by Marc Santora and David W. Chen, originally posted on March 11, 2016

In August 2014, as 35,000 students prepared to return to Newark’s public schools, Keith Barton, the managing director of operations for the district, sent a memo with an urgent message to all principals, custodians and building managers: Before anyone drank from the water fountains, they should run the water for at least 30 seconds.

Mr. Barton directed custodians to run and flush every water fountain for two minutes before school started each day, and to tell cafeteria workers to run and flush cold water faucets in kitchens for two minutes before preparing food.

The memo, he wrote, was part of an effort “to reduce the risk of possible lead contamination.”

That effort failed.

The potential danger of lead exposure was something school officials in Newark had been aware of for years, and the district had installed lead-reduction filters on water fountains and kitchen prep sinks, particularly in schools built before 2006, according to Mr. Barton’s memo.

But it took a crisis in Flint, Mich., to focus attention on the issue of lead contamination in Newark, New Jersey’s largest city.

In Flint, the revelation that a series of political decisions and cost-cutting measures had exposed tens of thousands of children to dangerously high lead levels, thrust the dangers of childhood lead poisoning to the center of a national conversation.

While health experts said that the situation in Flint was much worse than the one facing Newark, the sudden closing of school district taps was a stark reminder that lead remains a continuing problem in many communities.

In 2002, for example, tests showed dangerously high lead levels in schools in Camden, N.J. Fourteen years later, the city’s schools are still relying on bottled water, at an annual cost to the state of $75,000.

Like many other Newark parents, Vanessa Gentleman-Cheatham, 35, said she was both terrified and confused by the lead findings in the city’s schools.

She has three children — ages 7, 6 and 4 — who attend Ivy Hill Elementary School, where the taps were turned off. There, and at the other 29 affected schools, children and employees have been given bottled water to drink instead.

“It’s scary; we trust the school system with our kids every day,” Ms. Gentleman-Cheatham said outside the school on Friday. “How long,” she asked, had her children “been drinking this water before they found out?”

Her question is one of several that officials have yet to answer. While the water at Newark school buildings is tested annually, the New York public radio station WNYC reported on Thursday that district officials were unsure whether samples gathered in previous years had been checked for lead.

In a statement on Friday, the school district and the state Environmental Protection Department said that the state agency had obtained lead-test data from the school system going back to the 2012-13 school year and would begin to analyze it. The results of that analysis are expected next week.

New testing of the water in all of the district’s schools would also begin next week, the statement said, starting with the 30 affected schools and including “every faucet or fountain in a school building where people can take a drink of water and every food preparation sink.” The federal Environmental Protection Agency is also being consulted.

The statement also said lead had not been found in the Newark Water Department’s source water, meaning the broader public was not at risk.

“In the vast majority of cases where lead is found in drinking water, it enters through the water delivery system itself when it leaches from either lead pipes, household fixtures containing lead, or lead solder,” said the statement, which was released by the state environmental department, which performs the testing.

But Ms. Gentleman-Cheatham had been so unsettled by the news that she told her children not to drink the tap water at the family’s house in Newark. She was afraid it was all contaminated. She said she had chosen to buy bottled water, an unexpected cost that ate into her family budget.

An annual report on lead poisoning issued in 2014 by the state’s Health Department found that Newark led every other large municipality in the number of children under the age of 6 with elevated levels of lead in their blood, as well as the greatest increase in lead poisoning reported from 2013 to 2014.

Even before the water was turned off in the 30 city schools, state lawmakers held hearings about the dangers facing children in the state because of exposure to the contaminant in their homes, where lead-based paint may still remain.

“You can spend money now, or you can spend later,” Staci Berger, president and chief executive officer for the Housing and Community Development Network of New Jersey, told lawmakers according to the online publication New Jersey Spotlight. “We can absolutely fix this if we put the resources into it.”

Dr. Irwin Redlener, president of the Children’s Health Fund and a professor at the Mailman School of Public Health at Columbia University, said that lead in drinking water was a problem with immediate health consequences, especially for children, but that the recent revelations about contamination offered another ominous warning about the general state of the country’s infrastructure.

“Lead exposure is most dangerous in terms of long-term consequences when it occurs during the most critical phases of brain growth, that is in the earlier years,” he said. “My question is: In addition to schools, are localities testing water systems going to day care centers — official and otherwise — and preschools?”

State officials did not reply to requests for more information about whether they were testing at other sites.

Jeff Tittel, director of the New Jersey Sierra Club, which obtained a copy of the 2014 school memo written by Mr. Barton, said it was evidence that the school leadership had failed.

“We now know that the Newark school leadership, just like in Flint, knew that there was a problem with lead in the water,” Mr. Tittel said. “A year and a half ago, they sent out this memo to everyone in the school system with protocols on lead in drinking water and fountains.”

It should have been “a wake-up call for action,” he said.