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ricecake
02-01-2007, 08:05 AM
I have just recently picked up a few homes in a subdivision. The contractor told me that he want irrigation and Landscape installs on both. The subdivision is set up as a homeowners association. Therefore, they will have one 2 inch line attaching to each homesite supplying the irrigation water. What is the best way to get the correct flow and pressure readings from this line? There is another LCO in this subdivision doing irrigation, and I though about asking the contractor to call them and ask.

Flow Control
02-01-2007, 08:22 AM
I have just recently picked up a few homes in a subdivision. The contractor told me that he want irrigation and Landscape installs on both. The subdivision is set up as a homeowners association. Therefore, they will have one 2 inch line attaching to each homesite supplying the irrigation water. What is the best way to get the correct flow and pressure readings from this line? There is another LCO in this subdivision doing irrigation, and I though about asking the contractor to call them and ask.

Is the system looped? How many homes will be built total? Bring your supplier or local rep out. If the builder is offering X amount of guaranteed business, your local Hunter/Rain Bird rep would be slacking if he did not offer you some incentives to install a complete Hunter or Rain Bird system. Other things can also be negotiated with reps regarding model homes. Not really going to post anything here since it is a public site.


I would definitely talk to the other LCO, introduce yourself and feel them out. You guys probably have a lot more in common then you think. If they come off the wrong way then just say thanks for your time and have a nice day.

PurpHaze
02-01-2007, 09:22 AM
I have just recently picked up a few homes in a subdivision.

How big are the lots? How much and what type (lawn, planter, etc.) of irrigation is going to be necessary for each site?

The contractor told me that he want irrigation and Landscape installs on both.

So he has more than one irrigation/landscape contractor working on the overall subdivision. I foresee potential problems.

The subdivision is set up as a homeowners association. Therefore, they will have one 2 inch line attaching to each homesite supplying the irrigation water.

Where does this 2" line come from? Does it come from a central supply? Is there one backflow for the entire subdivision or will one need to be set for each lot? What about controller(s)?

What is the best way to get the correct flow and pressure readings from this line? There is another LCO in this subdivision doing irrigation, and I though about asking the contractor to call them and ask.

It all depends on too many variables. If you're using a common source then that is the best place to get the total PSI/GPM. If a special main line (or domestic water) has been supplied for the irrigation then you'll have to treat each site separately. You WILL have to work with the other irrigation/landscape subcontractor to insure that all systems will work. There must be coordination or the subdivision may be in for future problems.

ricecake
02-01-2007, 09:23 AM
I appreciate your help. I think that speaking with the other LCO is definately the quickest way to get the readings. Presently I think the other LCO is using Toro, but they are the largest Landscaping and Maintenance outfit in my area. I think that I will be using Hunter heads and Rainbird Valves.

PurpHaze
02-01-2007, 09:37 AM
Good luck. Seems that you guys will need some coordination between you to make sure things run right.

Flow Control
02-01-2007, 09:49 AM
Good Luck too, remember don't design at current pressure readings if it is a new and larger development.

ricecake
02-01-2007, 10:34 AM
How much should I plan on losing, I think that eventually there will be about 15 homes in a 7-8 acre area?

Flow Control
02-01-2007, 10:38 AM
Should not be a problem. I was not sure if it was a large scale development. Good luck, is there a slow time in NC for installs.

londonrain
02-01-2007, 02:22 PM
You need to find out the meter size and go from there IE: 1" meter w/60gpm, 2" meter w/ 120 GPM , etc. They do this type of system in my area and they use about 15pgm for each zone. The problem will be when each homeowner tries to run their system at the same time all the others are. I would size my zones on the lowend 10-12gpm and I would also use Rain Bird PRS spray heads.

PurpHaze
02-02-2007, 12:14 AM
How much should I plan on losing, I think that eventually there will be about 15 homes in a 7-8 acre area?

20-25% down the line in the future. Course, some guys don't care about the future. :)

Dirty Water
02-02-2007, 12:17 AM
I'm under the impression that there is a dedicated irrigation main. There may be a dedicated irrigation timer as well, and they are just expecting one zone per lot. I've seen it before and I hate it.

If thats what your looking at, consider MProtators for the heads.

Repairs
02-02-2007, 12:26 AM
I think I too would go with mp's as they perform well under lower pressure, and lower flow. I would also zone the sections 10% smaller than the neighbors flow wise. That way your customers will always have slightly higher flow than theirs if there is a problem, almost certainly assuring him that the other neighbors would raise heck about a soulution before he would need to.

ricecake
02-02-2007, 08:31 AM
I put a pressure gauge on the home, although, it will not be the point of supply. The pressure was good, about 85 PSI, however, the flow was only about 10 GPM's, explain that one. Maybe my gauge was malfunctioning. Business is slower, but if a man is good at lining his work up, he can install irrigation down here all year long. Blow outs are also a great way to rack some cash flow up.

Flow Control
02-02-2007, 08:48 AM
What was your source for measuring the GPM's?

Repairs
02-02-2007, 10:14 AM
Well if you did that flow test off of a 1/2" hose bib, that 2" out front ought to be really flowing, wheras if you took it @ a tee off the 2" line (which is the only correct way to do a flow test) then you have got your challenges.

sildoc
02-02-2007, 12:41 PM
The problem will be when each homeowner tries to run their system at the same time all the others are.

I have 2 areas with over 50 homes each where they designed a homeowners asso. with irrgation. each has individual timers and all want to water at the same time. you can tell in mid summer when it starts to get hot who all hasn't adjusted their watering schedule from the rest of the houses buy seeing major brown spots from lack of over lap.

PurpHaze
02-02-2007, 06:45 PM
I have 2 areas with over 50 homes each where they designed a homeowners asso. with irrgation. each has individual timers and all want to water at the same time. you can tell in mid summer when it starts to get hot who all hasn't adjusted their watering schedule from the rest of the houses buy seeing major brown spots from lack of over lap.

They just won't learn, will they??? There's only so much GPM/PSI to go around from one water source. I've had several sites where the district wants to add irrigation but the original pumps are maxed out with existing systems. Without coming up with another source of water it just won't work out right and it'll drag down the existing systems.

drmiller100
02-06-2007, 12:59 AM
the pressurized irrigation systems are getting more popular.
real world says you design your system correctly, and it will work just fine. then in a year you get a phone call from your customer of no pressure. EVERYONE sets their clocks to middle of the night or early morning, and once they build a few more houses, with everyone setting to same start times, pressure will drop at popular times.

Set your's to mid morning. (10 am). water is free, and you will have plenty of pressure when everyone else is not irrigating.