CPS CEO Forrest Claypool said all schools were being tested for lead in the water out of an "abundance of caution." View Full Caption DNAinfo/Ted Cox

THE LOOP — All Chicago Public Schools will be tested for lead in the water after Tanner Elementary on the South Side tested positive while part of a pilot program.

CPS Chief Executive Officer Forrest Claypool emphasized Friday afternoon that 31 of 32 schools passed a pilot testing program brought on by concerns stemming from lead poisoning in Flint, Mich. According to Claypool, 25 of the schools had no lead whatsoever in the water, and six others met federal standards for the presence of lead in water.

Claypool said the testing was being expanded to all schools out of an "abundance of caution" and that they'd be "testing every faucet and water fountain."

Yet three fountains at Tanner Elementary, 7350 S. Evans Ave., tested positive, and all the school fountains have been shut down. Water coolers have been brought in while additional testing is conducted. CPS has planned a meeting with Tanner parents on Tuesday and sent home a letter to parents Friday.

Water Commissioner Barrett Murphy says his department is capable of handling requests for lead testing citywide. View Full Caption DNAinfo/Ted Cox

According to Claypool, water had been recently shut off at the school "for several days" and may have contributed to the presence of lead. Yet it could also have been that these three fountains were old and infrequently used.

"I can't speak specifically" to the cause, said Barrett Murphy, commissioner of the Department of Water Management, who attended Friday's news conference at CPS headquarters. He said Chicago water is treated with a phosphate to coat pipes and prevent lead from "leaching" out of lead pipes and into water, and that shutting water off so it stands in pipes can make that deterrent ineffective.

Claypool announced plans to test all Chicago schools before the end of the school year, starting with 250 schools built before new regulations on lead pipes took effect in 1986.

"Our water supply is safe and pure," said Health Commissioner Julie Morita. "This is an isolated situation involving a small number of fountains at one school."

Morita insisted lead paint was much more of a health concern than lead in the Chicago water supply. "Chicago is not Flint," she said, pointing to the city's Lake Michigan water supply. She did allow, however, that "it's reasonable to test and reassure our residents the water is safe."

Murphy acknowledged that his department had received increased requests to have home water supplies tested. He confirmed the department had received requests for 400 test kits, with 300 sent out. "We've received some of them back already, and we're in the midst of testing them now," he said. Yet he maintained his department was capable of meeting increased requests for testing, even after the Tanner Elementary finding is sure to worry some residents.

Asked about the price of testing the entire district, Claypool said, "It doesn't matter," that the water would be tested no matter the cost. Yet he estimated it would run "several hundred thousands of dollars."

CPS planned to post the test results from the pilot program for 32 schools at the end of the day at cps.edu/leadtesting.

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