In my last column, I described some methods to test-pump the fictional well I had been drilling for several months. As I said then, we really should have developed the well first and then done the test-pumping, so the procedure that I am writing about is somewhat backwards. In larger-capacity wells – irrigation, commercial, municipal and industrial – development may be a requirement, and a charge for that would be included in the bid price. In many domestic wells, however, the finished well merely is test-pumped, and while this may yield a satisfactory product, a properly developed well will be better both for the drilling contractor and the well owner.

Some drillers believe that just pumping a well at a capacity greater than it normally will be pumped is a sufficient development. With this, I disagree. The flow of the water into the well must be reversed to loosen fine material that then can be brought into the well and removed to waste. Some formations also will contain minor amounts of native clays, and these really will gum up the works, resulting in a much-lowered capacity well. Before I describe several development methods that I have used with varying degrees of success, I give you a word of caution. Don’t ever presume that giving an effective development very far out from the borehole or the well screen is going to be easy – it is not, due to a lot of factors, some of which I doubt anybody understands.

A popular development method used in my area is the surge block. This is a sandwich-like device, the cross section of which looks like a double-decker hamburger. The bun portion at top, middle and bottom is constructed of steel plate, and the two burger portions (sometimes just a single burger, but usually a double) are sandwiched between the buns. Our “sandwich” is compressed together, using a large bolt or pipe thread in the center, or machine bolts spaced evenly some distance from the center. In actuality, our “hamburgers” are made of rubber belting or other reinforced rubber material and sized to fit rather tightly in whatever size casing we have in the well to be developed.

The surge block is attached to our drill stem in place of the drill bit and lowered into the well below the static level. The spudding motion is started, and usually run more slowly than the drilling motion. Sometimes this action will drive water from the well, and some external water has to be added from time to time. It is a good idea to run the surge block for a few minutes on the first trial, and then remove the tools and go down inside the well screen with a flat bottom bailer and remove any material that has come into the screen. If the screen is full or nearly full, we can run the block a second, third or more times until we don’t get much material in the screen, at which point we’ve done about all we can do with this method. Personally, I never had a lot of really good luck using the surge-block method, but I do know drillers who swear by it.

Another method that I have used again with mixed results is to use a tool called a jetter, consisting of a short length of pipe that will go inside the screen with its bottom plugged and a series of small-diameter holes drilled through the pipe walls. This tool is lowered into the screen on drop pipe, and the pipe is connected to a high-pressured pump. An external water source feeds the pump, and starting at the extreme bottom of the screen, the tool is rotated back and forth by hand and raised an inch or so at a time until the entire screen has been jetted, or the screen becomes full of sand. The tool then is removed, and the screen bailed out clean. A good high-pressure pump is necessary for this method to work successfully, as we need a high velocity of water coming out of our so-called nozzles.

In practice, I had mixed results with this system, too, perhaps because the pump I was using could not perform to the level needed. The late Bill Anderson, long-time employee of the Johnson Screen Co. of St. Paul, Minn., who, in my opinion, was a genuine expert on the subject of well screens and well performance, once told me that if you had but one method to use in well development, this jetting method was the one. Bill is gone now and greatly missed by his friends, so we will take his statement to be an accurate one.

In the area of Michigan where I have drilled all my life, our water-bearing formations sometimes contain enough native clay to be a problem. The best method I found for developing wells made in these formations is to use phosphates. These products are available through the companies that supply bentonite and other drilling products. The method I used was to mix some phosphate product, which I believe was sodium tri-phosphate or sodium tetra-phosphate – don’t quote me on that; I may be wrong – with fresh water in a tank using a ditch pump. The phosphates are very difficult to mix with water, and the material gets very gummy when it is wet. With patience, though, it could be mixed with several hundred gallons of water, and then pumped through a drop pipe into the well screen and out into the formation.

A downside of this method is that the solution needs to soak in the well at least overnight and, if possible, for a couple days. Surging the well right after injection of the solution seemed to help a lot. I even had a Rube Goldberg pumping system that worked pretty darn well. Rube Goldberg, for you younger readers, was a cartoonist from many years ago who was famous for devising and drawing up extremely complicated systems to perform basically simple tasks. My system consisted of a surge block made of cup leathers the size of the casing, one up and one down, and attached near the bottom of a drop pipe. I usually put an extension down in the screen to pump any fines brought into it out to the surface. A plunger is run into the drop pipe on a smaller pump rod as described in my May 2009 article, and the whole assembly is supported on top of the casing with a coil-type car spring, and moves up and down in rhythm with the pumping stroke. In effect, I have a surge block and a pumping system all in one. When I want just to test the well, I remove the car spring and, of course, the surging stops, and I can pump the well clear. A further downside of this method was that there was a lot of work involved in setting it up and tearing it down, but the results sometimes were spectacular and worth the time spent.

With this last system, I have had some total failures, but more times than not, I have seen a big improvement and the difference between a successful well and a failure. In one case, I improved the capacity of the well by a factor 12; that is, it went from about 2 gallons a minute to 25 gallons a minute. This brings up a good final point. Sometimes, no matter what you try, nor how many methods, nothing works, and you end up having to go deeper or perhaps even move. Such are the frustrations of being a water well contractor.

I’m sure many of you have your own favorite way of development. If you need to do some well development and are unsure of what method to use, talk with other contractors in your area or utilize one of several good books that discuss this subject, which are available to our industry. I hope I have given my loyal readers some ideas, and jogged the memory of others. The snows of a couple columns ago now are only an unpleasant memory, and I need to quit writing, warm up my John Deere and mow 2.5 acres of grass. My best to all of you.