Harvesting H2o (4 page)

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Authors: Nicholas Hyde

Tags: #Sustainable Living, #House & Home

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There is a difference between
well water
and
groundwater
. Well water is what you get from a professionally-drilled well. These are deep; typically 200–500 feet. Such deep-source water is usually safe to drink right from the well. Unfortunately, you cannot drill this type of well yourself and will need to hire the pros to come out with a commercial drilling rig. Be prepared to spend at least $4,000 for a proper well in most areas.

Groundwater, however, is most likely accessible a mere 10-30 feet under your homestead. You just need to go down there and get it. A groundwater well is also referred to as a
shallow well
. The water they produce is not generally considered potable. For that reason, most people who dig shallow wells do so for irrigation and cleaning purposes. That being said, knowing what you already know, this is a renewable source of reasonably clear water which can then be purified by one of the methods discussed in the previous chapters.

In third-world countries, water from shallow wells is commonly consumed straight from the ground, as it has been for thousands of years in all different cultures. It wasn’t until deep-well drilling techniques became possible from the industrial revolution in the 20
century that shallow groundwater was considered unsafe. Don’t ask me why. In ancient times, very large wells were dug, big enough to fit a team of diggers down the hole. If you go to Israel, you can see a Biblical relic at the city of Beersheba, which is supposed to be the well that Abraham dug in the book of Genesis. It is 12-feet wide and 50 feet deep, and was dug through a layer of limestone. Your backyard project will be much easier.

You should, of course, send a water sample from any well in for testing before consuming it. There is a pretty good chance the test from your own shallow well will come back as safe to drink, but do get it tested. Even if it does test as safe, I still advise purifying the water before drinking it. A home-dug well can become contaminated much easier than a deep well, so habitually purifying the water and having it retested often is highly advised.

Many people mistakenly think of groundwater as an underwater river or lake. That is only true in the case of springs. For the most part, groundwater is just a marshy earth layer which is located between other layers of earth. When you get down to the wet stuff, you will find coarser soil the deeper you go in that layer, until you are at a level of coarse sand. That is where the water can most easily be extracted, so that is the target for our shallow well. To get there, we need to first find the
water table
, go through marshy mud, and then a fine layer of sand (sometimes referred to as
water-bearing sand
). Beyond the fine sand, we get to the coarse sand where we end our drilling. If we go too far beyond that, we may hit another level of hard ground.

The hard ground that you must go through before arriving at the wet layer varies in texture regionally. In Michigan, you may have nice, easy, soft, muddy ground that you can slice through like a cake. In Missouri, you will probably find hard clay that you must slowly grind your way through. Down along the gulf coast, the ground is mostly sand, which sounds easy, but can present its own challenges (like frequent cave-ins). You should get an idea of the ground type in your area before you decide which home-drilling technique to try first. The best way to get this information is from other homesteaders in the area who have drilled their own shallow wells. You can also ask local professional drilling companies or specialty hardware stores who sell drilling equipment.

The other piece of information you need before you start is the local water table level. This is the layer in the ground where you first hit wet soil. The top area of this level will not provide good water, as it will be very muddy and marshy – but it will still have a primarily liquid consistency. The water table location is not an exact known place and can only really be determined by drilling, but it’s good to know whether your neighbors found water at 9 feet or 22 feet to give you an idea of what to expect. One website which may help is the United States Geological Survey site at USGS.gov. Search for the term “water table” followed by your county. You also may be able to get this information from local drilling businesses or rural family-owned hardware stores.

Drilling your own shallow well can be done quite inexpensively, although there is a good deal of manual labor involved in the process. There are several popular techniques you can employ, but they all involve boring a deep, small-diameter hole in the ground by the use of hand tools. The possible hazards include getting your drill pipe stuck, hitting rocks that are too big to be broken up, and your hole caving in. The only one of these problems which is unsolvable is the case of hitting hard rock. Usually rocks can be busted up and removed from the bore hole. One effective method for breaking rocks is dropping a heavy metal object into the hole tied to a rope, over and over. If you hit bedrock, however, you are done and will need to start over in a new location. (Bedrock is the hardest layer of earth and is not negotiable. Fortunately, the odds are slim that you will encounter it before you strike water.)

Most of the time when people think they hit hard rock they really just hit hard clay. Hard clay can be bored through by hand, even with plastic PVC pipe. You just have to keep working it. Don’t give up every time the going gets slow! I can almost guarantee there will be some slow patches, and the slowest one should be just before you hit the water table.

Whichever method you use for boring the hole, the goal is the same: To insert a
well screen
at the bottom of the hole in the coarse sand level, which will be attached to your well-casing pipe. A well screen is simply a coarse filter, usually made from either a wire mesh or simply thin slots cut in the bottom of the sealed pipe. This screen keeps large particles in the ground out of your drawn water. The well screen is typically at least several feet in length, and the top of it must be submerged far enough below the water table to be safe from ever coming above it – because if it does, the well screen will suck air and stop the pump from working. You may also wish to surround your well screen with a packing of small gravel, which will improve your well’s performance and provide an additional layer of filtering.

Another term you should be familiar with is the
well point
, which is simply a well screen with a point on the end, useful for penetrating at least some degree of ground (or gravel) when planting it.

It is more important to understand the concept behind well drilling than to follow a step-by-step set of instructions. That way, you can call an audible if need be and may be able to save your partially-drilled well with a bit of ingenuity when you run into problems. Many backyard well drillers started off using one method and ended up switching to a different one in order to finish the job.

Choosing a good spot for the well is important. It must be located at least 100 feet away from all sewage/septic lines (including garbage dumps or trash storage areas) and at least 50 feet away from any animal pens. It should be on an upward slope from your septic tank, if possible. Hopefully your land is not too hilly, as groundwater wells work best in flatter areas. Don’t be afraid of drilling under a tree, especially a large one. Large trees indicate that a decent water source is close by, and roots are easy to bore through. Having your water pump located in the shade can also be a plus. Just be cognizant of the need to occasionally have long pipes over your head while working, and remove any tree branches beforehand which figure to become obstacles during the process.

The problem of cave-ins can be avoided by keeping the boring pipe in the ground until a smaller diameter well casing pipe is in place; or, by using drilling fluid in the hole. Drilling fluid is usually made with
Bentonite
, which can be purchased via the brand names
Aquagel
or
Quick-gel
. Bentonite actually forms hard clay when mixed sufficiently with water, but for making drilling fluid less of it is used (just enough to thicken water). This thickened water is put down into the boring hole where it keeps the hole from caving in on itself. When the well is complete, the drilling fluid is flushed out.

The ground type and estimated water table level will affect the diameter of the hole you need to bore, which in turn will affect the drilling method you should choose. This is because a regular hand pump which works on suction, such as a pitcher pump, can only draw water from a maximum depth of 25 feet. This is an atmospheric pressure issue and cannot be changed. Therefore, if the water table is deeper than 25 feet, you will need to use a submersible pump (or another solution such as a jet stream pump) and those require a greater diameter well casing to fit down inside of. Please note that the depth of your well doesn’t matter so much as the water table level, since your well casing pipe will naturally fill to whatever level the water table is at. If you figure on needing to use a submersible pump, plan on having a well casing pipe of at least 4 inches in diameter. Most home-drilled wells find water closer than 25 feet and have a well casing pipe no bigger than 2 inches in diameter, hooked to a regular hand pump.

After the well is drilled to the desired depth, it’s time to flush the muddy water and drilling fluid out of the hole. This can be done with a simple suction-siphon technique, by thrusting a long pipe up and down continually at the bottom of the hole until water starts flushing out the top of the pipe over your head. Usually the pipe has an angled end-cap pointed away from the person doing the thrusting, so as not to soak them. If this doesn’t work the first time, fill the flushing pipe with water after it is submerged and that will start the siphon process for you.

Once the flushing is producing clear water, the well casing pipe with the attached well screen can be planted. The hole then needs to be filled and sealed in order to prevent contamination from above. Fill the hole around the well casing pipe with sand until you are reasonably sure you are above the water table. Then fill the rest of it with either cement or Benzonite (a thicker solution than the drilling fluid which will harden into clay). Fill the well casing pipe with water to in order to prime the pump, attach your hand pump, and pump until you have clear well water coming out. Voila, you have a well. If your pump does not include a one way valve, known as a
check valve
, insert one at the top of your pipe, but first install a T-section which will allow you to prime the pump below the check valve and then seal the T section off. This is all to prevent surface water from contaminating the well.

Auger Drilling

The simplest method of digging a well is simply digging it out using an extendable auger, the size used for post-holes (usually a 6” auger). This will only get you so far, however, and they become increasingly difficult to use the deeper you get. After about ten feet you will be lucky if you are strong enough to still turn it. I have seen videos of complete wells bored out using only an auger, but they were very shallow with water tables located no more than 10-12 feet. Normally, the well must be finished by using another drilling method. For all practical purposes, I would figure on using a post auger to dig a starter hole of no more than 7-8 feet and then continue from there with a different method.

If you are able to hit water at about 10 feet or so with the auger, that is shallow enough to probably be able to avoid cave-ins and you might be able to just finish the well with the auger. You need to get down below the water table by at least a few feet though, and the digging will now be slower because you will have at least some mudslide caving at the bottom of the hole. I would suggest putting the auger away at this point and inserting about 15 feet of 6-inch PVC pipe. This can be also function as your well pipe casing, if you wish. Once the PVC pipe hits bottom, begin flushing the mud out by thrusting a long thin pipe as described above. As you flush, you will be able to keep pushing the PVC pipe lower. When it gets to the ground, you will know you are five feet below the water table and can use that as a bucket-style well, or you can add another 5-foot section to the PVC pipe and go even deeper.

I would probably add another five-foot section at that point and try for another couple of feet of depth at least. As a much better alternative to a bucket-style well, a smaller-diameter PVC pipe with a well point fitted to the end can be inserted down the pipe all the way to the bottom, and then pea gravel filled in between the outer and inner pipes for a few feet. I would then probably remove the outer pipe casing and add a bit more gravel, then a large layer of sand, and then top up with cement. Finish the well by priming the pipe and attaching a hand pump. This should be a very productive well, going 7-8 feet below the water table and having a surrounding gravel pack at the well screen – especially if you use a large diameter well casing pipe such as 2-3 inches.

Driving a Well Point

A very popular method of backyard well drilling is not drilling at all, but swinging a sledge hammer to drive a well point to water. This method is a bit dicey, but probably worth a shot if you live in a flat area with reasonably soft ground and expect to find water at 20 feet or less. The type of well point used in this method is known as a
sand point
; a strong, metal piece containing a wire mesh well screen. It is fitted unto a narrow metal pipe, usually no bigger than 2 inches in diameter, which means you must use a suction-pump and therefore need to have a water table closer than 25 feet. A driven sand point will break up most small rocks it encounters without damaging the piece, but if you hit hard red clay your drilling attempt is probably done (and in all probability, you must sacrifice the sand point and the pipe in the ground).

If you expect to go down less than 20 feet, use 1.25” pipe; use 2” diameter pipe if you expect to go further. Metal piping is used in this method, usually in 5 foot lengths. Do not hit the pipe with the hammer! A small piece of equipment known as a
drive cap
is fitted over the end and that is what you strike. When the pipe gets down to the ground, remove the drive cap, screw on another 5’ length of pipe, put the dive cap on that end, and continue swinging. You will need something to stand on when starting off on a new length of pipe, such as the tailgate of a pickup truck.

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