QUESTION: Hi Jim,
I'm researching installing an irrigation system. I have a point well that's not in use as a source of water. I have 1 acre of grass to irrigate. I'm wondering what the most cost effective way would be to get water over the whole acre. I would think the easiest way is to have all valves in one big valve box near the point well, which is located right behind my garage, which has power. But if I do that, I'm guessing I'd need to run 1 inch pipe from every valve in there, which would probably be 10 or more, to each area. But it seems crazy to run a new 1 inch line out to each zone. Another thought is I run a 1 inch line to 3 or 4 areas, and then run zones off of those main lines. But then I have to get wire to all of those locations. What's the best way of doing this?
ANSWER: Hey Jay, there would be a lot of different factors to look at to properly design the system. The biggest thing, would be how many gallons per minute the well would be able to produce and at what pressure the pump puts out. Each head would use x gallons per minute, and certain heads could easily throw 40 feet if you have about 50PSI, but normally this type of head would use around 4 gallons per minute. Lets say you get 20+ gallons per minute from the well, If you are using a head that uses 4 gallons per minute, then you could run 5 heads per zone. Instead of putting all the valves in one location, I would run the mainline (the line that the valves are hooked to) down the center of the field you are trying to water. I would have a valve installed and run a set of heads perpendicular to the main line, and probably have one valve facing one direction, and another valve facing the opposite direction. Or if you can put enough heads on one line, have one valve in the middle of the field, that runs heads perpendicular to the mainline on both sides of the mainline. It is easier to run wire to the valves, then it is to run all that pipe from one location. Hopefully this will give you a little more direction, Good luck and have a great day.
---------- FOLLOW-UP ----------
QUESTION: That helps a great deal, thank you! It makes sense to run a main line. I can run one to my back yard, one to my front and one to my side yard. I know I use a pipe puller to run the irrigation line. what's the best way to run the wire so it gets beneath the surface?
I have to figure out what the well can do. I have no idea. All I know about it is it's 15 feet deep and there's water at about 12. Also, I was told by the prior owners that it once serviced what was farm land behind the house.
thank you again
Hey Jay, we normally use a 18 gauge multi strand wire. This wire can be bought with anywhere from 2 strands up to 15 strands. It is a direct burial wire, and the wire has a plastic jacket around the wires that are inside of it. Determine how many valves you have in one area, lets say 3 valves. You will need at least a 18/4 wire (18 gauge/ 4 strands). Each valve needs its own hot wire, and each valve will share a common wire. We normally will run an extra wire to each location, just in case a wire goes bad, or you need to add a valve. To a 3 valve manifold, we would run a 18/5 wire. You can pull your wire with the pipe puller, normally when you pull in the mainline, just attach the wire to the front of the pipe, and pull the pipe and the wire together. Good luck and have a great day.