What characterizes a "flowing artesian well"?

A flowing artesian well is characterized by the ability of groundwater to flow to the surface without the need for any mechanical pumping. This phenomenon occurs when the water is under enough natural pressure in the confined aquifer, which is typically surrounded by impermeable layers of rock or sediment. This pressure forces the water upward, allowing it to emerge at the surface in a continuous flow, often creating a visual spectacle.

In this context, the other choices do not accurately depict the characteristics of a flowing artesian well. Manual pumps are associated with various types of wells that require human intervention for water extraction, but this is contrary to the nature of a flowing artesian well, which relies on natural pressure. Similarly, while some wells may use electrical power to assist in water extraction, a flowing artesian well operates independently of such systems due to the natural flow of water. Lastly, the assertion that a flowing artesian well is always dry is incorrect, as it contradicts the essential defining feature, which is the presence of water flowing to the surface under pressure.