The most common way to withdraw groundwater is from a well. A well is a hole that is dug, driven or drilled into an aquifer. A pipe and a pump are used to pull water out of the ground. Public drinking water wells and private homeowner wells are similarly constructed, with a few important differences. A Public Water

Supply (PWS) well is generally larger in diameter since greater quantities of water are required to be withdrawn. A PWS well also has a longer screen (openings in the well to allow for water to flow) to maximize the amount of water that can be withdrawn. More importantly, a PWS well’s location and depth are specifically chosen to maximize the quality and quantity of water accessible.