The security of our drinking water should always be a top priority, but the ease of access to it lulls us into a false sense of security. Turn on the tap, and fresh, clear water pours out in a seemingly inexhaustible supply.
Contamination incidents are rare, considering the scale of the water delivery system in the United States. While it is true that millions of Americans are exposed to poor-quality drinking water, most of the population has access to on-demand clean drinking water.
There are two primary drinking water sources in the United States, groundwater and surface water.
Groundwater sources come from underground aquifers, naturally occurring layers of porous rock, sand, or gravel that hold water. Groundwater is generally less susceptible to contamination than surface water but still requires treatment and monitoring.
Surface water sources include rivers, lakes, and reservoirs, which local or state governments generally manage. Surface water is treated to remove contaminants and disinfected before being distributed to homes and businesses for drinking.
Regarding contamination, surface water is much more susceptible than groundwater because it sits on the surface rather than underground. Some notable contamination sources are industrial activity, mining, sewage overflows, agricultural activity, and accidents.
