Enlarge / Drink with caution. (credit: Getty | Yoko Inoue)

Students returning to school in Detroit next week will find their water fountains entirely shut off over concerns of elevated lead and copper levels—something that federal lawmakers say is part of a “disturbing and unacceptable” nationwide issue.

The decision to shut off the drinking water in Detroit was based on a first round of results from testing that the school district carried out in its 106 schools earlier this year. The results from just 24 schools so far surfaced 16 that had water sources tainted with excessive levels of lead, copper, or both. For instance, tests at the district’s Academy of the Americas Elementary school found a kitchen and drinking faucet in a basement cafeteria that had lead levels of 182 micrograms per liter (ug/L) and 154 ug/L, respectively. Those are more than ten times the Environmental Protection Agency’s recommended limit of 15 ug/L. The full testing results can be found here.

Nikolai Vitti, superintendent of the Detroit Public Schools Community District (DPSCD), announced the shutoff Wednesday. In a statement to the Detroit Free Press, Vitti explained: