Drawdown in a pumped well is observed as

• A. An increase in water table
• B. A rebound in groundwater after pumping stops
• C. No change in aquifer pressure
• D. A drop in water table due to pumping

Answer: (D)

When you pump water from a well, you remove water faster than it can be renewed, causing the hydraulic head near the well to fall. This downward movement of the water level—in an unconfined aquifer, a lower water table; in a confined aquifer, a lower potentiometric surface—is called drawdown. It typically forms a cone of depression that expands as pumping continues. When pumping stops, recharge causes the water level to rise again toward its original level.

So the observed change during pumping is a drop in the water table due to pumping. The other ideas describe recharge (water table rising), recovery after pumping (not during pumping), or no change in pressure (pumping by definition alters pressure/head).