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The washdown method looks interesting, but not sure what I'd do when I want to penetrate the shale. Also, I do not have running water at my lot.
The steel bar down the center of the casing and driving the well point directly seems like a great idea. However, I still don't trust the crappy Chinese well point that I bought to try this with.
When my father and I did his well, we hauled barrels of water up from a creek a half mile away. We also captured the waste water and reused it after we let the clay settle out of it. At the bottom of the clay layer, we ran into a hard layer that the locals called hardpan that was tough to bust through but once we were through it, the well took all the wash water so we knew we broke through into the aquifer.Originally Posted by ETD66SS
I decided to try and salvage the well screen from the Northern Tool well point, and use it in my existing 17' deep well to try to filter out the sand.
Existing well is 17' deep 4" PVC casing, and a pitcher pump with a foot valve 14' deep.
http://www.infinity-universe.com/~de...n/DCP_1107.jpg
http://www.infinity-universe.com/~de...n/DCP_1111.jpg
I cut off the bad threads on the well screen, and installed a plug on the bottom end, and adapters on the end that I coupled to the PVC drop pipe.
http://www.infinity-universe.com/~de...n/DCP_1108.jpg
http://www.infinity-universe.com/~de...n/DCP_1109.jpg
http://www.infinity-universe.com/~de...n/DCP_1110.jpg
I measured the static water level, to my surprise it was 6.5 ft below grade, it had gone up a lot since the last time I fiddled with the well. Which is odd, because we have not had any rain.
When I placed the screen down into the casing, I hit sand in the bottom of the well casing, it seems to be about 3 ft of fine sand in the bottom of the well. I massaged the screen into this sand all the way down. So the well is at full 17' deep, and the screen is about 30" long. So roughly, from the top of the screen to the static water level, there is about 8' of water "height"
I primed the pitcher pump and started pumping, I pumped it dry rather quickly, and I waited and waited, and the well never recharged in the 30 minutes I was playing with it.
I took a washer on a string and droped it in the casing. There is no water in the well at all...
As stated before, I got 3 GPM with the foot valve, albeit sandy water. Now I get nothing...
Does this mean even if I got the drive point to work, I would have had the same issue?
Is my sand just too fine to allow any kind of flow?
If there is no water in the casing, then whether or not the sand point is too fine or not is moot. Water in the casing would be before it goes through the sandpoint.
Then why can I get 3 GPM with the small footvalve, and I get nothing with the sandpoint?
I guess I don't understand why the casing replenishes with the footvalve, and not the sandpoint. I didn't expect that to happen...
I'm a little late getting into this but as the pond level goes down so will the flow from any shallow well near it. In most areas you're just circulating the water from the pond back to the pond. The only way to obtain 25 gpm from a well in your area is to have a deep well with a submergible pump. Sorry what is, is!
Porky Cutter, MGWC
(Master Ground Water Consultant)
If there is an impervious layer of clay between the pond and the aquifer the well is drawing from, it is possible that the two are not one aquifer. That said, 7.5 feet probably is not enough to be impervious and the pond could well be part of the same aquifer.First 7.5 ft is sandy loam.
Next 2.0 ft is red silt clay.
Next 5.5 ft is blue-gray silt loam clay.
At 15 ft, glacial till...
Even if they are not the same aquifer, when the pond level goes down so too might the well level so the small margin of 8 feet probably would not go far.
Well, I don’t believe this to be the case in my situation, as I accounted for this when I dug my ponds. The local water conservation specialist from the DEC informed me that the water table in the spring is 18” below grade, and at the driest time of year it is usually at ~68” below grade.In most areas you're just circulating the water from the pond back to the pond.
When digging my pond, I clay lined the sandy loam portion of the banks, to prevent my ponds from dropping drastically as the water table fell.
This picture shows the anatomy of my pond banks: http://www.infinity-universe.com/~de...nk-Profile.jpg
If what you said were true, my ponds would be at the same level as the water table, but they are not. The water table atm is about 6.5 ft from grade, the pond water level is at 3.5 ft from grade.
I lose water for many reasons:
-Evaporation
-Wicking into the banks and evaporating (pond banks are always wet, so I know this to be true)
-Water leeching through the gray silty clay lining into the sandy loam. (This gray clay is not like capping
clay, water can still pas through it slowly)
Now, I know even if I pump water into the ponds, I will still lose it due to all the above reasons, but I believe if I can attain 25 GPM, I will be able to keep the ponds near the springtime water level all year round. If not, it will still be better than letting it drop 2.5-3 ft from May until Sept. As that is about how long it takes in a very dry year like this. The ponds drop about 36” in 120 days. 25 GPM for my pond area gives me the capability to replenish 1” per day of pond level.
The local DEC office tells me shale rock is after the glacial till, between 18-20 ft deep. That is where the water veins start.
This is why I believe 2-3 shallow wells into the shale rock will work for me. Most wells in my neighborhood seem to be between 25-35 ft casings certainly not the 100’s of ft you guys seem to be implying.
This is one thing I have not found good information on. Why do you say a deep well with submersible is required for 25 GPM. Why is it that multiple shallow wells combined can not get me to 25 GPM?The only way to obtain 25 gpm from a well in your area is to have a deep well with a submergible pump. Sorry what is, is!
Last edited by ETD66SS; 07-16-2012 at 09:00 AM.
Well, after all that BS with the crappy Chinese made sand point junk, I had a well dug last Oct. They went down 46 feet with a 19 ft long 6 in casing and got real nice water, he was afraid to go any further because in that area if you go any deeper you hit salt. At this moment in time, the water level in the casing is only 3 ft from grade.
The rig operator told me he got 4 GPM (even though the guy on the phone who quoted me the job said the closest well in that area got 12 GPM, so I could expect to get around at least 10 GPM, then when the rig operator finished the well I asked him why I'm only getting 4 GPM, he said "for this area you're lucky to get 2-3 GPM" gee, thanks for the scam.
I assume if it says 4 GPM on my well cap, I should buy a well pump that is 3 GPM or less?
This is not sufficient for my pond filling needs anyways, so in the end it was a waste of $$.
Also, the well driller told me water from that depth is not from the same aquifer as the water table and the ponds, so I would definitely not just be circulating the water. (but he does sell drilled wells for a living and that company already pulled a fast one on me...)
Last edited by ETD66SS; 03-16-2013 at 05:12 AM.
Can you explain the formation better? How does one have only 19 feet of casing in a 46 foot hole? What is the remaining 27 feet, uncased clay, rock, screen, ???
Maybe the well can be developed to get more GPM.
He hit the bedrock at 18 ft, went into that 1 ft with the casing, the rest of the depth is just rock. That is how it is done in my area he said.
I live very close to Lake Ontario. I guess after you get through the bedrock, you hit salt deposits. ~45' is as far as they will go in that area. He told me most area wells they only go down ~30 ft, but he had to go down to 46' to get any water at all. At first he was getting 0 GPM, then he shocked it a few times, and ended up with 4 GPM.
How can I test the GPM of this well on my own?
It was drilled during one of the worst droughts on record, I don't know hos good his 4 GPM number really is for a normal season...
Last edited by ETD66SS; 03-16-2013 at 07:33 AM.
You drop in a submersible and tape an air line to the drop pipe. Put a Tee on the top of the air line so that you can have a tire valve and pressure gauge on it. Pump air into it with a small compressor and the pressure you see will tell you how low that water level is. Simple math based on .43 PSI per foot.
Put a ballvalve on the water line to regulate the pump output and adjust it so that there is at least a foot of water above the bottom of the air line. Measure how much water you get in a minute and do the math.
Ok, makes sense. However, the reason I want to measure it is to know what kind of submersible to buy
I assume I can use some cheapo plastic car battery operated submersible to test with, something I know has more GPM than the well would have?
Pumps run on a curve. You choose the pump based on GPM and total head. Just don't buy more pump than you need. You can simulate more head simply by choking the output with a ballvalve.
http://www.wellpumpsandfilters.com/S...urves_b_1.html
Yep, I understand the curve.
But maybe I'm still confused.
My plan was to buy a cheap submersible, use your method for measuring the GPM. If I understood it correctly, I was going to put the pump with open air line in about 4 ft, hit it with a small compressor and the gauge would have a reading. Crack the ball valve and keep opening it until I see the pressure drop. Regulate the ball valve until I see the pressure holding steady. Then measure how much water I get in 1 minute.
However, I don't want to go buy a final submersible until after this test, as they are like $600. I was hoping to get a cheap (~$100) unit form Home Depot or something that can do at least 15 GPM. However, I'm not finding any that will fit in a 6 in casing.
I guess for my test I don't need a submersible, I could use a shallow well pump. Maybe something like this: http://www.northerntool.com/shop/too...9977_200349977
Last edited by ETD66SS; 03-16-2013 at 09:32 AM.
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