Groundwater pollution may be an overlooked aspect of Arizona water issues

Editor’s Note: This is the third of a five-part series called “KTAR Water Watch,” which will explore the present and future of the water supply across Arizona and metro Phoenix.

PHOENIX — You can’t see it, but how we live impacts it and plays a vital role in almost everything that happens in Arizona.

Groundwater is located deep beneath the surface and stored in aquifers, which are porous rock that contain or transport water.

About 40% of the state’s water supply is underground, with that number likely to increase due to reductions in available water from the Colorado River.

Sarah Porter, director of the Kyl Center for Water Policy at Arizona State University, said the reliance on the resource stems from Arizona’s geography.

“A lot of Arizona does not have a convenient surface water supply, but we did have water in the ground,” Porter said.

An ongoing concern is what would happen if the valuable resource got contaminated.

Thankfully, according to Porter, much of Arizona is regulated to catch dangerous chemicals and pollutants before reaching the water we drink.

Dr. Rebecca Muenich, associate professor of environmental engineering at ASU, points out a different dilemma. Those same standards don’t apply to private wells.

“This is, in turn, a problem because about a third of those wells exceed human health based standards for one or more pollutants,” Muenich said.

Groundwater pollution can come from a myriad of places. It happens when a contaminant either sits on top of the ground or is found in the soil itself and leeches into the aquifers below.

These can come from sources such as industry or agriculture.

“We have a lot of growth happening in Arizona in many sectors, and with that, you know, comes the potential for these sources of contamination to be in the environment and potentially end up in our groundwater resources,” Muenich said.

The Arizona Department of Environmental Quality says about 300,000 people drink private groundwater.

The reach of pollution extends past that. It’s also used for irrigation, livestock and food processing.

“And if we have contaminants moving with that water that we’re using in so many processes and industries, then that can maybe work its way into the health of people,” Muenich said.

One of the more prominent examples of water pollution was here in the United States.

“What happened in Flint, Michigan, was a combination of so many things that went wrong from both an engineering and technical standpoint to political/social issues,” Muenich said.

She says all parts of the world are at risk for possible harm from water quality problems.

“That’s why we have in the U.S. many regulations alongside extensive monitoring programs to try and prevent these occurrences or try to catch them before they become an issue,” Muenich said.

She said Arizona has an existing monitoring program for groundwater basins for multiple pollutants. The state requires permits for industrial operations that may contaminate groundwater.

Arizona also has programs to clean up historically contaminated sites.

Muenich stresses as Arizona continues to experience growth while going through a drought, it’s important to focus on an overlooked aspect of the issue.

“In Arizona, we tend to focus on water quantity for obvious reasons, but if the water we’re left with at the end of the day is of poor quality, it doesn’t really matter,” Muenich said.