Zone duration seems too long


#1

My front yard never really greened up this season. I had a company apply the Spring fertilizer and I think it was diluted too much and didn’t help at all. I’ve taken over since early May but the front of my yard is still extremely yellow so I decided to do a catch cup test and see if my nozzle settings were correct.

I setup 9 cups in a 4 head zone (PGP-ADJ with blue no 2 nozzles) and ended up with the following in the catch cups after 20 minutes (all in mL): 15, 25, 25, 30, 50, 30, 10, 15, 45. There was minimal wind when I did the test. So after plugging these into this site (http://irrigationaudit.hydrorain.com/get-started/#/audit), I was given my Precip in/hr (0.31) and efficiency. My efficiency for the front yard ended up at 46% which is awful.

I also have this problem on front right side yard (basically front yard, but on the other side of the driveway). This zone is a 5 head fixed spray head with 15’ nozzles. Here are the results after 10 minutes: 50, 55, 50, 15, 30, 25, 50, 45. The results for this zone are 0.9 in/hr and 50% efficiency (also terrible).

Because of these results, my system wants to run the front yard for 2.5 hours and the side yard for 38 minutes on a Flex Daily setup. This is going to cause issues with my water bill :stuck_out_tongue:

Anyone have any advice or can provide some helpful info so I can get this fixed without costing an arm and a leg?

(Hopefully all my details make sense, writing the post kind of tired/late at night)


#2

I got similarly abysmal efficiency values from my catch cup tests. My backyard rotors run about an hour and I’m running almost every day under current conditions in Arizona heat.

Could you please post your Advanced zone settings numbers, since those values will drive how long you will water? Also, how many days between watering are you seeing, and in what weather conditions?


#3

You may want to consider upgrading to rotators (such as Hunter’s MP Rotators https://www.hunterindustries.com/product-line/MP%20Rotator). They should provide better efficiency, a slower application rate to increase absorption, and you may get a rebate from your utility company.

If I replace my old sprinklers, my utility company is offering $4 per rotator head and $5 per sprinkler body with a check valve. Including the rebate for upgrading to the Rachio controller and adding a wireless rain/freeze sensor, my total rebate will be just under $500. My total upgrade (replacing 38 total spray bodies and heads) after the rebate should cost under $200. Well worth it even if I didn’t get the rebate from the utility company!


#4

I had a similar issue last year and addressed it with new MP Rotator heads. Here’s the thread in case it helps.


#5

@comsciguy and @azdavidr, what’s your payback period on your rotators? I thought about switching out my spray heads, but they are covering only 400 square feet so I’m guessing I’d save maybe 20-25K gallons per year if I could increase efficiency to 80%. In my case I think it would take quite a few years to pay for the rotators, but YMMV of course. My rotors might be a different story.


#6

I have not installed them yet, and will do it over the long 4th of July weekend. The current spray heads don’t have any pressure regulation and produce over three times the output of the new rotators. Plus, I still have dry spots and am probably over watering to cover those areas (I’m starting to see mushrooms popping up). I too have a small yard (around 1500 total sq ft), but expect to save approximately 2/3 of the watering cost since the new heads published output is 1/3’rd of the spray heads.

I’ll have to compare my water bill to see what the total saving will be, but after the utility company rebate the total upgrade cost including the new controller is around $200. I’m sure I’ll recoupe that this season.


#7

I didn’t do the math @ldslaron, but I do recall spending somewhere around $125 for my 500 sq. ft lawn. I hated seeing water running down the street for no good reason, and the overspray would spray my clean car when I backed out of the garage. My lawn wasn’t getting watered evenly either, so not only was I wasting water and spraying my car but my lawn didn’t even look good. All that seems to be taken care of now, so the anal-retentive engineer in me is not irritated by my sprinkler system anymore. Priceless. :wink:


#8

I may make this upgrade this year since the grass drives my water bill the most. Can the Hunter MP Rotators SR just easily screw onto my current rainbird popups?


#9

The MP rotators have a body and then the nozzles of various capabilities (throw distance, adjustment angles, etc.) are screwed into the bodies. I doubt that you would be able to use the Rainbirds, but maybe they have something equivalent? My new bodies are wider than the old, cheapo heads that I had in. I had to dig out enough area around the old heads to get my hand around them and screw them out, then put the new ones in. Not a big deal at all.

I love 2 things about the rotators. First, they are MUCH easier to control than my own heads with regards to precise angles and throws, so I get far less overspray and can dial in the coverage better than my old heads. Second, the lower flow rate does a much better job of delivering the water to the lawn surface, rather than misting into the air.


#10

Front Yard:
Area: 1100
Available Water: 0.2
Crop Coefficient: 0.7
Root Depth: 6
Allowed Depletion: 50%
Efficiency: 46%

Front Side Yard:
Area: 375
AW: 0.2
CC: 0.7
RD: 6
AD: 50%
Eff: 50%

Looking at the calendar, it looks like about 11 days (Water June 27 and again July 8). Both zones basically get full sun all day long. I’m in Kansas City so we’re look at mid 80s-low 90s, maybe a bit higher


#11

@tpayne, your settings don’t seem unreasonable - I’m guessing that’s clay loam soil based on the AW? Watering every 11 days seems like a long time but I live in the Phoenix area and I’m not sure what’s typical in KC. What ET values are you seeing in the moisture graph details? Assuming you were watering with another controller before, how long were you watering and how many days between?

@azdavidr, the perfectionist in me can relate to what you are saying about the rotators. Since the original concern seemed to about the water bill I wondered what the financial trade offs would be for @tpayne. I’m also curious for my own yard too. I’m probably too lazy to go dig up a bunch of sprinklers, though.


#12

I’ve been using the Rachio since last year. For the front yard, for the last week ET’s have been between 0.16 in - 0.25 in for each day.


#13

+1 on this seeming like a long time stretch. If you truly have clay it makes sense that the watering is deep and infrequent, but it’s worth double checking. If there is a disconnect on the soil setting maybe it was more forgiving in the winter time than now. Did you get the soil tested, or look it up via the Web Soil Survey ?


#14

Hmmm. Based on those settings I would think Rachio would water when you’ve lost 0.2 * 6 * 0.5 = 0.6". With those kinds of ET values I’d expect watering every 3 days or so assuming no precipitation. Would be curious to see the Moisture Level details.

Anyway, I’m not sure anything is obviously wrong with your settings so I think you might consider the tradeoffs regarding what others have suggested about improving system efficiency if you’re interested.


#15

@azdavidr I looked it up via WSS and I do currently have it set as Clay Loam.

@ldslaron I’ve run two rounds of catch cup tests on the front yard zone so maybe that’s messing with the timing of waterings?


#16

Some folks say that when their homes were built tons of soil were brought in and layered on top of the native stuff. If so that could make the AW of 0.2 too high. Just a thought.

Seems likely. You should be able to tell from the moisture graph details.


#17

The Hunter MP and MP SR’s screw onto a standard 1/2" male NPT (they are a standard 1/2" female NPT), since most sprinkler bodies are 1/2" male NPT they should screw onto your rainbird sprinkler heads.

However, the MP’s need to be pressure regulated at 40 psi (or possibly 30 psi) to get optimum performance and a consistant throw distance. This is best accomplished by switching out your sprinkler bodies with pressure regulated sprinkler bodies (30 or 40 psi). Sprinkler bodies with a check value (either pre-installed or field-installed) will give additional water saving benefits for down-hill sprinklers. Rain bird does sell a similar product (both the pressure regulated bodies and rotator heads), but I’m a Hunter fan.

The MP Rotator heads can be adjusted down by 25%. So, the SR’s would have a throw distance of 8’ - 10’ at 40 psi, 6’ - 8’ at 30 psi, and 10’ -12’ if a non-pressure regulated sprinkler body was used and the static pressure was ~ 55 psi. Note: the SR’s have a higher precipate rate of ~0.8 in/hr vs. the MP standard precipate rate of ~0.4 in/hr, so they are not suggested to be used in the same zone as the MP rotators, but can be with an adjusted schedule time (according to the Hunter tech I called).

The Hunter website has lots of videos and spec tables to help you determine just what you need.


#18

Not sure if this was answered or not @Modawg2k, but the MP Rotators will fit on pretty much and sprinkler body other than Toro. As long as the pop-up piston is a male thread, you are good to go!


#19

@tmcgahey Thanks, I just got a confirmation back from Hunter also that they will work. I may pull the trigger, but I gotta figure out this pressure issue that @comsciguy graciously provided. I know I won’t be digging up sprinkler bodies, maybe just one to check out what’s down there.


#20

I was able to use one of these recommended by @JPedrego. Based on where the tap was to the irrigation valves relative to my hose bib, I knew that the pressure at my heads was good based on the hose bib reading.

Start here, and read a few posts down.