DIY Sand Point Well Tips
There are tons of videos on YouTube on driving Well/Sand points etc. This isn't a howto but more of a few ideas suggestions and guidelines.
A well point is essentially a perforated pipe with filter medium/screen of some sort that is driven/placed down into the water table allowing water to be drawn to surface. There's lot's of info on making your own from PVC pipe or commercially available Stainless Steel units. 1 1/4" is frequently used for 20' or less depths. And 2" for anything deeper than 20'. A shallow well pump can be used 25' or less and deeper requires a Jet Pump.
Checking Depths and soil conditions.
Before deciding on a Sand Point you may want to check with neighbors on well depths and soil conditions. Driving through clay or rock is extremely difficult and may damage the point causing problems. You may check with the US Geological service as they have a website that shows well info of monitored wells in your area. That can also give an idea of depth to water.
First of all one should use a mineral spirits soaked rag and run through your pipes to clean the oil and manufacturing residue out. Then wipe down outside.
How to install Sand/Well Point
If you have everything figured out then there are some different ways you can drive your sand point. Water jetting is a possibility where you drive a pvc pipe by pumping water through it and continually pushing it down. That hopefully wouldn't cause the hole to collapse before you put your sand point in the hole that is left. It also requires a water source to draw from.
There is also the auger method where you use an auger to make a deep hole and keep adding pipe sections till it's deep enough. Again hopefully the hole doesn't fill before you get your sand point in there.
Or you can just drive(hammer) the sand point in. Use a post hole digger or auger to get a hole started 3-4' then begin driving your point with maybe a 10' pipe to start since it's gonna be down a bit. Then use 5' sections or again a 10' if you know it's gonna be down a ways. Use Drive Couplings since normal pipe couplings can't handle the impact and will break. On the top, use a sacrificial nipple before the Drive Cap. That way if you mess anything up it will be the nipple and not the actual pipe threads of expensive pipes.
Or there's the good old fashioned drive method. Be sure to use a designated drive cap. Use a hammer drill with appropriate attachments/customizations, fence post driver or sledge hammer. If you have access to a mini escavator/backhoe you may be able to push or drive it down with that. Let me tell you, it's easier than swinging a sledge hammer :) Essentially whatever method you can use to drive it in will probably work.
Reaching water
Once you get down a ways you will probably see a reflection of water or dropping a large bolt or wrench on a string will allow you to measure the depth and static water level. Drop to bottom then pull up and see how much water you end up with. There's tons of info out on how you shouldn't drink water from a shallow well etc. You will have to decide that for yourself.
A well point is essentially a perforated pipe with filter medium/screen of some sort that is driven/placed down into the water table allowing water to be drawn to surface. There's lot's of info on making your own from PVC pipe or commercially available Stainless Steel units. 1 1/4" is frequently used for 20' or less depths. And 2" for anything deeper than 20'. A shallow well pump can be used 25' or less and deeper requires a Jet Pump.
Checking Depths and soil conditions.
Before deciding on a Sand Point you may want to check with neighbors on well depths and soil conditions. Driving through clay or rock is extremely difficult and may damage the point causing problems. You may check with the US Geological service as they have a website that shows well info of monitored wells in your area. That can also give an idea of depth to water.
First of all one should use a mineral spirits soaked rag and run through your pipes to clean the oil and manufacturing residue out. Then wipe down outside.How to install Sand/Well Point
If you have everything figured out then there are some different ways you can drive your sand point. Water jetting is a possibility where you drive a pvc pipe by pumping water through it and continually pushing it down. That hopefully wouldn't cause the hole to collapse before you put your sand point in the hole that is left. It also requires a water source to draw from.
There is also the auger method where you use an auger to make a deep hole and keep adding pipe sections till it's deep enough. Again hopefully the hole doesn't fill before you get your sand point in there.
Or you can just drive(hammer) the sand point in. Use a post hole digger or auger to get a hole started 3-4' then begin driving your point with maybe a 10' pipe to start since it's gonna be down a bit. Then use 5' sections or again a 10' if you know it's gonna be down a ways. Use Drive Couplings since normal pipe couplings can't handle the impact and will break. On the top, use a sacrificial nipple before the Drive Cap. That way if you mess anything up it will be the nipple and not the actual pipe threads of expensive pipes.
Or there's the good old fashioned drive method. Be sure to use a designated drive cap. Use a hammer drill with appropriate attachments/customizations, fence post driver or sledge hammer. If you have access to a mini escavator/backhoe you may be able to push or drive it down with that. Let me tell you, it's easier than swinging a sledge hammer :) Essentially whatever method you can use to drive it in will probably work.
Reaching water
Once you get down a ways you will probably see a reflection of water or dropping a large bolt or wrench on a string will allow you to measure the depth and static water level. Drop to bottom then pull up and see how much water you end up with. There's tons of info out on how you shouldn't drink water from a shallow well etc. You will have to decide that for yourself.
Piping
For fail safe leak free joints, wrap teflon tape 4-6 layers and a thin layer of pipe dope will virtually always seal well and prevent leaks.
I suggest driving a 2" sand point,
that gives you the option to drop a 1 1/4 pvc drop pipe from the pump
with a check(foot) valve. Makes easy pipe checks and valve
replacement. The 2" pipe comes up from ground to a 2” threaded
Tee with a capped off/plugged side for access/test/shock, then from
top of Tee is a short 2” nipple with a 2” PVC cap with hole
drilled large enough for a male and female threaded 1 1/4" pvc
threaded through it and sealed with plumbers putty. So the drop pipe
goes up and glued male pipe fitting goes through 2” cap hole then
female threaded fitting screws on tight to secure 1 1/4” through
the 2” cap and suspends it. Then from the 1 1/4” female threaded
fitting up is a short piece of pvc into a Tee. The pump inlet runs
off to side to pump and from the top of that Tee is a short pipe and
a male threaded fitting with a Cap to seal it off. That gives quick
easy access to fill/prime drop pipe and pump, or could be used for a
hand pump addition, or easy access for shocking the drop pipe
checking water etc.
The advantage you have with driving a
2” with a 1 ¼ drop pipe is if there is a leak in threads of 2”
and it won't hold it's prime it's irrelevant. But it would be a
problem with just a 1 1/4”. With the 2” driven, it's a casing for
the 1 1/4” and leaks won't matter. As long as the pvc drop pipe is
sealed. It helps to sand down the outer diameter of 1 1/4” couplers
or threaded fittings so they slide into 2” easier with less chance
of getting stuck. It shouldn't but it's easy to do. Some recommend not using couplers or fittings because they are weaker and just using pvc with the bell ends and gluing solid. If it's shallow I don't know if it really matters. A bit deeper and more pipe, yea maybe an issue.
With a foot valve virtually the whole drop pipe stays filled with water so minimal priming is needed if inlet is opened for pump repairs etc. It's also a good idea to keep drop pipe off the bottom of sand point just in case sand enters the point.
With a foot valve virtually the whole drop pipe stays filled with water so minimal priming is needed if inlet is opened for pump repairs etc. It's also a good idea to keep drop pipe off the bottom of sand point just in case sand enters the point.
I described my idea to a plumber who
had worked on sand points before. He said that would have saved him a
couple days of labor and unhappy customer on a job where they had
driven a replacement 1 1/4” sand point in a basement and could
never get the water drawn up. They tried everything and eventually
gave up and walked away saying sorry to the customer and no pay for
the job. Possibly there was a leak/damaged coupler that leaked and
prevented pump priming/suction.
Or one can just use the 2" with a reducer to 1 1/4" then into the pump.
Or one can just use the 2" with a reducer to 1 1/4" then into the pump.
You will need to use a pressure tank pressurized correctly for your pump switch pressures. The larger realistically the better since your pump will cycle less. The stop and starting of your pump is hard on it. So a larger tank will allow the pump to just run for a few minutes at a time.
This is one view of a setup under construction
When you are pumping good clean water after all that work...it's a wonderful feeling
Water Testing
One should shock the well after running it clear for a few hours if it will be potable. Then testing the water is an excellent idea. Most home or hardware stores will have a test kit. It also wouldn't hurt to send a water sample to a lab to actually test it and see what kind of chemicals are in there. With the amount of chemicals used in agriculture today it's very possible there's contamination.
Water filters are a good idea and are commonly available all over. Many times you will want at least a 2 stage filtration. The first to catch the majority of the contaminants and the second a charcoal for taste. Otherwise use the water as is and use a drinking water filtration system or reverse osmosis for drinking.
Things to avoid
I contacted a pump manufacturer service dept and they said PVC unions shouldn't be used on the inlet side of pump. They have had frequent problems with leaks etc One MAY be able to use a galvanized union without problems. But hose connections are generally pretty easy.
This is a vid of what it sounds like when there's a leak in the inlet.
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