Which type of well is most commonly used for public water supply systems?

The most commonly used type of well for public water supply systems is the drilled well. Drilled wells are constructed using specialized drilling equipment that creates a narrow, deep hole in the ground, allowing access to aquifers located at varying depths. This method provides several advantages that make drilled wells particularly suitable for public water supply systems.

Drilled wells can reach aquifers that are not accessible by other well types, ensuring that the water source is sufficient and reliable. They have a smaller diameter compared to bored wells, which allows for deeper penetration into more productive aquifers, often yielding higher quality and quantity of water. Additionally, the drilling process allows for precise location selection, helping to avoid areas prone to contamination.

In contrast, bored wells involve an excavation and are typically shallower, making them less efficient for public supply where a larger volume and higher quality of water is required. Artesian wells rely on natural pressure in confined aquifers, but such conditions are not available everywhere. Pump wells, while a general term that can include various styles of wells, are not specific to any well construction type or its suitability for public supply. Therefore, the context of well type and its ability to provide a reliable public water source distinctly points to drilled wells as the most common choice.