View Full Version : Irrigation from a pond
adegiulio
05-07-2007, 01:17 PM
We have a decent sized garden/orchard area that I would like to irrigate. Right now I am pulling hoses from the house about 150 feet. The pressure is unimpressive and often my well runs low (when I need to irrigate is when we have had the least rain, of course). I have a couple of ponds on the property that I would like to use as an irrigation source. Though I haven't measured, I would say they are about 20 feet below the garden, and about 200 feet away.
I'm thinking of a gas powered water pump connected to PVC or steel pipe running water to two tall sprinklers. Can anyone offer advice as to where to buy this stuff, what to buy, how to rig it up, etc. Any websites that are useful would be appreciated.
Thanks in advance!
speedbump
05-07-2007, 02:38 PM
I sell gasoline powered pumps made by Pacer. They are lightweight and economical to buy (not to operate). At $3.00 a gallon, you might be better suited to an electric pump. Copper is high too, but it's a one time investment and you won't be lugging gas cans back and forth. I recommend an electric jet pump. A 1/2hp will run two normal sprinklers with no problem.
Jet Pumps (http://www.pumpsandtanks.com/jet_pumps.htm)
Speedbump, why a jet pump instead of a submersible pump? I have a similar situation and was thinking of a submersible. Is one better than the other?
Bob
adegiulio
05-08-2007, 10:51 AM
I would rather go with a gasoline pump. It's just more versatile and portable, not to mention I don't want to string 300 feet of cable out there.
Anyone have some hints on piping?
speedbump
05-08-2007, 12:28 PM
"Speedbump, why a jet pump instead of a submersible pump? I have a similar situation and was thinking of a submersible. Is one better than the other?"
I prefer the submersible too, but the jet and gas pump are both centrifugals of sorts. I just thought he wanted it more portable.
Adegiulio,
What do you mean by any hints on piping? What piping?
bob...
adegiulio
05-08-2007, 02:50 PM
In my post I mentioned that the garden is about 20 feet above and 200 feet away from the nearest pond. I would need something to connect the pump to the sprinkler. What is the best way to do that? Tubing? Pipe?
speedbump
05-08-2007, 03:00 PM
The easiest would be poly pipe. It comes in a roll, wouldn't need couplings and would be easier to install. The size would depend on what volume of water you need.
bob...
adegiulio
05-08-2007, 05:04 PM
I dont even know...its about 1/3 of an acre all told. I figure based on the shape of things that I would need 4 sprinkler heads with a 30 foot watering radius. Most of the pumps I have seen online have a minimum 2" output. I assume it would be easy enough to step that down to an inch or inch and a half. Do I need to run that line into a manifold to split off to the four sprinklers, or can I just run them in series?
speedbump
05-08-2007, 05:09 PM
You could bush down to 1-1/4" if you like just to run four sprinklers. One inch would work also, but you might as well plan for future use. I wouldn't shrink the size of the suction, but the output is ok. Most normal (average) sprinklers that go 30 foot like at least 40 psi and will put out roughly 2.5 gpm. The smallest gas pump I have would do about 35 psi at that volume.
bob...
I have a Honda WX 10 water pump that I use for irrigation. It will suction lift up to 26' and I routinely run a couple of hundred feet of garden hose to the sprinklers. The only down side to this system is that it will only run one hour on a tank of fuel but after that hour it is time to move the sprinklers anyway. Attached is a link to the WX 10 but I don't know if it is still available as they now have the WX 15.
This works fine for me, but it will only run two sprinklers at a time, you might need more volume for your usage. pump (http://www.hondapowerequipment.com/ModelDetail.asp?ModelName=WX10)
adegiulio
05-17-2007, 03:54 PM
Thanks for the input. Do you use the pump to pull water from a pond also? Does the strainer that comes with the pump do a good job of keeping trash from the pump (and ultimately the sprinkler heads)?
Yes, we pull water from our pond. The strainer keeps large debris and fish out of the pump, but we hang the suction hose off of the pier to keep it out of the mud. Most of the debris in a pond is floating or on the bottom. So if you suspend your suction hose you are good to go, drive a tee post if you don't have a pier to hang the hose on. I have never had a sprinkler head plug up!
adegiulio
05-17-2007, 04:19 PM
Super...now all I have to do is find one on ebay... /forums/images/icons/smile.gif
speedbump
05-17-2007, 05:39 PM
"I have a Honda WX 10 water pump that I use for irrigation. It will suction lift up to 26' and I routinely run a couple of hundred feet of garden hose to the sprinklers."
The reason it will only run two sprinklers is the couple hundred feet of garden hose. That pump is rated at around 40 gpm.
bob...
adegiulio
05-17-2007, 05:46 PM
I'm not trying to be a wiseguy here, but why does the length of hose matter? If water isn't compressible, once it fills the hose, shouldn't the pressure be the same no matter where it's measured?
The hose constricts the flow, it is not pressure (well sort of) it is volume. It will handle more sprinklers if you increase the size of the hose but you are talking more expense. The garden hose and two sprinklers works fine for me and is easy to move around. I am no expert, just relaying my experience. speedbump will have far greater knowledge about pumps than me.
speedbump
05-17-2007, 06:08 PM
Not only does the hose restrict the flow, but it caused a great pressure drop as well. Garden hose is not always smooth inside so that adds even more. The bigger the pipe the less the friction drop in pressure.
bob...
adegiulio
05-17-2007, 06:43 PM
Ah, that all makes sense...I assume if I go with somelike like poly pipe, which is smoother and more rigid, that I can expect less pressure loss...
speedbump
05-17-2007, 06:48 PM
That's right and size is very important also. If you want to see how much, go to my website and look at the "helpful info" link. There are a bunch of charts there including the friction loss chart. The one there is for plastic pipe. To change the head in feet per 100' of pipe to pressure, multiply head in feet X 0.433.
bob...
adegiulio, Pumps are sometimes rated for the max pressure they can produce and the max volume they will flow. These are mutually exclusive. You will only get the high pressure with low or no flow and you will only get the max flow with no output restriction at all (low pressure.)
Better specs are those that tell you how many gal/min at a specified head of pressure, feet of lift, or equivalent.
The longer the run and the smaller the ID of the run the more losses you have. If you have to go long then you need to go bigger. The tables that Speedbump pointed out are indispensable for determining what actual performance to expect.
In math terms the pressure P and the volume V multiplied together is a measure of the work done. A given pump can only do so much work. The product of multiplying the pressure times the volume will be approximately constant. Doubling the volume of the flow in gal per min will cut the pressure in half and so forth.
Pat