Pool Fill zones

I know there have been some discussions before about pool fill zones and automating them, but it would be nice if you could choose a vegetation / zone type of “Pool”, enter the dimensions of the pool and calculate the evaporation rate - the formula is straightforward and based on surface area, temperature, pressure, and wind speed:

once you know the evaporation rate you could set up an as needed schedule to keep the pool filled, right? you would also have to know the fill rate but usually a pool fill line has no nozzle on it so it would be based on standard 80 psi city water pressure



Add me to the list. Instead of Pool it’s Koi Pond but the principle is the same. I would advocate for users to be able to add custom types like they can with nozzles. Maybe add a puddle icon for fill type applications.


This would work for bird baths also

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I’d like to voice my interest in this feature.


New customer here, would love to see the feature to fill ponds and pools. I have a medium sized koi pond and was hoping this type of feature would already be present.

Add my name to the list for this!

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Dear Rachio, Please add Pool Fill to the software.

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Yes, please!!! I have a fixed schedule zone just for my pool fill. BUT, it would be great if Rachio could develop a “pool fill” algorithm. Maybe something that adjusts fill time based on user input of pool surface area and total volume plus Rachio’s data for time of year, location, and weather…

I’d love to see a “pool/pond” vegetation type too.

Meanwhile, here’s a work around you can try.

Start by recording how long you need to run your fill valve on a weekly basis… 20 minutes, 34 minutes, whatever.

Then create a Flex schedule for the pool fill zone, and tweak your soil settings until you get a resulting water time the same as your weekly fill time… 20 minutes, 34 minutes, whatever.

Now your system will adjust to seasonal and weather inputs, and basically “scale” because your fill valve is proportional to the pool size.

I just set this up myself with a new pool, so I don’t have much data to tell how well this will work over the course of a full year. But I thought I’d share it for anyone who was looking for a pool fill solution.

Now it won’t calculate the correct amount of water being used, so that’s where we would need an actual “pool zone” calculation… probably just surface area of your pool, and fill rate of your valve.

Hope this helps.

Flex Daily just about gives you want you need already. Crop Coefficient is multiplied by the daily FRET (Forecast Reference EvapoTranspiration) value, plus shade factors, to calculate evaporation per day based on current weather conditions. FRET is a daily or weekly value in inches to indicate how much water evaporates from a standard size open tray, and is the basis for all these irrigation calculations. Using a Crop Coefficient of 1.0 uses the basic FRET value without any correction for crop type, which wouldn’t be necessary here. It wouldn’t include spillage due to splashing or leaks, but should be pretty darn close.

Then, all you’d have to do is measure your water flow to the pool in GPM and pool size. Let’s try an example: Say water flow is 10 GPM, and pool size is 24’ x 40’. From that you can calculate the Nozzle Inches per hour: 24 x 40 = 960 sq ft x 144 = 138,240 sq in = 138,240 cubic inches / 231 = 598.4 gallons per inch of water. So it takes 598.4 / 10 = 59.84, say 60 minutes to raise pool level 1". That is a Nozzle Inches per Hour value of 60/60 = 1.00" per hour. Surprisingly close to a standard sprinkler value (a coincidence, as size of pool and flow rate both change it). So, a set flow rate in this case of 1" per hour and Crop Coefficient of 1.00 should give you about what you need for your pool, on a daily or weekly basis, accounting for the weather. Flex Daily also accounts for the rain, so it’s a no-brainer here.

The only real question then remaining is how often you want it to water, or rather, how low do you want the pool to get before being filled. This is exactly analogous to setting the Soil available water, the crop root depth, and the allowed depletion. Those 3 values multiplied together gives you the amount of water applied at one time. And that value must be /at least/ the amount evaporated per day in hot weather. A value of about 0.5" is pretty good, so if you set root depth to 2, available water to 0.5 and allowed depletion to 50%, that gives you 2 x 0.5 x 0.5 = .5" water. Set the Efficiency to 100% (as you don’t waste any water and it has to be even), and I’m pretty sure you’ve got a Pool Filling Program.

If, over time, it starts lowering, set the efficiency lower. If, over time, it overfills (not because of rain), then increase the Nozzle value a bit. Voila!

This may sound silly, but keeping a pool filled or a yard filled is not really a different problem; it just has different values. If anyone wants to try it and are unsure how to calculate it or proceed, ask and we’ll figure it out.

Oh, and yes, it would be pretty simple for Rachio to add a Pool Program by just doing the above. They’d just have to ask you your pool size and pump GPM, and it’s done. But until then, try the above.

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Rraisley, that is very helpful.

My valve isn’t turning on a pump. It just opens and let’s city water flow through a fill pipe plumbed into the pool. Any idea what kind of flow a typical garden hose has?

I’ll need to read through a couple more times, but like you said, it isn’t much different than filling a yard.

Would still love a preset program, so it “looks” like it is calculating for a pool, rather than a workaround.

Something in my nature doesn’t rest easy using a workaround, lol.

Right, that’s what we would expect.

That depends greatly on the hose size, pressure, etc. but 5 GPM wouldn’t be too far off. You can easily measure it, though, using your water meter and running it for a set period of time.