Septic systems: On-site evaluations for water wells

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On-site evaluations for water wells are often taken for granted by builders. I have known many builders who have submitted bids for work without ever seeing the building lot. This practice can be risky. One of the risks relates to the water well, when one is required.

A builder can't bid a job competitively without knowing the type of well that's going to be used. If a bid goes in for a bored well when a drilled well is needed, the bidder loses money. If you try to compensate for not inspecting a site by basing your bid on the most expensive type of well, you stand a chance of unnecessarily bidding too high and losing the job. Failure to do a site inspection can be a very big mistake.

What can you really tell by walking a piece of land? It depends on your past experience and skill level. Some conditions point to obvious solutions. For example, when I built my last home, I was able to see bedrock sticking up in places. The type of humps in the land indicated rock close to the surface. A little scratching and digging proved that bedrock was right at the surface in some spots and not more than a couple of feet down in most locations. I automatically knew that a drilled well would be needed. When bedrock is present, drilling is the only sensible option.

You can’t always see what’s likely to be under the ground by looking at the surface. Knowledgeable builders want to know what they are going to get into when drilling wells and digging footings. Many experienced builders won’t give a firm bid until customers or landowners provide them with soils studies. When such studies have not b done, some builders do their own. I’m one such builder.

It is not uncommon for me, or one of my people, to be out digging holes on potential building sites. A posthole digger can reveal a lot about the conditions that exist below the topsoil. Augers and probe rods can also provide some insight into what is likely to be en countered. A probe rod tells you if a lot of rock is present. But, to see the soils, you need a hole. An auger or posthole digger is the best way to get these samples. Augers are often easier to use. A power auger is even better, if you happen to have one.

When you create some test holes, you have a lot more information on which to base your bid decisions. A job that requires a well can only be bid in a few ways. You can guess what is going to be needed, but this is very risky. Digging test holes can give you a very good idea of what types of wells might be suitable. Interviewing well owners on surrounding property can provide a lot of data to help you with your decision. And, hiring soil-testing companies is a great, but expensive, way to find out what you are getting into. Another good way to protect yourself is to have a few well installers walk the land with you so that they can provide solid bids.

Since soils tests are required for land where a septic system is going to be used, the results from these tests can be reviewed to aid in the evaluation of a well type. This, however, is not always a safe way to proceed. Since septic locations are typically at least 100 feet from a well location, ground conditions might be very different. If you are going to rely on tests, the testing should be done at the proposed well site.

Since most builders are not well experts, it’s wise to have well installers make site inspections in order to provide solid bids. If you have three to five bids from reputable well installers, you can feel se cure in the fact that the bid you present a customer is going to be safe. This is the easy way out, but it’s a good way to go.

You should get several firm quotes from well installers. It’s risky to have only one bid. The well installer might be too busy to do your job when its time to start the work. It’s possible that the installer could go out of business before you can request service from the company. As long as you have multiple bids from reputable installers, you should have very little to fear in terms of your well price.


Choosing a well location is not always easy, but it’s important. Many factors can influence the location of a well. The most obvious might be the location of a house. It is not common to place a well beneath a home, so most folks chose a location outside of the foundation area of a home. Septic fields are another prime concern. Septic systems are required to be kept a certain distance from wells. The distance can vary from jurisdiction to jurisdiction. Also, the topography of the land can affect the distance. In addition, the well-drilling rig must be able to get to the site. These large trucks aren’t as maneuverable as a pick-up truck. Picking a place for a well must be done with access in mind.

Appearance can be a factor in choosing a well location. Wells are not pretty, so they usually aren’t welcome in locations where their presence is obvious. A drilled well is easier to hide than a bored well. The difference between a 6-inch well casing and a 3-foot well casing is considerable.

The location of a well also depends on where an expert believes water is going to be found. Few people know for sure where water can be found, but some people have a knack for being right more of ten than not. This brings us to the question of prospecting for water. Is it possible to predict where water can be found? A lot of people think so. Let’s talk about this awhile.

Reading signs to find water

Have you ever heard of reading signs to find water? No, you won’t find a billboard exclaiming “Water Is Here” along with an arrow pointing to the exact spot. However, an experienced eye can detect some natural signs that can reveal data on potential underground water.


Maps can give you a lot of guidance on where water might be found. Some regional authorities maintain records on wells already in existence. Reviewing this historical data can definitely help you pinpoint your well type and location. Unfortunately, there is never any guarantee that water is going to be where you think it's . A neighboring landowner might have a well that's 75 feet deep while your well turns out to be 150 deep. It is, however, likely that wells drilled in close proximity are going to average about the same depth. I’ve seen houses in subdivisions where one house has great well water and the next-door neighbor’s water suffers from an unpleasant sulfur content. Fifty feet can make quite a difference in the depth, quantity, and quality of a well.

Topographical maps show land elevations. You can look at these maps and put many things into perspective. If there is a river or stream in the area, you can plot the position of your property in perspective to the surface water, does this help you? Not necessarily.

My property has a good deal of river frontage. My well location is probably fifty feet, or so, above the river. Yet, my well is over 400 feet deep. I’m not sure why, but I think it has to do with the fact that my well is drilled into bedrock. Water doesn’t run through solid rock very well.

Some maps are helpful, especially the ones that indicate depths and types of wells already in existence. Water does run through rock, but it needs cracks or some other form of access to get into and out of rock. All these factors make it difficult to predict what you are going to find when you attempt to install a well.


Plants can be very good indicators of water availability beneath the ground’s surface. Trees and plants require water. The fact that plants and trees need water might not seem to provide much insight into underground water, but it can. Take cattails as an example. If you see cattails growing, you can count on finding water nearby. It’s suggested that the depth of water in the earth can be predicted, to some extent, by the types of trees and plants in the area.

Supposedly, cane and reed indicate that water is within 10 feet of the ground’s surface. Arrow weed means that water is within 20 feet of the surface. Many other types of plants and trees can indicate the presence of water. From a well-drilling point-of-view, I’m not sure about the accuracy of these predictions. I know that cattails and ferns indicate water is nearby, but I can’t say that it’s going to be potable water or how deep it's in the ground. I suspect, however, that there are some very good ways to predict water by studying the plants and trees.

Since I am not an expert in plants, trees, or finding water, I won’t attempt to fill you with ideas about how to find water at a certain depth just because some particular plant grows in the area. I feel that with enough knowledge and research, a person can probably predict water depths with good accuracy in many cases. If water can be predicted with plants and trees, can it be found with a forked stick? Maybe so.


Dowsing is a subject that can cause a lot of controversy. Some people swear they can find water with nothing more than a forked stick. Can they do it? Sometimes they can. People have successfully located water with what is often called a witching stick. How hard is it to do this? There is a huge amount of underground water in the United States. Someone looking for water might be just as successful with a fireplace poker as with a twig from a willow tree. Since I have no first-hand experience with dowsing, I’m not in a position to make a judgment call on its merits.

I have known builders who hired dowsers to come to job sites and pick locations for wells. They probably always hit water. But then, so have I, and I’ve never used the services of a dowser. Rumor has it that the type of wood used for a divining rod (forked stick) is important. Favorite wood species include peach, willow, hazel and witch hazel. It’s said that since these trees require a lot of water to grow, their wood is ideal for locating water.

I’ve studied the use of divining rods to a minor extent. Rather than forked sticks, people use metal rods to search for gold, water, and other underground treasures. As an amateur treasure hunter, I find it interesting to learn about new ways to locate hidden bounty. A television show about treasure hunting conducted a controlled test of self-proclaimed dowsing experts. The test was controlled over a man made test bed. If my memory is correct, the dowsers did much better identifying water than they did finding gold. Did the testing prove anything? I don’t know, but it was interesting to watch.

In my experience as a builder, I’ve never found a need to hire a professional dowser. You can try their services if you like, but I don’t feel it’s necessary. An experienced well installer who knows the area and has access to maps is probably just as good a bet, maybe better.

High-tech stuff

Some professional water hunters use high-tech equipment. I assume their sophisticated scientific gear works, but I don’t know this to be true. If you were looking for an underground water source to serve a small community, it might be worthwhile to enlist the services of some of these professionals. But, for a single house, I wouldn’t go to the trouble or expense. You are probably ahead if you hire a well driller, on a flat-rate basis, who can guarantee water.

Do a site inspection

It doesn’t take very long to perform a site inspection. Usually an hour or so is all that’s needed. Can you afford to spend thousands of dollars to save an hour or so? I can’t. Site inspections are important. Whether it’s you or your well installer that decides on the type of well that’s needed, someone is going to assume a lot of responsibility. It’s going to cost someone a lot of money if you planned to use a bored well and then found out that a 400-ft drilled well is needed. Customers expect guarantees and fair prices. Your should expect the same from your well installer. While you might win more than you lose by playing the odds, the losses can be very expensive. Someone should definitely perform a site inspection before commitments are made on wells.

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Updated: Tuesday, October 16, 2012 14:43