What is an artesian well?

What is an artesian well?

• A. A natural spring with no borehole
• B. A water tower on a hill
• C. Drill into confined aquifers and use pressure to bring water to ground level
• D. Drill into unconfined aquifers with no pressure

Answer: (C)

An artesian well relies on natural pressure in a confined aquifer to bring water to the surface. The aquifer is trapped between impermeable layers, and its recharge area is higher in elevation, creating a hydraulic head. When you drill into that pressurized layer, the water is forced up the borehole by the stored pressure, sometimes reaching ground level without any pumping. This is different from drilling into an unconfined aquifer, which lacks that sustained pressure, and from a natural spring or a storage structure like a water tower, which rely on different mechanisms. So the essence is tapping a confined aquifer under pressure to raise water to the surface.

An artesian well relies on natural pressure in a confined aquifer to bring water to the surface. The aquifer is trapped between impermeable layers, and its recharge area is higher in elevation, creating a hydraulic head. When you drill into that pressurized layer, the water is forced up the borehole by the stored pressure, sometimes reaching ground level without any pumping. This is different from drilling into an unconfined aquifer, which lacks that sustained pressure, and from a natural spring or a storage structure like a water tower, which rely on different mechanisms. So the essence is tapping a confined aquifer under pressure to raise water to the surface.