Getting more water

I use a well with a 6 gpm return. I have 13 zones with 4 heads per zone. All heads have 1.5 gpm nozzle. Can I increase the nozzle size or should it match my 6 gpm return on the well?

I am trying to get more water put down. I have sandy loam and my zone only puts out .29 inches per hour. Not neatly enough. So I have to water forever. Now since no rain in weeks my lawn is brown in spots.

1.5gpM? That is not a horrible flow for a sprinkler nozzle, and that maxes out your 6gpm well. Not sure how you are going to put down more water based on what your well is putting out.

I thought so. My zones only put out .29 inches per hour. So I need to water a lot I guess.

That precipitation rate confirmed with a catch cup test? .29" seems a bit low to be honest…

Actually, I did a test on a zone last night. Please see attached test.
Catch Cup.pdf (255.2 KB)

Wow, so you are actually even lower than the .29.

Not that it is going to help a ton to lower your watering durations, but I might play with the throw and arc of some of those sprinklers and see if you can help that uniformity.

Yes, that zone is the last one 13. It covers the side of the driveway which is a short area. I am going to do other tests on the other zones that cover more area. But I fear my results will be similar. Question though when I do the other tests do i run more than one zone if some of the adjoining zone covers the area in the main zone.

For example: Zone 2, also has overlap coverage from Zone 3 etc. So when testing Zone 2 I should then run Zone 3 so if one of the heads adds water to Zone 2 to correctly display the amount?

If there is overlapping, I think it is a good idea to run the adjacent zones.

Ok will give it a shot tonight

Ok horrible results. Down to .11. So if I have a 6 gpm well recovery and I don’t want to put out more than 6. Would a booster pump help? Or what about if I have 4 heads in a zone currently. What about reducing that to 1 head. I would be able to spray with a larger nozzle so putting down more water right?

I am desperate.

A booster pump is only going to help build pressure, which i don’t think you need. To build volume. You need a bigger pump down in the hole, if your ground can accommodate. What type of well do you have? 6.0 gpm really is pretty low. Do you have a pressure tank on the system?

I have a drilled well 260 feet. They hit water at 60 feet at 6 gpm. They continued further but the water stayed the same. So I do have a reservoir. My well pump is 1/2 hp. I do have a 22 gallon pressure tank bladder on the system.

I was going to do a flow test using the pressure tank method just to make sure I was getting 6 gpm. I am hoping for more. That way I can change the nozzles

I use Rainbird 5000 heads. Is there a better head out there I could use?

Why does Hunter appear to put out more water than Rainbird?
Hunter.pdf (374.9 KB)

So your well + system has some volume of water in reserve, and there’s some flow rate into the well that seems to be at least 6gpm. So you could pull 7 or even 10gpm per minute (limited by your pump and plumbing) out for a short time until you deplete the reserve, then you will only get out whatever that actual rate is on the well.
200ft of 4" well pipe would hold 130gallons of reserve water.
6" would hold 293gallons.

Assuming your well rate is 6gpm, and you consume 8gpm, that 293gallons will last 146min, then your well is going to suck air or whatever they do when they run low. I also imagine your flow rate and/or pressure will steadily reduce as that water level drops in the well, as you are gaining 200ft of head pressure (86PSI) your pump has to overcome.

So I probably should not do anything. I don’t want to damage my pump. That would only add to my headaches.

I’ll say I don’t explicitly know the nuances of well systems, I’m just familiar with general plumbing and have an engineering background.

I would also add that personally, I thought an hour of runtime on a zone was stupid long, but it doesn’t really matter if it’s 20min or 90min when it’s happening at 5am. Just get the right net amount on your plants.

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Every manufacturer has different specs on their sprinklers and nozzles. That is why it is important to dial in your settings in Rachio. I think Rachio did a pretty good job on the default settings to find the average precipitation rate (inches per hour) between a number of manufacturers, but depending on what you have, you could be on the extreme high or low side for that particular nozzle type, causing over or under watering.

At the end of the day like @RPostWVU said, your grass needs the water it needs. Whether it take you 5 minutes to apply or 5 hours to apply. It sucks that you have 13 zones to run through since you can only accommodate 6.0gpm, but it is what it is. You do have a slight buffer with your pressure tank, but 22 gallon is too small IMHO, leaving you with virtually no drawdown. Growing up, our well put out way more than 6pgm, and we had an 85 gallon pressure tank.

I guess I really need to do a flow test. I have been running this sprinkler system for 15 years and never had a problem with my well pump. But my current setup if everything watered would be 11 hrs 17 minutes.

I guess I will just have to deal with what I got.

I mean, there are options. It just comes down to how far do you want to go, and how much you want to spend. A much larger pressure tank will allow for a lot more drawdown, but could be a bit spendy…

Would drawdown allow me to go to bigger nozzles? What size tank would you recommend?