In a screened well, where does your water come from? Scroll down for a hint...
No, we do not get our water from Lake Michigan or Lake Superior! Look at the sand, though. Have you ever watched a wave recede and the thousands of gallons of water that were just there vanished?
If you were to look at a lot of the sand and gravel that we have here in Wisconsin, you would see something similar to this beautiful picture at the right. Rounded particles of varying sizes that have been worn smooth by glaciers and water flow. There is a lot of space in between those particles and, if you are into the static water level, those spaces are filled with water instead of air.
Which is exactly the type of formation that we are looking for. You see, they make coffee cups and cereal bowls out of clay because water does not go through it.
Instead, find a nice, coarse sand and gravel formation (if one exists!) and develop the fine sand out with a combination of air and water until the water flows freely into the well as quickly as you wish to pump it out!
AVAILABLE WATER SUPPLY and Expected Life Span (SCREEN):
In a sand and gravel formation well, you generally need a screen to keep the sand out. (Not all screens are stainless steel! You should ask!! But that is what we will use unless we discuss it with you first.)
The amount of water that can pass through the screen as well of the screens expected life span---or how long it takes to plug up---depends a great deal, among other things, on how much open area is available on the screen, what the chemistry of the aquifer water is, how thoroughly was the well developed, etc..
OK, so bigger is better, right? Well, yes and no. You want the largest slot screen that the formation will comfortably sustain. We are pretty good at finding that balance. See at right for charts detailing slot size and why it is important.
PVC Well Screen Information... Unless used as a liner for a 6" well, the PVC well for potable use will always be a screened well. There are formations were the gravel is so coarse that screens are not necessary but those locations are not widespread. Check out those two charts above for more information.