How much water do we need

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We have been enjoying your magazine and gathering experience to buy our homestead. We've found a lovely place but the well only pumps 3.5 gpm. Can we run a garden,small orchard, chickens and maybe a horse with this much water. It's the first place we've found in our price range that actually has a liveable house and some flat land(11acres about half flat) We would appreciate some gentle advice

-- scott pepito (valleynook@juno.com), January 22, 2000

Answers

Scott: My last place had 3gpm well with no electricty so I built a 20 foot water tower that gravity fed back to the house. A solar water pump works great on that system but is expensive. Kirk

-- kirk davis (kirkay@yahoo.com), January 22, 2000.

That's about 5,000 gallons a day. That's nearly two million gallons a year. It sure ought to be enough to get you started - or better. Just make sure you've got adequate storage, and then that any overflow gets stored in a pond or dam. Make sure you plan for dam(s) to store your rainfall as well - preferably at least one uphill of what you might want to irrigate or otherwise run water to, so you can use gravity rather than power to deliver the water. Do some arithmetic on what volume of water falls on your house roof, and any sheds close enogh to maybe be useful as well. It ought to be way more than enough for CAREFUL household use for a year if you can store it. If not, at least try to divert it to the overflow storage for your pump. I'm talking from the viewpoint of Australia - "the dryest inhabited continent on the Earth" - wells mostly aren't a possibility, and where I grew up the annual rainfall was about twenty three inches, and we did okay - hardly ever had to cart in water.

I'd be planning, if I had the luxury, on getting to where I was never dependent on any one source of water. You could sure make a big start with the well though. You could run a LOT of chickens on a minute's worth; a horse on ten minutes worth; a grown fruit tree in a drought would be doing real well on a minute's worth (particularly if you had to carry it in a bucket); figure your own house usage - say wastefully luxurious at thirty minute's worth per person per day; and you've got 1440 minutes in a day.

Emanating envy!

-- Don Armstrong (darmst@yahoo.com.au), January 22, 2000.


3.5 GPM is average but what is important is the storage, in the casing, if you have a 100' well in a 6" casing, that tables up to within 6' of the top of your pipe, in theory you have about 135 gallons of water avaible with 3.5 gal. of recovery which means with a 10 GPM pump you can run about 15 minutes before you run dry. I once had a 3-GPM well and i was careful, ran out once in 17 years, in the heat of summer while running a sprinkler trying to grow grass, it recovered quickly enough.I was able to run an automatic washer okay. It is a good idea to have automatic shut off switch on the pump that will shut it down when the pump stats to draw air.

-- Hendo (OR) (redgate@echoweg.net), January 22, 2000.

Scott, I would suggest that you use the method Hendo gave you for figuring how much water is actually in the well at any given time. A quarter horse will require 10-15 gallons water/day, depending on the temperature and exertion. I believe the standard figure for chickens is 5 gallons/100/day. That leaves the rest for you and the garden and orchard. It really all depends on where you are located. If you are in an area that is normally blessed with a generous amount of rainfall you will naturally use less irrigation water than if you live in an arid place. Water consumption will also depend on how your family budgets its water usage. You may find that you will have to run the laundry several hours before you bathe. You may find that you have to retrain your family not to leave the water running while shaving or brushing teeth or washing dishes, but I would guess that your water supply would probably be adequate.

-- A.C. Green (ratdogs10@yahoo.com), January 24, 2000.

Scott, first of all, if you haven't yet actually bought the place, make sure that you either test the well, or pay a well testing company to test it. If the latter, BE there to observe how they do it.

There are a lot of properties sold with wells which don't produce but a small fraction of what they are alleged to produce. I could give you lots of examples, but won't.

If you do actually have a well which produces 3.5 gallons per minute, it may produce that much after an hour, or two, or four hours, then gradually produce less and less. Or not. All wells have different characteristics. I'm not trying to discourage you, but just to forewarn you.

My point is that you need to learn as much as you can about this particular well, about the type of formation the well is in, the history of well production in the area, etc. Talk to your Watermaster's offfice, if there is one, or the Department of Water Resources, or whoever has knowledge of the situation. Ask a well drilling company of pump company who to talk to, if you can't determine the correct office.

Most any well will gradually decliine if you continue to pump it, and many wells will produce less at the end of the "dry" season than they do at the end of the "wet" season. So the 3.5 gpm figure shouldn't be relied upon other than for the roughest estimate of how much the well will produce, assuming that it does, in fact, test out at 3.5 gpm.

I will give you ONE example. I used to live on a piece of land which had a 2 1/2 gpm well, as reported by the well driller. My neighbors' well was reputedly 10 or 15 gpm, I don't remember exactly.

Turns out that I was able to pump my 2 1/2 gpm well for several hours every day, without any noticeable drop in flow (I had no electricity, and had a windmill pump with a pump jack, which was actually powered by a 3 hp. gasoline engine. I had it set up to pump 2 1/2 gpm). My neighbors' well would only pump at 10-15 gpm for a few minutes, then would only produce about a pencil stream of water after that! (pencil stream = 1/4 to 1/2 gpm)

Now I have a 35 gpm well at my new place, but even here, I have recorded a drop in the static level. In the winter, it is a flowing artesian, but at the end of the dry season, the static level had dropped to 11 feet below ground surface. Now it's back up to 4' below ground surface, and will be flowing out the overflow in a week or so, if the normal rainfall continues. My new neighbor has two wells. One produces on the order of 12 gpm, and the second one, about 100 ft from the first, and 10o feet from my well, produces over 200 gpm. He pumps 35 gpm for ten or twelve hours per day from the latter well for irrigation, and uses the first well for domestic only. When my well had dropped to 11 feet, Dick's two wells had dropped to almost 50 feet. In fact, he sucked air out of his domestic well while irrigating from his strong well. We started monitoring our wells' water levels at that point, and he also cut back on his watering by about fifty percent. As luck would have it, his two wells are hydraulically interconnected, but my well is not connected with either of his. We are both very happy about this, as it prevents a lot of potential conflict.

I guess the point of all my rambling is to convince you that there is a lot to learn about your well, or any other well you might consider buying

Also, regardless of the availability of water where you end up living, I'd highly recommend diverting all your greywater except your toilets and kitchen sink out of your septic system. This will not only extend your septic systems expected life expectancy, but will help preserve your aquifer's health. This may or may not be a legal option for you, but many of us don't always do what's "legal", if we do what's "right", "safe", "healthy", and "environmentally sound".

-- jumpoff joe (jumpoff@echoweb.net), January 24, 2000.



I live in N. Nevada--average precipitation 7" and that usually from December through April. Our well hits water at 175' deep and pumps 2.5 gpm for about 30 minutes at a time with a recharge interval of about 1 hour. We have, at present, 1 dozen chickens, a duck, dog and cat, but have in the past had 3 horses, or a goat & a pig. I have approximately 40 fruit trees, three kinds of berry patches, 3 grapevines, asparagus, 250 feet of three foot wide garden beds, about 1/2 acre around the house landscaped, and a lawn 6' X 10'--all irrigated. I use lots of soaker hoses, group plantings according to water use, a lot of sand between planting areas, and water the trees on a slow trickle of water for 2 - 3 hours, once a week in the hottest part of the year. My husband scrounged a couple of water tanks, and we fill them with a restrictor on the tap during the night and then gravity-feed water everything from those tanks so as not to run the well dry. It can be done if you work at it. Good luck.

-- Jean Bondiett (j_bondiett@hotmail.com), January 25, 2000.

Jean, am I understanding you correctly? You are pumping 75 gallons in 30 minutes, then waiting an hour and pumping 75 gallons more? This equals 1200 gallons per day. If I understand you correctly, you deserve some sort of award for efficient use of water. Good Job! I'm very impressed.

-- jumpoff joe (jumpoff@echoweb.net), January 26, 2000.

hey scott! something i don't think you mentioned is the quality of the water. i don't know where you live or anything about the surrounding farms, operations, factories etc. i have a 160' deep well in s.e. illinois which i cant pump dry but---a massive hog confinement moved in about 5 years ago [i've been here almost 20 yrs.] and now we have hog manure in our water.-nitrates! answer? Black light and reverse osmosis system from sears at $450 uninstalled and filters,menbranes each year at almost $200. in addition to that lots of minerals have found their way into our well via oil wells and salt water injection wells on surrounding farms. i, too don't want to discourge you at all but please be aware of what could be a problem. i would encourge you to move rather quickly if it's what you're looking for. Time to move to the country is getting shorter and shorter as prices continue to rise. Good Luck and God Bless.

-- hoot gibson (hoot@wworld.com), January 26, 2000.

I know a guy who runs an organic CSA on 20 acres with, I think, 2.4 GPM. He has a 25 cow mother herd, many chickens 4 hogs, a sizeable greenhouse, and much land in vegetables and hay. His annual rainfall is about 25 inches. He captures the rainfall from his building roofs, as well, and does very nicely. I say, "Go for it!"

-- Laura Jensen (lrjensen@nwlink.com), January 27, 2000.

My husband said people with shallow wells might now understand how deep wells work. Hendo explained it with his letter, but I'll try to explain our system. The water table is at 157' (I transposed numbers above--sorry) and our 10 gpm pump sits at 212' It takes about 7 minutes to fill our 50 gallon holding tank, and then the well needs about an hour to recharge that 50' of casing. Any oftener than that and I run the risk of burning the pump up, and we certainly don't want to pull the pump unless absolutely necessary. So my average continuous usage is 1 gpm. That means I can't take a shower at the same time I do laundry. However, with a 1 gpm restrictor on the outside tap overnight, in the summer we fill the two 50 gallon tanks (and we've picked up one more to hook into the system next year) outside for the garden and orchard needs the next day.

-- Jean (j_bondiett@hotmail.com), February 03, 2000.


Jean, for cheap insurance against pump burnout, investigate replacing your pressure switch with one which has a low pressure cut-out. If the pressure falls below a certain pressure (typically around 18 pounds, in my experience, there is a little toggle switch which turns off the power to the pump. It has to be reset manually. There are lots of different, sophisticated automatic systems to help you recover a bit more water with less risk to your pump, but this one only costs ten or twenty bucks.

-- jumpoff joe (jumpoff@echoweb.net), February 03, 2000.

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