As many as 63 million Americans, or nearly a fifth of the United States, were exposed to potentially unsafe drinking water during the past 10 years, according to USA Today, which cited the findings from a News21 investigation.
The News21 team, consisting of college journalism students and recent graduates, led the investigation into 680,000 water quality violations the Environmental Protection Agency flagged. The study analyzed health-based violations.
Here are six things to know.
1. Problems with contaminated drinking water took, on average, two years to fix.
2. EPA estimates that local water systems will need to invest $384 billion in the next couple decades to ensure water cleanliness.
3. Texas, Oklahoma and California were the top states for EPA water quality violations.
4. Chemicals found in the drinking water included arsenic, chemicals from nearby factories and fecal matter from farms.
5. Drinking water quality is often dependent on the wealth and demographics of a community.
6. Sixty-three percent of Americans are concerned a "great deal" about the safety of their drinking water, according to a Gallup poll released in March.