In what scenario might the specific capacity of a well be reduced?

The specific capacity of a well, which is a measure of the ability of the well to provide water, can indeed be reduced due to increases in well loss. Well loss occurs when there is energy or head loss encountered while water is being pumped from the well. This can be caused by factors such as the clogging of well screens, the development of sediment at the well bore, or any obstructions in the flow path that restrict water movement. When well loss increases, it indicates that more energy is being used to overcome this resistance, leading to a decrease in the effective yield of the well, and resulting in a lower specific capacity.

In contrast, increasing the diameter of a well generally improves its capacity by allowing for greater water flow. If drawdown decreases, this often indicates that the well is operating efficiently and can maintain a higher specific capacity. When an aquifer becomes confined, the water pressure usually increases, which can enhance the performance of the well, as confined aquifers tend to have higher hydraulic heads. Thus, an increase in well loss is the primary factor leading to a reduction in specific capacity.