Just How Deep Should A Water Well Be? The Answer Isn't Simple

 Just How Deep Should A Water Well Be?

Knowing the depth of a new water well before drilling begin is impossible but data might provide insight


Your new house is almost complete, and you are ready to move to the next step of home ownership, drilling a water well. Standing on terra firma, looking down at your footprints, you find yourself trying to see beneath the surface to where exactly the sweet water awaits.

Figuring out how deep a well must be required through historical records, geologic knowledge, and a good bit of experience. While your well is being drilled, your well water professional will weigh several factors in determining the final depth of your well.

Professionals will need to be familiar with building codes related to wells in your area. These rules include the length of casing required and the proper amount of grout needed on the outside of the well. You will need to supplement the casing and grout with a special cap that keeps animals, surface water, and bacteria from getting into the water from the top.

Water Tables Go Up and Down

Of course, the underground water table rises and falls during different times of the year, depending on the rain and runoff available. Wells have to be deeper than the expected lowest point of the water table, so your water professional will review the historical record of the range of water levels in your area to determine the predicted depth of the well. Even so with this information, the final depth measurement can only be known once the drilling has started.

Rock Formations

In some areas, the aquifer is known as a “low yielding rock formation,” where the recharge is slow, and part of the well will need to have some storage capacity. Your water professional will do the calculations that tell how much water can be stored in the cavity at the bottom of the well.

Drilling a Water Well and Getting Good Water

Other considerations in choosing the area the well will be put in include assessing the quality of the water. Even under the ground, water can be less than good for drinking. Excess sedimentation, excess minerals and even salt water that intrudes can lower the water’s quality. A well driller can case off the water you don’t want. In addition, the USGS, or United States Geological Survey, can provide information about water quality in your region.

Avoiding Water Well Contamination

Contamination can come from surface sites too. Professional drillers will make sure that wells are deep enough to protect the water from being contaminated by bacteria on the ground. Also, a properly built well will include casing, grout, a well cap and a pitless adaptor. A deep well is naturally protective too because as the water travels from where it recharges to the top, that allows time for the bacteria to die.

Once the well is drilled, the pump will be placed at the proper depth. Experts recommend they rest 10 to 20 feet from the bottom of the well. Some pumps come with an automatic switch that turns the pump off if the water line goes too far down. This keeps water from flowing in and bringing more sediment into the cavity. You don’t want sediment.

The use of water wells to access fresh drinkable water is a practice that harkens back thousands of years. But wells are more than a hole in the ground that brings water up. The location where they are drilled, the depth they go to and the way the protect the water are very precise. Make certain you have a qualified professional like the team at Skillings & Sons drill your well so when you turn on that tap you can be sure the water is as clean.