Letter: Wells and Pumps

Facebooktwittergoogle_plusredditpinterestlinkedintumblr

I’m curious as to if any other readers have had difficulty getting good information on hand pumps? I am not technical by any definition of the word, but here is my situation: I just purchased a homestead in the country with well water. The pump runs by electricity. I have spoken with several well drillers in the area, explaining that I want a hand pump for grid down. The stock answer is “get a generator”. I live in southeastern NC. I understand there can be problems with trying to connect a hand pump to an already existing electrically-powered well. I can afford to have a second well drilled that uses a hand pump. One company mentioned a “deep well jet pump” but indicated it is complex and something about the chlorine that needs to be used and water not being able to rise to the surface if the chlorine level is off(?). Another said the static water level must be at 10-12 feet from the surface, that a 2-inch diameter shaft would not work, and a 4-inch shaft is a “waste of money”. I was also told that a hand pump can only work to a 30-40 foot range, while another company (the jet pump company) said I could get drinkable water at 100 feet and pristine water at 200 feet. I am confused and can’t seem to find any drillers within a 75 mile radius who have any sense of preparedness. Is this a common problem and do you offer any suggestions, especially in terms of geographically-specific help? Thanks. – MB

Hugh Replies: There are two basic kinds of hand pumps in use, and the only difference is where the pump is located. In the normal “pitcher” pump that we think of, the pump valves are located in the body of the pitcher itself. The water is drawn out by means of creating a vacuum in the drop pipe inside the well by the action of the pump. The air pressure will then push the water up the pipe where the pump can push it out of the mouth. The maximum theoretical depth that these pumps work is based on the air pressure. At sea level, that is about 14psi, which equates to about 33ft. Due to loses in the system (friction), and usable flow rates, you will generally find that 24ft is about as high as these kinds of pumps will lift water. They are entirely adequate, if your water table is within that range. If you have a good cased well, you can still be using water from the 200ft level. Your well screen should be towards the bottom of the well and as you draw water off the top of the well, it will be replenished with fresh water from the bottom of the well. Even though your shallow well water may not be good for drinking, the deep water usually will be. This type of hand pump has good flow and can easily generate 20gpm from hand pump action. The Simmons 1160/PM500 is a good example of this type. With this type of pump, you will generally have a powered pump for normal operation. When you lose power, you simply pull the powered pump off and replace it with this pump.

The second type of pump actually has the pump and valves at the bottom of the drafting inlet and is usually connected by a metal or fiberglass rod in the center of the pipe to the handle at the top. These types of pumps actually push the water up the pipe, rather than relying on air pressure. Since they can generate much greater pressure, depths of 100 to 200 feet are realistic, though the volume of flow will generally be much less (usually around 1 to 3 gpm). There are a number of different types that can be used. If you have a submersible electric well pump, you can use the Bison pump inline with your submersible. If you already have a submersible pump, you can run a Simple Pump right alongside if you have a 4” casing. This is the arrangement I am currently using.

A word of caution is in order if you are drilling a new well. If you ask most well drillers how deep you need to go to get good water, they will generally give you a number. (In our area, it is 250ft). If you look at their trucks, that is how much drilling stem they have. They get paid by the foot, and if they can get you to drill deep, it’s good for them. If you have water at 12 feet, ask your county extension where good water is. You will find that in almost all areas of the United States, good water is obtainable at much less depth than a driller will tell you. Of course, you must also balance that with the characteristics of the water table in your area. If you are in a river bottom area, your water table is probably pretty stable. If you are out on the plains, it may vary considerably, and you will want to plan accordingly.

Bookmark the permalink.

Advertisements:


Leave a Reply

Your email address will not be published.
Anonymous comments are allowed, but will be moderated.
Note: Please read our discussion guidlelines before commenting.