I just installed a new well point well. My output is not very good. I have a 3/4hp pump with a 7 gallon pressure tank. I used a 1 1/4 inch galvanized pipe with a check valve and a 3 foot stainless steel sandpoint. I have a 40/60 pressure switch and I have the tank pressure set 2 lbs below the kick in pressure of 40. (that's according to instructions with the tank) We live on top of a aquifer and a few years ago ranch style houses had water in their basement. That would put the water table at about 7 feet. So I drove the sandpoint down to 17 feet and stopped and checked the water level in the pipe. I had 8 feet of water in the pipe which would put that 5 feet above the top of the sandpoint. So I stopped going deeper and hooked up the pump. It primed and the pump shut off at 60 lbs like it should. With a hand nozzle hooked up to my outlet faucet the water flow was bad. The pressure would drop down to 10 lbs and then back up to 20 lbs.
So the next day I disconnected every thing above the check valve and made a adapter to screw onto the galvanized pipe with a garden hose adapter.
I back flushed the pipe with 60 lbs of pressure from the cities water supply hoping that would clean the sand point screen. Hooked everything back up and this time I was able to run one sprinkler for about 2 hours with the pressure holding at about 40 lbs. After that length of time the sprinkler started slowing down and the pressure went down to zero and up to 20 lbs.
So the next day I got my son-in-laws big compressor and made another adapter so I could hook up the air tank. I thought by forcing the water back through the sand point I would clean it out better. After an hour I hooked up the water adapter and back flushed again for about an hour and a half. Hooked everything back up and was able to run a sprinkler for quite a while with a 75 foot hose. But then again the pressure dropped so I quit.
My conclusion is two things. I'm not replenishing my well fast enough to keep up with even one sprinkler. So I'm either not deep enough or I hit the bottom and maybe went into the bottom of the aquifer and maybe the sandpoint is in the clay and only part of the sandpoint is letting water in. If one foot is in the clay I only have 2 feet of screen letting water in to replenish my well, is that a big problem?
So, do I pull the pipe up or drive it down deeper?
So the next day I disconnected every thing above the check valve and made a adapter to screw onto the galvanized pipe with a garden hose adapter.
I back flushed the pipe with 60 lbs of pressure from the cities water supply hoping that would clean the sand point screen. Hooked everything back up and this time I was able to run one sprinkler for about 2 hours with the pressure holding at about 40 lbs. After that length of time the sprinkler started slowing down and the pressure went down to zero and up to 20 lbs.
So the next day I got my son-in-laws big compressor and made another adapter so I could hook up the air tank. I thought by forcing the water back through the sand point I would clean it out better. After an hour I hooked up the water adapter and back flushed again for about an hour and a half. Hooked everything back up and was able to run a sprinkler for quite a while with a 75 foot hose. But then again the pressure dropped so I quit.
My conclusion is two things. I'm not replenishing my well fast enough to keep up with even one sprinkler. So I'm either not deep enough or I hit the bottom and maybe went into the bottom of the aquifer and maybe the sandpoint is in the clay and only part of the sandpoint is letting water in. If one foot is in the clay I only have 2 feet of screen letting water in to replenish my well, is that a big problem?
So, do I pull the pipe up or drive it down deeper?