519, sounds like you would like to be able to set a monthly allowance from which the Iro could water up to? If I may ask, how many gallons are you allowed to use per month? Does this change by month?


Hey Emil, thanks for the quick reply. I have the numbers at home and I’ll be able to check then.

But I think we’re making this more confusing than it needs to be.

Seems like everyone just wants to know how many gallons Iro has used. And the most exact way would be an input for GPM/zone.


@basher519, understood. We’ll brainstorm how to make this easier. All ideas are welcomed and appreciated. We want to make it as simple as possible.


It seems to me, as one who is setting up a drip irrigation system comprised of various types of emitters, it would be great to be able to specify more than one emitter type and the quantity of emitters in each zone.

For me, the actual area of the landscaping isn’t relevant because only specific plants within the area are actually being watered. Thus in one zone of drought tolerant plants I have some emitters that put out 1 gallon per hour and others that put out 2. I know the exact number of each.

However, while I can set a watering schedule based on recommendations for gallons per plant per session it doesn’t result in accurate calculations of gallons used.

I would love to figure out how to make it reflect how much water is actually being used.


@rickandersonaia, are these all low flow emitters? i.e. micro spray & drip emitters. Or are they a mix of high flow emitters? i.e. bubbler & soaker hose

Sounds like your drip lines were designed properly. A drip line should be designed with the water requirements of the plants in mind if the vegetation is mixed; i.e. trees, shrubs and perennials.

Mixed vegetation and nozzles makes scheduling difficult as the Iro uses the precip rate of the nozzle and the vegetation type to calculate the run time of each zone. Assuming these are mixed, you’ll need to override the recommended schedule to match the output of the emitters with the water requirements of the vegetation.

As for calculations, we might be able to accomplish better reporting by calculating the average precipitation rate of all your emitters.

Please keep in mind, the Iro’s reporting is only an estimated usage/savings – for details on how the gallons are calculated, please refer to this support article.

Hope this helps. Happy to help you calculate the average precip rate for the emitters if needed.


Yes, they are all low flow emitters. I was excited about the Rachio because I thought it would optimize my watering based on plant type, emitter count and weather. I see that it probably does that just fine for lawns but for my type of irrigation system and plants it doesn’t do much more than a standard timer. Unless I’m mistaken.

It looks like if I set everything manually then it won’t increase watering on very hot days or decrease watering on cool days, which is what I was expecting.


@rickandersonaia, the Iro will do all of this, but drip zones are difficult to recommend schedules for if the vegetation and/or nozzles are mixed. From a design perspective, the vegetation for each zone should be the same (i.e. root zone depth), then nozzles should be the same type and general output. I’m not certain from the feedback provided if your drip zones are setup like this. Perhaps you could provide some additional detail? Here’s a great post that goes into the details of designing a drip zone/system.

The Iro can still accomplish daily or weekly adjustments to your watering schedules regardless of if Rachio or you determine the base durations. Fixed Schedules water on a static schedule; adjusting watering durations on a weekly basis using historical data and skipping schedules based on weather forecasts. Flex Schedules water only when needed; dynamically adjusting watering days/frequency based on soil moisture needs, calculated using daily ET data.

I hope this helps. Would either scheduling option work for you?


Right now I have a fixed watering schedule with 4 zones. 3 of the zones water shrubs that California classifies as “Waterwise” medium water use for the desert. This means that in November each shrub should receive 1.6 gallons 3x per week. Each shrub has it’s own emitter.

The 4th zone waters the trees. Each tree has its own series of emitters with the citrus trees getting more than the drought tolerant trees.

There is no lawn, there are no annuals.

I would strongly prefer the flex schedule as in the desert (Palm Springs area) watering is significantly different between summer and winter.


@rickandersonaia, ah so in your situation you’d like to be able to set the gallon requirements for each zone and let the Iro calculate the durations necessary? That is very different approach, but an interesting one.

Perfect. This helps assuming each plant is receiving the proper amount of water based on the duration of the watering time (and time of year).

We understand. I think we could work backwards to the durations you’d need to setup on your Flex schedule. I assume you know the the watering requirements on a monthly basis? If you could provide these to me, I’d like to do some testing with them to see if there are any simple work arounds for your configuration.


Our water district publishes guidelines for low water landscaping. I’m getting my values from this page in their guide - http://web.cvwd.org/conservation/lush_book/lush2.html

I’ve attached a screen shot of the watering table - http://screencast.com/t/aOWj3gcFnl


@rickandersonaia, thanks! I’ll review these and be in touch with any possible work arounds.


Just purchased a rachio. My very first observation is that it is very silly to have the “gallons” on the main dashboard and have no decent indication of how it is calculated.

I have read the above thread and see that there currently is no intention of allowing entry of GPM, which I guess is fine given the need or PR for the other calculations anyway.

How about a very simple workaround? On the edit zone page, please add a calculated field (not editable) that shows the GPM for that zone. It can have a link to how to set nozzles/area to make the number accurate. Perhaps even have it in a different color/font/italic if it is the default sq ft of 1000.

Yes, I have found the formula. Yes, I can do the math. But things like the nozzle flow rate are hidden on the web page. With the GPM so hidden and also dependent on the sq ft, its seams wrong to be claiming gallons saved.


We will be doing a Spring release, 2.5, which I hope to incoporate this feature if we have time. Stay tuned! :wink:



For those of you that are trying to figure out your square footage of your zones, Google Maps (http://maps.google.com) will tell you exactly what you’re sq. footage is and then you can use this in your zone settings. I did not see anyone mention it here, so I thought I would throw it out.

  1. Open a web browser and goto http://maps.google.com

  2. Enter the address of the lawn in question.

  3. In the lower left corner of the map click on the “Earth” icon, this will bring up a satellite view of your home.

  4. Zoom in to the appropriate level you desire.

  5. Place your mouse at the point you want to start the measuring process.

  6. Right click on the map and select “Measure Distance” from the menu.

  7. A small box will appear on the bottom of the page telling you to click on the map to trace the path you want to measure.

  8. You can enter as many points as you like. As you go, the distance continues to calculate.

  9. If you complete your measurement at the point you started, you will not get a “Total Area” in both sq. ft and sq. meters.

Hope this helps someone out, it did me!


Very cool, I’d like to incorporate that into our software one day :wink: