Well depth
#1
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Well depth
I know they say that you cant pump below 26' in a shallow well with 1 1/4" pipe, if you use 3/4" with a foot valve are you still limited to 26"?
Thanks
Thanks
#2
Welcome to the forums! You won't get enough volume from a 3/4" pipe for it to be viable. 26 or 33' is the maximum before the water begins to boil due to lift. What are you proposing to do? I would stick with the 1 1/4" pipe.
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I drove a well by hand, I’m down 60' with about 12' of water in 2” pipe. I used cheap drive pipe from Menards and the pipe bulged at the couplings and I cant get the packer jet past the bulges. I was just trying to see if I could salvage all the hard work.
#6
Here is an interesting thread that may help you since it uses 1" PVC instead of 1-1/4"
http://www.doityourself.com/forum/we...deep-well.html
http://www.doityourself.com/forum/we...deep-well.html
#7
I think you may find that the problem you have pertains more to the laws of physics than it does to the size of your pipe(s). As long as you have your pump up at the surface, you have to rely on the pump to create a vacuum strong enough to draw the water from your well's water depth . . . . but even if you have a pump powerful enough to suck the water, you'd have to create such a complete vacuum that the water would always choose vaporize than be lifted in its liquid form.
Depending on what your local elevation is, your atmospheric pressure is still in the neighborhood of 14.7 pounds per square inch (at sea level). No pump (no matter how strong it is, or how big its motor is) can lift water up by suction more than 33.9 feet. The reason for this is that a column of water 33.9 feet high, exerts a pressure of 14.7 pounds per square inch, or exactly 1 atmosphere of pressure. When a pump tries to suck water up a pipe from below, what is really happening is that the pump creates a vacuum at the top of the pipe, and atmospheric pressure forces the water up the pipe toward the pump inlet.
Since a column of water 33.9 feet high causes a pressure of exactly 1 atmosphere at the column's bottom, atmospheric pressure cannot push it up any higher, even if the pump could create a perfect vacuum above. You can boil water at room temperature if you drop the pressure low enough.
I only know this because 40 years ago, at a remote cabin I used to own, I tried endlessly to overcome these laws by attempting to suck water up 50' from a pond using a gasoline powered pump to fill a 100 gallon water reservoir in our ceiling (for gravity feed domestic uses). I wound up lugging to pump down to the source, and pumping the water uphill.
Good luck.
Depending on what your local elevation is, your atmospheric pressure is still in the neighborhood of 14.7 pounds per square inch (at sea level). No pump (no matter how strong it is, or how big its motor is) can lift water up by suction more than 33.9 feet. The reason for this is that a column of water 33.9 feet high, exerts a pressure of 14.7 pounds per square inch, or exactly 1 atmosphere of pressure. When a pump tries to suck water up a pipe from below, what is really happening is that the pump creates a vacuum at the top of the pipe, and atmospheric pressure forces the water up the pipe toward the pump inlet.
Since a column of water 33.9 feet high causes a pressure of exactly 1 atmosphere at the column's bottom, atmospheric pressure cannot push it up any higher, even if the pump could create a perfect vacuum above. You can boil water at room temperature if you drop the pressure low enough.
I only know this because 40 years ago, at a remote cabin I used to own, I tried endlessly to overcome these laws by attempting to suck water up 50' from a pond using a gasoline powered pump to fill a 100 gallon water reservoir in our ceiling (for gravity feed domestic uses). I wound up lugging to pump down to the source, and pumping the water uphill.
Good luck.
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For a surface pump, the depth of the well isn't as important as the "drawdown" depth.
The drawdown depth is the depth of the water when the pump is running and is hard to measure sometimes.
So for your example, you have a good well that is 60 feet deep, the static depth of the water is 12 feet and when you hook up the pump and start running it full blast, let's guess that the water level drops to 20 feet. This is not an unreasonable guess -- drawdown should not exceed 10 feet because if it does, that means it's not a "good" well meaning the screen is not in water bearing soil (usually coarse sand or gravel).
A well is good or bad based upon if it can produce the amount of water desired. An irrigation well often is asked to produce ~15-20 gallons per minute and if it can't, then it is "bad" for irrigation, but is "good" for a well used for drinking water because most houses only need 5 gallons per minute. There are people that live in places where water is hard to come by and they are happy if they can get 1/2 a gallon per minute and they are very happy because they had to go down hundreds of feet to get even that little bit.
Your well will work fine because if the drawdown doesn't exceed ~25 feet, which is where pulling water becomes difficult and it becomes impossible at 33 feet.
The only time you need a packer is if the drawdown depth exceeds 25 feet. From what I read (and that is all I know about them because I live in Florida where they are rarely used) packers are not a good idea. They get stuck and can't be easily removed. There are inflatable ones that might be easier to remove.
The pipe from the well should either exceed or match the input side of the pump. If your pump has a 1" input, then 1 or 1 1/4" pipe should be used. If the joints are good, then an elbow could be put right on the 2" pipe and then run input pipe (or hose designed for suction) to your well directly.
How much screen did you put at the bottom? You drove this with a sledgehammer?
The drawdown depth is the depth of the water when the pump is running and is hard to measure sometimes.
So for your example, you have a good well that is 60 feet deep, the static depth of the water is 12 feet and when you hook up the pump and start running it full blast, let's guess that the water level drops to 20 feet. This is not an unreasonable guess -- drawdown should not exceed 10 feet because if it does, that means it's not a "good" well meaning the screen is not in water bearing soil (usually coarse sand or gravel).
A well is good or bad based upon if it can produce the amount of water desired. An irrigation well often is asked to produce ~15-20 gallons per minute and if it can't, then it is "bad" for irrigation, but is "good" for a well used for drinking water because most houses only need 5 gallons per minute. There are people that live in places where water is hard to come by and they are happy if they can get 1/2 a gallon per minute and they are very happy because they had to go down hundreds of feet to get even that little bit.
Your well will work fine because if the drawdown doesn't exceed ~25 feet, which is where pulling water becomes difficult and it becomes impossible at 33 feet.
The only time you need a packer is if the drawdown depth exceeds 25 feet. From what I read (and that is all I know about them because I live in Florida where they are rarely used) packers are not a good idea. They get stuck and can't be easily removed. There are inflatable ones that might be easier to remove.
The pipe from the well should either exceed or match the input side of the pump. If your pump has a 1" input, then 1 or 1 1/4" pipe should be used. If the joints are good, then an elbow could be put right on the 2" pipe and then run input pipe (or hose designed for suction) to your well directly.
How much screen did you put at the bottom? You drove this with a sledgehammer?
Last edited by Vey; 07-14-14 at 07:14 AM.
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This sounds like what i was thinking and seems correct. I have 25 foot of pipe and the water after measuring multiple time is at 13 feet in pipe. My problem is my 1 1/2 HP pump. It isn't flowing good at all. When i ran pump which is new it sounds rough so i puled prime plug to take a look thinking i would get hit the face with it just is bubbling in there and pouring out of garden hose a little. I put spigot at discharge to water lawn. I posted a thread before i read yours so figured since my shallow well is just like a florida well type, one 1 1/2 inch pipe down to water and up to my pump. No well novice but it just seems to defy logic. Pump water out and water lawn...easy right! Well not so much.