DETROIT (CN) – Detroit officials said Wednesday the city will shut off drinking water in all of its schools after testing revealed elevated lead and copper levels in more than half of the 24 buildings that were recently tested.

Nikolai Vitti, superintendent of the Detroit Public Schools Community District, said in a statement that the move was made out of an abundance of caution. He noted that a total of 34 schools have water-quality issues revealed in testing going back two years.

“Although we have no evidence that there are elevated levels of copper or lead in our other schools where we are awaiting test results…I am turning off all drinking water in our schools until a deeper and broader analysis can be conducted to determine the long-term solutions for all schools,” he said.

Vitti added, “I have communicated this decision to the mayor’s office and the mayor and his team are supportive of the decision and intend to require all city charter schools to participate in the same level of water testing as we initiated last year. The mayor’s office plans to partner with us to determine challenges with water quality in our schools and solutions to them.”

The 16 latest school buildings that showed high levels of lead and copper will be shut off immediately while the remainder of the buildings will be shut off by the end of the week, according to the superintendent, who said that water bottles have been provided at the schools until water coolers arrive.

Vitti has had more water-quality testing performed at the schools since the spring without a governmental or legal mandate. He said it was a comprehensive test that covered sinks and water fountains.

There are 106 school buildings in the district.

About 70 miles north of Detroit, Flint still struggles with toxic water cleanup from leeching lead pipes and a brief use of the corrosive Flint River for tap water.