The water at Center Township Elementary School is safe to drink, officials say.

Butler School District on Monday posted the results of water tests conducted earlier this month to its website.

The results show that the water contains safe levels of metals and inorganics, Jeffrey Mathieson, Center Township principal, wrote in a letter to parents.

The school had temporarily switched to giving out bottled water to students after a teacher spotted “black particles” in the water.

District officials consulted with Gannett Fleming engineers who told them that the particles had been caused by a power outage and were safe. Subsequent water tests did reveal elevated levels of aluminum, copper and iron — which prompted the district to order another set of tests.