Which statement about drilled wells is true?

• A. They are the most common method of well construction.
• B. They are the least common method.
• C. They require no drilling.
• D. They cannot be used in Wisconsin.

Answer: (A)

Drilled wells are the most common method of well construction because they can reach deeper, more reliable groundwater supplies and can be protected from surface contamination through proper casing and sealing. They’re drilled with a rig, then a casing is installed and grouted to seal the annulus, and a screen is placed at the aquifer interface to filter water. This setup typically provides stronger, longer-lasting yields and better water quality protection, which is why drilled wells are preferred for many water systems, including larger municipal and private wells.

The other statements don’t fit: drilled wells do require drilling, so they aren’t “no drilling.” They’re not the least common method—there are shallower dug or driven wells, but drilled wells are more widely used in many settings. And they can be used in Wisconsin, so the claim that they cannot is incorrect.