For the past two years I had been thinking about building a shallow well so I could water my grass without having to pay a higher water bill. After finding a 15% off coupon in the Harbor Freight ad I decided to get started. It took around 15 hours of work to complete and cost around $200 for the project. It would have cost less than $200 if I knew in advance which pipe and fittings I would be using. I had quite a bit of waste. I found very little info on the web on how to build a shallow well so I vowed to take some pictures and post the details on my Miata website. I hope this helps a few people.
I wanted to put the well close to my back deck where I could use the outdoor electrical socket for my power:
I would "hide" it in between the deck and the AC unit. Perhaps I'll build a wall or something to eventually hide everything:
Here is the pump I used. It is a 1 HP shallow well pump (Harbor Freight #47906). The pump is $139.99 (pretty inexpensive as far as pumps go) in the store but I had them price match it to the $69.99 on their website and then used my 15% off coupon:
I used water pressure to dig through the earth. Here is a rig I used to supply water to my 3" pipe. I later added a Y-fitting (the normal type you find in Wal-mart to connect two hoses to the spigot on your house) and a second hose for more water flow:
I cut teeth in the bottom of my 3" pipe to help dig through the ground. I used my 3 year old $15 Harbor Freight 4" angle grinder to do this. It gave it's life for the project though. When it quit half way through the project I switched to my pneumatic cutoff wheel.
I couldn't figure out an easy way to turn the pipe while I was drilling into the ground. Most of the time I used two bar clamps as handles. They had a hard time gripping the wet pvc pipe and caused a lot of headaches. The orange fence post level was a good idea but I got so tired digging that I rarely looked at it:
Every few feet I would run into hard clay. Here are some chunks that I pulled out. Yes, they look like rock and are just as hard. I had to break them up by raising up the pipe and slamming it down on the clay layers. These clay layers were so hard that the teeth would grind the teeth on the bottom of my pipe smooth. I'm writing this 4 days later and my body still hasn't recovered from the 8 hours of hard labor it took to dig down the first 18'. Note the water pruned hands:
After going down 19' with the 3" pipe (I'll call this a sleeve and use it to keep above ground water from contaminating my well) I could not get any lower. There was another hard clay layer and after trying for an hour I just could not break through it. I sawed some larger teeth in a 2" pipe, put that inside the 3" sleeve, and went to work on the 19' clay layer again:
It is hard to believe this pipe drops into a hole I dug with water:
After another hour of drilling, breaking teeth, cutting new teeth in the pipe and starting over I finally broke through the final hard clay layer. Around 21' down the water and dirt stopped washing up and out of the hole and all the water started being absorbed by the ground. This was the "water bearing sand" layer that I had been looking for:
Once the 2" pipe hit the water bearing sand it would no longer move down because the sand was absorbing the water and not allowing it to wash out. I used 3/4" pipe inside the 2" pipe to help move my 2" pipe further into the ground. By holding the 3/4" pipe with two water hoses connected to it just slightly lower than the 2" pipe it would blast away just enough of the sand to help the 2" pipe sink a bit. After going through about 3' of the sand I hit hard clay again and pulled my 3/4" pipe up:
After around 12 hours of digging I was just about finished. I had a 3" sleeve 18' into the ground. Inside that I had a 2" pipe 24' into the ground sitting on a clay later with 3' of water bearing sand above it. I glued my 4' long wellpoint (nothing more than PVC with hundreds of slots cut into it to act as a screen) to 20' of 1-1/4" pipe and dropped it into the 2" hole. I pressed down on it a little, trying to sink the point into the clay so it wouldn't move around any. I hooked water to the top of this and started back washing it. I was getting a very small amount of water coming back up and out of the 2" pipe so I was worried that my water flow from the well would not be that great. I started having second thoughts at this point that I would not be able to water the yard with this well. If the sand couldn't absorb my backwash water how could it supply enough water. After backwashing for a few minutes I pulled the 2" pipe up (leaving the 1-1/4" pipe in the hole) and allowed the sand to fall in around the wellpoint.
It turns out my fears were unfounded. After hooking up my checkvalve (you can see it just above the 3" sleeve), filling the pump and pipes with water, and turning everything on I had more than enough water. With one hose hooked up I get about 10 GPM out of this setup and 12 GPM with two hooked up. The pump has a tank with a bladder and a pressure switch. When only running one sprinkler, the pump will run for about 25 seconds (building to 45 psi) and then shut off for 25 seconds (dropping to 20 psi). Since you should not let your pump turn on and off like that I will make sure to always be running more than one sprinkler at a time. When running two sprinklers the pump only builds to 40 psi so it runs continuously. I have not tested anything past that but I'll have some fun playing with it in the weeks to come. I plan on adding some details to this page when construction of my in-ground sprinkler system is built:
My well installation was loosely based on these instructions I found on the Brady site.