When asking someone “where does water come from?” the reply typically depends on that person’s stage in life. Typically, a child will answer, “the sink,” or “the sky.” After a little more education, the answer may involve reservoirs and evaporation. The older the individual, the more sophisticated the answer. However, most answers—even from fairly well-versed adults—still usually exclude one of our most vital, and largest, sources for potable water: groundwater.
Most people are well aware of surface water as a source because it is one they can see in lakes, streams, rivers and reservoirs. What you may not realize, however, is that surface water is not the main source for drinkable water. In fact, even though Earth is covered 70 percent by water, only 2.5 percent of it is fresh, and only 1 percent of that freshwater is easily accessible. When you exclude water from oceans and in frozen forms such glaciers, the overwhelming majority of freshwater resides in groundwater sources. Even though we can’t see it, we can’t get along without it either!
The “life” of groundwater varies greatly. Some can be trapped beneath the surface for mere decades, or it could be millions of years. It can be found very near the surface of the earth, or tens-of-thousands of feet deep. The quality of groundwater varies too. Quality depends on the type and number of “natural filters” the water passes through on its way to its final resting place (i.e. the aquifers) before it’s pumped into service.
It’s important to recognize the benefits of both surface water and groundwater, and implement processes to maximize the utility of each as a means to serve communities as well as advance sustainability goals. For example, at American Water, our assets across the U.S. include 1,100 groundwater wells, 500 groundwater treatment plants, 1,400 pumping stations, 81 surface water treatment plants, and more. We pull water from the sources that are most readily available and plentiful, as well as offer the most efficient usage, depending on the community being served.
Whether its source is a nearby stream or miles below the ground, the water emerging from your tap has been through a long and complex journey that certainly merits our respect and appreciation!