School Me on Lawn Irrigation Systems

Ron

Ron

Dum Spiro Spero
Moderator
Joined
Apr 16, 2005
Location
Sharon, SC
Ok geniuses educate the idiot (me)

We bought our house 5 years ago. The builder went belly up mid construction. We inherited a nice chunk of equity for being able to see past a lot of small stuff. The biggest thing at the time was there was never a yard "installed", the house was built on a hill and there were massive run off ruts. You could lose small children in these things. We spent a small fortune building a level yard. Hired a "pro", trucked in 20 dump truck loads of "top soil" and another 50 of fill dirt. Harley raked, planted, straw matted, fertilized you name it.

I went with a 20% rye 80% fescue blend to stabilize the dirt quickly. We had a very warm fall and the rye exploded. The ground was still so puffed up you couldnt walk on it much less mow and soon the rye topped out. Nearly choked all the fescue out. Year 1 we had a 70% lawn.
Year 2 I aerovated, over seeded and fertilized in the fall. Pre emergent in the spring and had about a 85% lawn
Year 3 did it all again and had about a 85% yard again.

I got frustrated spending a couple grand a year to make grass to cut and it wasnt "right" so Ive ignored it the last 2 years. And about 50% of my yard looks like a better homes and garden magazine cover, 40% is green, mostly weeds and 10% has bare/thin spots.

I've soil sampled and such and know what I need to do chem wise this fall. But I am also coming to realize without proper irrigation Im never going to get there. Looking around the irrigation material is cheap. I own a trencher. So with a little time Im thinking I can handle this fairly cheaply.

Here are some beginning questions I have I am hoping the board can help with.

- How many sprinkler heads can an average city water supply support at a given time? The net seems to have conflicting info.
- Since I will exceed this number I am guessing I will need a multi zone controller or a manifold device and manually control it. Any input here?
- My biggest concern and the reason I honestly havent done this before now. My house is on a private septic tank. The tank is in front of the house and uses a pump to pump the crap up hill to the drain field which is in the front yard. Pretty easy to tell where the drain lines are, they are bright green all summer. I am unsure how deep they are and very concerned about hitting them with the trencher. I will have to cross the entire drain field to get all the way to the road. Assuming I screw up here, and I will, how hard is it to repair a septic drain field line?
- How deep do these irrigation lines need to be. Im thinking not only about minimizing hitting lower stuff, but also about freeze protection.

Any other experience do's and dont's?
 
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In for learning too because it has been dry as heck around here for the past few weeks or so and I've already had to bust out the sprinkler in mid April!
 
I got tired of having a 40% yard and installed a yard wetting system last summer. Other than the hard physical labor aspect of fighting the trencher around, laying out pipe, and recovering the trenches, it was pretty easy. Most of the sprinkler manufacturers have an interactive system planner on their websites. I used one, and it showed that I needed something like 25 different heads, a bunch of runs of pipe, and a few different zones. I scrubbed that information down to 6 big heads and 2 zones. That gave me about 95% coverage, and a few areas that overlapped a bit. After running it, I realized my well couldn't support 3 heads once the pressure tank ran out of pressure, so I split it from 2 zones into 3 zones, and now it works great. Got everything from Lowes/HD. Could have a saved a little by ordering online, but not enough to bother with it since I thought I might return stuff anyway. I have all of my valves and controller in the well house, so wiring was very simple. I probably could have saved a little bit on pipe by running a trunk line and putting controllers out in the yard, but I like the simplicity of everything electrical/mechanical in one place.
 
jeepinmatt said:
After running it, I realized my well couldn't support 3 heads once the pressure tank ran out of pressure, so I split it from 2 zones into 3 zones, and now it works great.
Click to expand...

That is exactly what I am worried about. I borrowed two BIG tripod style sprinklers from my FIL last fall when I completely redid my lawn. My well could only power one at a time or they both wouldn't spin properly. Was it major tear up to change it from 3 heads to 2 per zone? I'm starting at zero knowledge here but starting to convince myself this project is going to happen this year.
 
drkelly said:
That is exactly what I am worried about. I borrowed two BIG tripod style sprinklers from my FIL last fall when I completely redid my lawn. My well could only power one at a time or they both wouldn't spin properly. Was it major tear up to change it from 3 heads to 2 per zone? I'm starting at zero knowledge here but starting to convince myself this project is going to happen this year.
Click to expand...

If you know what your well capacity is, you can design the system into properly sized zones.

jeepinmatt said:
I scrubbed that information down to 6 big heads and 2 zones.
Click to expand...

How far apart are the heads?
 
All will depend on what GPH your system and intake from the city source can provide. You'll have to start with that number and go from there. More zones doesn't necessarily mean a substantial extra cost invested in most systems. It just means you'll only be able to run X amount of heads at a time but you should have the same number of heads to cover your area anyway. Wish I had more insight for you but the only systems I have experience with are all well based or direct source off a lake where we knew the GPH provided by the pressure tank or the HP/Flow rate of the intake pump and were able to design the system around that.
 
Thanks.
Thats where I am as well and not sure how to et that info other than, opening a valve wide open for a sample size period of time and extrapolating.
 
drkelly said:
That is exactly what I am worried about. I borrowed two BIG tripod style sprinklers from my FIL last fall when I completely redid my lawn. My well could only power one at a time or they both wouldn't spin properly. Was it major tear up to change it from 3 heads to 2 per zone? I'm starting at zero knowledge here but starting to convince myself this project is going to happen this year.
Click to expand...
I had to retrench about 100ft without tearing up the line I had already laid. Honestly using the same trench probably made it harder than just trenching new, but it was an afternoon's work. I used 3/4" pex with crimp connections, so tying in and adding/changing connections was easy.

shawn said:
How far apart are the heads?
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I think they are about 65ft, and the spray distance was around 35ft from the head. I'm pretty sure these are the ones I used:
Shop Orbit 4-in Plastic Gear Drive Sprinkler at Lowes.com
That "50ft" spray distance is a joke, and requires some crazy GPM, and is more of a stream than a water curtain.

I used a 35ft string and dropped different color flagging tape around the radius to see where everything would overlap and where it would miss. It was close enough.


Ron said:
Thanks.
Thats where I am as well and not sure how to et that info other than, opening a valve wide open for a sample size period of time and extrapolating.
Click to expand...
This is actually the best way, but make sure your sample size is sufficient. The well guy said my well would do 10gpm. My 5 minute test said it would do ~8 gpm, but I neglected to realize that the pressure was dropping over that time, and flow is related to pressure. Later testing confirmed the real number was about 5.5-6gpm. After it failed to maintain pressure, I pulled up the pressure and flow curves on my pump and found the numbers matched perfectly to my retesting, but that was hindsight. The heads I used were somewhere around 2.3-2.5gpm, so I can run 2 and the well will cycle and maintain pressure normally. In your case, the supply should be much more constant, because the "pressure tank" is the entire municipal supply system.
 
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jeepinmatt said:
In your case, the supply should be much more constant, because the "pressure tank" is the entire municipal supply system.
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Until he runs out of pipe capacity.
 
Don't forget that when you hook to a municipal supply you have to pay for a separate tap and install an RPZ backflow device that must be inspected annually by a certified tester. The tap fee where I work is $1800 and the RPZ will run about $500. The annual inspection will cost around $75.
 
Not where I live. We don't have those.
This will just T in right behind my main shutoff valve for the house anyway.

Municipal system is generous. Our system is 75 houses on 1 water tank fed from 3 large wells. No treatment or fluoride added just a big tank full of water...
 
Something to keep in mind...
I'm on a well, so I don't pay per gallon, but at 5gpm, running the various zones a total of 2hrs per night equals out to about 600 gallons per day consumption. That's watering about 5/8-3/4 acre, and I have no idea if I'm doing it right, but the grass seems to like it.
 
I pay .14 per 1,000 gallons.
It won't break me.
 
Ron how much area are you looking to irrigate?

Get me your gallons per minute, and pressure coming before any pressure reducers, and I will design you a irrigation system

I have done tons of designs and installs back in my younger days, used to be good money, I quit doing a bunch in 2009 when the housing market went to shit because guys were installing them for a little over cost

Example, class 200 pvc it rigation pipe in the 1" flavor will carry 11 gallons per minute, so with 1" zone lines which I prefer, you could run 5 heads with 2 gallon per minute nozzles and still support the flow, or example 9 heads on one zone with 1.5 gallon per minute nozzles,hunter pgp heads are nice, easy to adjust and will last a while in the ground
 
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guffey24 said:
Ron how much area are you looking to irrigate?

Get me your gallons per minute, and pressure coming before any pressure reducers, and I will design you a irrigation system
Click to expand...


Awesome.
How do determine the pressure?
 
Sounds like Guffey24 has this one. :rockon:I'm an old pro at irrigation too but y'all carry on. Please don't hesitate to ask if you need anything.
 
I'm not 100% sure there is even a Pressure Reducing valve on our house, tbh.

I can see the service entrance point clearly and it looks like a straight pipe feed.
 
R Q said:
Sounds like Guffey24 has this one. :rockon:I'm an old pro at irrigation too but y'all carry on. Please don't hesitate to ask if you need anything.
Click to expand...

I used to get most of my stuff through Simmons Irrigation down in Charlotte

That's were I was going to recommend him buying, maybe you can hook him up with some contractor pricing through somebody down that way?
 
Ron said:
I'm not 100% sure there is even a Pressure Reducing valve on our house, tbh.

I can see the service entrance point clearly and it looks like a straight pipe feed.
Click to expand...

Buy one of these and stick it on the hose bib and see what you get
image.png
 
Ron said:
I'm not 100% sure there is even a Pressure Reducing valve on our house, tbh.

I can see the service entrance point clearly and it looks like a straight pipe feed.
Click to expand...
It would be in a separate valve box just after the meter or at the entry point where the water line comes in the house.
 
guffey24 said:
I used to get most of my stuff through Simmons Irrigation down in Charlotte

That's were I was going to recommend him buying, maybe you can hook him up with some contractor pricing through somebody down that way?
Click to expand...
I use strictly Toro supplies but will gladly yet you use my contractor pricing at STI. They do have other products than Toro. If you/he works up a complete list of supplies we can run it by them for pricing. But don't use a Toro controller, Rainbird makes a much better one.
 
R Q said:
I use strictly Toro supplies but will gladly yet you use my contractor pricing at STI. They do have other products than Toro. If you/he works up a complete list of supplies we can run it by them for pricing. But don't use a Toro controller, Rainbird makes a much better one.
Click to expand...

Smith Turf & Irrigation, yeah no problem

Yeah I like the ESP's myself
 
@guffey24
@R Q

Bringing this back from the dead. Finally got the numbers above

~65 psi and ~10.5 gpm
 
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