When people fill their glasses with water from the tap, they may not stop and think about where that water is coming from before taking a sip.
Delaware County gets its drinking water from both ground and surface water taken from the White River and Prairie Creek Reservoir. While both water sources end up in people’s drinking glasses, the water qualities differs depending on where it came from.
Ground water includes any water found underground, such as water in the soil and aquifers. Surface water is above ground and found in the form of lakes, streams and rivers.
A big distinction between ground and surface water is how they are managed on the regulatory level, said Lee Florea, an assistant professor of geological sciences at Ball State University
“The EPA and the Clean Water Act primarily deal with surface water, and then you have the Safe Drinking Water Act which primarily deals with ground water,” Florea said.
The Environmental Protection Agency sets standards that limit contaminants in drinking water to protect the public’s health while the Clean Water Act regulates the pollutants that are put into water. The Safe Drinking Water Act protects water quality from the source to the tap.
While there are geological differences between ground and surface water, the chemical differences depend on location, Florea said.
“Surface water and ground water have completely different chemistries around the nation depending upon the underlying soils and geology are like,” Florea said. “So if you have water running straight off of a surface into a stream and flowing down through the stream without much interaction with soil or rocks, then the chemistry is going to be very much like the rain that landed on that surface.
Generally, what you see is that the longer [water] flows along whatever path that is, the more it is going to pick up qualities that reflect the chemical interactions with the rock and soils that it’s touching.”
When it comes to drinking water, there are several factors that go into the quality of the water. The greatest health risk with surface water contamination is disease-causing microorganisms, such as bacteria and viruses. These microorganisms generally come from human and animal waste.
Ground water health risks depend on how deep in the ground the water is. Similar to surface water, microorganisms are the main risk the closer to the surface the water is. Deeper ground water that has been kept contained could be disease free but still have chemicals that need to be removed before it’s safe to drink.
While all water goes through specific treatment processes, it is important to know where the tap water came from to assess the quality and safety of the source.
The White River is one of Delaware County’s main sources of drinking water along with Prairie Creek Reservoir.