What is the purpose of well casing?

• A. To filter the water
• B. To decorate the well
• C. Protect the water being drawn into the well from contamination & support the structure of the well
• D. To increase water pressure

Answer: (C)

Well casing is used to protect the water supply and support the well itself. It is a pipe that lines the drilled borehole, keeping the surrounding soil from caving in and creating a barrier between the groundwater and surface or near-surface materials. This barrier helps prevent surface water and contaminants from marching down into the aquifer, preserving water quality. Properly installed casing also helps isolate the water-bearing formation so the water you draw comes from the intended source rather than from other layers. It doesn’t filter water—that requires screens or filtration equipment. It doesn’t increase water pressure by itself—the pressure comes from the pump and the hydraulic properties of the aquifer.