Austin's school district has tested the water at all 130 of its campuses to check for its safety. And while the district said it's safe, not everyone agrees.

The testing revealed that one school had lead levels above 15 parts per billion, which is an amount the Environmental Protection Agency (EPA) does consider safe.

Austin Independent School District responded, saying the drinking water is now safe at all schools, according to the EPA's level of acceptability. AISD said one school was found with a water fountain at unsafe levels of lead -- 15 parts per billion -- and was immediately replaced. The district said the replacement was voluntary on their part since there is currently no requirement for any action to be taken.

However, non-profit "Environment Texas" said what the EPA considers acceptable is not, and that it is a legal trigger for water utilities rather than a health-based standard. Environment Texas said that schools should follow the American Academy of Pediatrics' guideline, which recommends keeping water levels below one part per billion. Under that standard, Environment Texas said that 71 percent of Texas schools test positive for lead in drinking water. That's 779 out of 1,088 schools tested.

According to the group, testing found lead in the water above that on part per billion mark at five Austin Independent School District facilities, including Ridgetop Elementary School, Sanchez Elementary School, Widen Elementary School, the Burger Activity Center and Noack Sports Complex.