underground water lines, what size plumbing

   / underground water lines, what size plumbing #21  
There are tricks to irrigation. Like, most spray heads, only want a max of 25psi. If you go over 25pis, they mist instead of spray, and do not give you good coverage.

And, head to head coverage... If you turn on just one sprinkler head, it will actually be dry right next to the sprinkler head; spray or rotor. Head to head coverage takes more sprinkler, but the overall system will cover properly.

It's also important to keep spray heads with spray heads, rotors with rotors. And, keep the same brand and style on a circuit, so you have consistent matching precipitation rates.

If you are on a well, you want to make sure the well stays on. You do not want it to cycle. Either you have to have the correct number of sprinkler so it flows enough to keep the well going, or you have to add a relay to the well.

The links I provided above really help figure out gpm and psi on well systems.
 
   / underground water lines, what size plumbing #22  
I guess I will have to dig up all those sprinkler system I installed years ago and seem to be working, using 35 psi with the rotors at a 35 ft spacing.

Manifolds were 1 in and the rest 3/4 and 1/2 in pvc.
 
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   / underground water lines, what size plumbing
  • Thread Starter
#23  
all i want to do is add 3 hose bibs to my property at the dimensions shown to water trees at the edge of my property line with a 100' rubber hose that i will detach and reattach. At most i MIGHT use 2 100' rubber hoses attached to the hose bibs to water the grass with removable sprinklers.
 
   / underground water lines, what size plumbing #24  
when measuring GPM from your well. make sure the well pump kicks on, GPM when you first turn on the the water can be higher vs once the "well tank / pressure tank" has went down, and has caused the pump to turn on.

for length of pipe/hose run for your garden hose hooks ups, i would say 1" and use the black poly pipe (normally black, some times comes in different colors pending on were you live)

i would also either upgrade house plumbing inside, to 1" or tie into the pipe between well and house. before it gets reduce down to 1/2" thought i would lean to wye'ing / tee'ing into plumbing on the outside of the house. to reduce friction loss.

sch 80 plastic or some sort of metal threaded adaptors as other have said would be advised to use outside, and using some sort of metal pipe with garden hose faucet to change between the black poly pipe that is buried below ground to transition up and out of the ground to the garden faucet. for areas that deal with frost. having a good garden hose faucet, that extends deep enough into the ground is worth it. and helps protect against bursting pipes.

full port valves, goto a local hardware store, and look at various valves, in plumbing section, also look at some brass gas valves. you will notice some valves only have a little "pin hole" going through valve, while others when fully open there is no reduction inside of the valve. when you get into garden hose valves for outdoor faucets. there is a rod inside of the pipe that either extends back into the house side, or down into the ground. these rods do cause extra friction loss. but trade off is dealing with frost / freezing / cracking of pipes.

if you are needing to deal with cold winter freezes, it might be advised, to be able to come up with a way to drain the water going out to these water faucets, perhaps installing a full port valve down in the basement, before tee'ing / wye'ing off to the various branch circuits you are wanting to install.

for the barb fittings that will be below ground that will need pipe clamps. i might advise double up the pipe clamps, and then put a small coating of silicon over the screws on the pipe clamps. ran into some problems of pipe clamps stating stainless steal, but for what ever reason they were wanting to rust up pretty good. when i went back and had to fix a leak or redid things and saw how things looked.

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if you are going to install an actual sprinkler system, vs moving a garden hose and sprinkler around. i would most likely change a good amount of what i noted above.
 
   / underground water lines, what size plumbing #25  
Spray heads need 15-25psi generally. Otherwise, they will mist instead of spraying. My note about the psi was just for those pop-up spray heads.In this example, these Rainbird spray nozzles want 15-30 psi(at the sprinkler, not the valve).
Rain Bird U-Series Spray Nozzles

Rotors are another animal compared to spray heads; I have seen them run from 25-50psi or higher, depending on the make, model, nozzle, the supply line, and the desired spray distance/precipitation rate/GPM. These particular rotors want 25-65psi.
Rain Bird 5000 / 5000 Plus / 5000 Plus PRS Series Rotors

I guess I will have to dig up all those sprinkler system I installed years ago and seem to be working, using 35 psi with the rotors at a 35 ft spacing.

Manifolds were 1 in and the rest 3/4 and 1/2 in pvc.
 
   / underground water lines, what size plumbing #26  
if you are needing to deal with cold winter freezes, it might be advised, to be able to come up with a way to drain the water going out to these water faucets, perhaps installing a full port valve down in the basement, before tee'ing / wye'ing off to the various branch circuits you are wanting to install.
There is no way to get all the water out by trying to drain the sprinkler system in the basement. The most effective way to winterize a system is by using an air compressor attached to the manifold, and blowing the water up and out of the heads. Attach the compressor to the manifold, set the air pressure to about 60psi, and manually cycle through the zones, giving each zone about 2 minutes to clear. Using this method, you can get 98% of the water out of the system, and prevent any possibility of freeze damage to the piping.

Here are tons of links to learn from:
winterizing sprinkler system - Google Search

Here is a useful representative video:

for the barb fittings that will be below ground that will need pipe clamps. i might advise double up the pipe clamps, and then put a small coating of silicon over the screws on the pipe clamps. ran into some problems of pipe clamps stating stainless steal, but for what ever reason they were wanting to rust up pretty good. when i went back and had to fix a leak or redid things and saw how things looked.
A single quality hose clamp is enough. That said, the right way to to this is to use Oetiker clamps. They go on much faster, are far more reliable, can not strip out, will not corrode, and if you are doing more than a dozen connections the cost is lower even factoring in the upfront investment in the crimp tool.

Oeteker clamp - Google Search

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Wrooster
 
   / underground water lines, what size plumbing #27  
There is no way to get all the water out by trying to drain the sprinkler system in the basement. The most effective way to winterize a system is by using an air compressor attached to the manifold, and blowing the water up and out of the heads. Attach the compressor to the manifold, set the air pressure to about 60psi, and manually cycle through the zones, giving each zone about 2 minutes to clear. Using this method, you can get 98% of the water out of the system, and prevent any possibility of freeze damage to the piping.

Here are tons of links to learn from:
winterizing sprinkler system - Google Search

Here is a useful representative video:

A single quality hose clamp is enough. That said, the right way to to this is to use Oetiker clamps. They go on much faster, are far more reliable, can not strip out, will not corrode, and if you are doing more than a dozen connections the cost is lower even factoring in the upfront investment in the crimp tool.

Oeteker clamp - Google Search

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Wrooster

good note on air compressor. for most part have written off an air compressor, due to dealing with larger size pipes up to 4" in size on ponds. and not having enough velocity of air moving through the pipe to clear out the water when using air compressor, and need for a lower point to drain water to. 1" pipes should have enough inside cross section to allow air to slowly allow all the water to flow back out of the system. now 3/4" or smaller size pipe, i would be using air compressor to blow them lines out.

never needed to use a specialty tool, for clamps, the projects that have came up. there just not enough to invest in a tool and clamp setup. and then buy if need be a special tool to undo the clamp.

as far as double clamp or single pipe clamp for barb fitting. ya a single pipe clamp should be all that you need. though there are multi barb type patterns. personally tend to use the longer barbs that have any were from 4 to 6 little ridges. the hose gets pushed over. allowing for 2 clamps to be placed on. each clamp goes between 2 of the ridges.

another issue i have, half the time i end up finding myself in this little bitty cramped area on most of the projects. and the need to have a regular small size socket wrench, and regular nut driver screw drivers, and then couple size flat head screw drivers come in handy. were i just could not see how a specialty tool would allow me to get into those areas easily, ya i am sure i could figure out a way, but i would be done and moved on to next clamp and be done with it.

there are times i will use a 2 ridge or 2 ribbed barb fitting, but normally only time i use them, are on softer hose material, like a garden hose, or some of the cheaper non re-enforced hoses you pickup at local hardware stores. were the hose itself is almost a rubber that can be squished. vs a black poly pipe. that is a harder plastic. and normally need to use some sand paper or a small sanding drum from a dremal to make a little better inside edge of hose. to get the hose initially started on the barb.
 
   / underground water lines, what size plumbing #28  
He is only wanting to run some garden hose for water supply.

1 in hose may be hard to find

There is 3/4 hose out there, but if you look in the end of the hose, it may be only 5/8 in due to the fitting.

Put a gage on the end of the 100 ft hose and measure pressure, That will be static pressure.

Remove gage and turn on water to fill a 5 gal bucket. 1 min = 5 GPM, 30 sec = 10 GPM

Here are some figures/charts that may help.


GPM/GPH Flow based on PVC Pipe Size, ie, How much water can flow through Sch 40 Pvc Pipe Size 1/2" 3/4" 1" 1.5" 2" 2.5" 3" 4" 6"
 
   / underground water lines, what size plumbing
  • Thread Starter
#29  
ok so after talking with my well driller and checking my current pump output i do not think it will handle 1" line to where i need it and changing the pump is not in the budget. I thought this was gonna be a simple plumb some line and let the water go. But with all this information about letting the pump run on and off and having the pump run dry or the pump not being able to keep up with the demand.

So what can i do here to have some water out where i need it? should i just use my 1/2" line and let the pressure be what it is i know its not going to be significant but atleast water is where i need it.

any thoughts?
 
   / underground water lines, what size plumbing #30  
What do yo mean that your pump will not handle a 1 in pipe.

Your pump can fill and pressurize any size line.

The larger the pipe, the less resistance to flow.

Just how many GPM is your pump pumping?

I have used mostly 3/4 in PVC in the systems I have installed.

The output will be based on the pressure and the GPM that your pump can provide.

You match up the sprinkler heads for the pressure and flow.

The only way to increase flow and pressure is to get a larger pump.

As far as letting the pump run, while using a sprinkler, the idea behind that is you will have constant pressure and flow.

If you use the bladder tank. the pump will fill the bladder shut off and let you draw down a certain amount and then repeat the cycle.

The preferred way is to have the pump running continuously. A small tank, about a 1.5 gal tank is required on most sprinkler system or a timer and relay to keep the pump running.

You can also test your setup by laying out the line above ground and connect everything to a pump, and and test everything.

If it works to your satisfaction, then bury the line and be happy.

If you have a tractor, you can use the subsoiler to dig and pull the PVC line.
 

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