Shallow Well

[tdriver]

I live in NW New Mexico about 1 mile from the San Juan river on five acres. The water table is very high. You can dig a two foot post hole in several areas and it will seep water into the bottom.

I would like to dig a shallow well for irrigation. What I had in mind was to dig about a 10' deep hole with a back hoe. Install a two or three foot diameter perforrated pipe. Back fill with 2" washed gravel and set up an insulated pump house. The questions I would like to ask are:

- Does this approach sound viable?
- What type and size pump is best for this application? The garden area is about 1500 sq ft. I would like to run a pipe across the property and also irrigate two acres of grass.
- Would it be prudent to include a pressure tank in the installation? I would like to set this up for the ability to hook up a hose and do small water along with large watering applications.
-
Thanks for your advice

[Mike Pastorelli]

Sure this sounds good and will work...
Here is what I would do with that high water table. ( I'm a cheapskate )
Dig down about 6 feet and use the 4 inch perforated pipe and create a big loop down there ( forego the gravel and use the fabric filter to keep sand out of the pipe ) Then pick yourself up a harbor freight 12 watt submersible pump with a head lift of 6 to 8 feet ( about $15 bucks ) 280 gallons per hour.. Purchase 100' of 1/4 inch vinyl tube or hose and get ahold of several 55 gallon plasti drums and fill them up.. You got water where you need it for dirt cheap electric consumption and at 12 watts you can pump constantly.. Those small pumps can run constantly without a problem for like 4 years straight... Move the hose around and water whereever.. This is one set up I have when the rainy season hits here in Florida and it works beautifully...

[valveman]

It all depends on the porosity of the soil. If it only “seeps” in to the well, you probably can’t do much with it. But if it pours into the well at 5 or 10 GPM, then you can do some irrigating. Small gravel is better than large gravel. The gravel just needs to be large enough not to go through the perforations in the casing. The smaller the perfs in the casing, the smaller the gravel you can use.

You might also be able to just hammer in a few drive points and tie them together. They have small enough screens that you don’t need gravel.

After you see how much the drive points or the dug well will make, then you can design a pump system for that much water. You will have to use a jet pump with the drive points, but you can use a submersible if you have 4” or larger casing in the dug well.

A pressure tank and pressure switch is the best way to control the pump if you plan on using hoses. A CSV would keep the pump from cycling to death and allow the use of a very small pressure tank. Or you can use as large a pressure tank(s) as you can afford or have room to install to reduce the cycling somewhat.