We've now been living on our property for a couple of months and just wish we had done this a long time ago. God blessed us with the sale of our old home in 3 weeks from listing to closing [img]/forums/images/icons/tongue.gif[/img] and we've actually got a little extra $$ out of the deal.
The subdivision house we just moved out of had an 8 zone lawn sprinkler system that was the one of the best things we ever did. I thought it was great and would like to do the same here on the new place, but there are substantial differences.
I am familiar with how to determine pressure and gpm requirements, zoning, layout, etc for a "typical" house setup, but we will have some much longer runs that I don't think can be handled by the 2hp well pump that we have. I have only started to look into this, so the only info that I currently have is that we run 55-70 psi pressure at the well, haven't checked anything else or run any real calcs yet.
A very preliminary look at layout gives me 7 zones, but 2 of them will each need to be about 700 ft to accommodate irrigation of young trees along a long driveway. The other zones vary in length from 200 to 500 ft each. Obviously only 1 zone will operate at a time.
I'm thinking that a booster pump will be needed to supply adequate volume/pressure, but since I will not have a pond to draw from, the well itself will need to be the source. What I'm trying to figure out is if I will need an additional holding tank that the booster pump would draw from - the well pump would fill the holding tank. Hope I described that OK.
Thanks in advance for any help/advice you've got. Also thanks for past info on setting up filters for the water supply to the house. I bought 2 filter assemblies from FarmTek (very reasonable cost) and installed them in parallel in the water supply line. Very good pressure in the house and absolutely no sediment issues at all.
Dear 283: Somewhere along the line, you'll have to discover how much VOLUME the sub can pump at sprinkler pressure over a long period of time. Take that number and derate it for dry years when the well pumping level is lower; then you can start dividing up the place into zones. If you have 50-70 psi, you probably won't need a booster unless you are on some steep slopes or you puke away all the pressure by undersizing the pipe and accumulating gobs of friction loss. Ideally, the sub should run continuously during watering; not be cycling on and off IF POSSIBLE, and some industrial-grade sprinkler timers DO HAVE a provision for over riding the pressure switch and keeping the unit pumping steady. Remember that if you run that sub at very low discharge pressure for prolonged periods of time, it will load up the motor and may trip out ....or burn up....so be careful about that. When I did this every day in California I used to figure about a horsepower per acre for watering in that dry, politically-correct, perversion-dominated, and otherwise whacked-out climate. [img]/forums/images/icons/crazy.gif[/img]
Thanks Dave. Next step was to do as you recommended to find what volume I was dealing with. Our place is flat so the main consideration there is the pipe sizing. For most of the longer runs, since I'm figuring on drip irrigation for specific tree and plants, not general area watering, hopefully the lower gpm or gph requirements should help.
Thanks for your help.
PS- the 283 was pulled when I first built the car in favor of a 454/th400/Ford 9 driveline [img]/forums/images/icons/grin.gif[/img]
i am also going through this right now...i just talked to my well guy who has dug several of my neighbors wells, and he told me with a shallow well (200-225 ft.), i shoud expect between 18-22 gallons per minute....i am trying to cover about 1 1/2 acres with bermuda grass. I had my sprinkler guys come out last week and they marked off and put the flags for the rotor heads at normal spacing (60 ft i believe) i would require about 105 rotor heads!....that would require 26 stations!....the well guy recommended a varible speed pump on the well for the long runds i would have to have (500'-600')
this was all going to require 1 1/4" line from the well to the valves and then drop to 1" pipe to the heads.
Great info - thanks. I have a manifold valve assembly at the well pressure tank outlet that reduces the 1 1/4" outlet pipe to four 1" ball valve outlets: house supply, shop supply, general watering (so I don't use filtered house supply), and sprinkler. I was re-thinking the 1" sprinkler supply sizing, so your post came at a good time. In my case, the rotor heads would be only for the immediate yard right by the house. The longer runs for trees along the driveway would be serviced by drip heads so the gpm requirement is reduced.
My current plan is to first get all the pipes sized correctly, then add a water reservoir (750-1000 gal) and booster pump for two purposes - one would be to add additional supply and pressure for any sprinker system, the other would be for a fire hose connection. I know this would not be a full blown hydrant setup, but at least better than a garden hose I would think.
Don't know if I'm nuts to consider this, but it doesn't seem unreasonable to want to combine the water usage. Comments are appreciated [img]/forums/images/icons/wink.gif[/img]
Once again, it's a matter of supply vs demand. Once you know the capacity of your well and pump at sprinkler pressure, you can do the planning. Having a squish tank and a booster pump is OK if you know what you are doing. Usually, the justification for that is that there is an area of the water system that requires higher-than-system pressure and by using a booster pump you can keep the head low on the rest of the demands and save that pumping head and the resultant horsepower. EXAMPLE.....a landscaper has some low pressure drippers and shrub heads on five of the six circuits. The sixth circuit has big rotators with a high pressure requirement. He sets it up so that the timer kicks in the booster pump start solenoid when set number six starts watering. The squish tank helps to reduce pump cycling if the well gets slightly ahead of demand. [img]/forums/images/icons/tongue.gif[/img]
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