For more than a year, Newark officials denied the city had a widespread lead problem with its drinking water.
Then, in an abrupt shift last fall, New Jersey’s largest city began giving out water filters to some residents.
On Sunday — two days after a scathing letter from the E.P.A. raised concerns about the safety of the city’s drinking water — officials said they would start offering bottled water to residents.
Gov. Philip D. Murphy of New Jersey and Newark’s mayor, Ras Baraka, said in a joint statement that they would provide bottled water at four local centers, starting as early as Monday afternoon.
“Access to safe drinking water is critically important to our administrations and we take health risks associated with lead in drinking water very seriously,” the statement said.
The decision to provide bottled water — a measure used during the water crisis in Flint, Mich. — came after testing this month showed that water filters provided by the city were not properly removing lead. It was Newark’s strongest effort yet to address the problem and an acknowledgment of the severity of the public health crisis.
Officials in Newark were slow to acknowledge the problem and last October agreed to give away 40,000 water filters across the city of 285,000 people. Like Flint, Newark has a large black population and a high poverty rate.
On Friday, a top official at the E.P.A. sent the city a letter urging officials to provide bottled water to residents with lead pipes “as soon as possible.”
“We are unable at this time to assure Newark residents that their heath is fully protected when drinking tap water filtered through these devices,” the letter said in reference to city-issued water filters.
Mr. Baraka has defended the city’s response and rejected comparisons to the situation in Flint. On Saturday, Mr. Baraka urged pregnant women and young children to use bottled water until additional testing was done, but he did not mention the recommendation from the E.P.A. for all residents with lead pipes to use bottled water.
Critics like the Natural Resources Defense Council have called for the city to offer bottled water.
Erik Olson, the defense council’s senior director for health programs, said Mr. Baraka’s announcement was a good first step, but said the city should offer bottled water to even more residents.
“We’re concerned it might be a temporary thing and we’ll be back to where we started with thousands of citizens in Newark continuing to get water that is contaminated,” Mr. Olson said.
On Saturday, Mr. Baraka acknowledged that the city did not know if there was something wrong with its water filters. He urged residents to run their water for five minutes to clear the system of stagnant water before using a filter.
“We don’t know either way,” Mr. Baraka said. “We don’t have enough information to make that determination.”
A spokesman for the E.P.A. said on Sunday that the city “has not yet formally replied to our letter.” The website NJ.com was the first to report on the letter on Sunday.
Mr. Baraka ran for mayor in 2014 as a populist firebrand to succeed Cory Booker, the United States senator who is running for president. When Mr. Baraka was elected to a second term last year, he won praise for balancing new development with fears about gentrification. But he has also received criticism over the water crisis.
In January, Mr. Baraka called on President Trump to help the city with its lead problems instead of building a border wall. In a letter to the president, Mr. Baraka said it would cost about $70 million to replace lead service lines in Newark.
Mr. Murphy and Mr. Baraka said on Sunday that they would “need support and assistance from the federal government if bottled water is to be provided and distributed to impacted residents.”
On Aug. 6, water samples were taken at two homes in Newark, according to the letter from Peter D. Lopez, a regional administrator at the E.P.A. Several samples of filtered drinking water had lead levels exceeding 15 parts per billion, the federal threshold requiring action.
For nearly a year and a half after high lead levels were first discovered in the water system, Mr. Baraka and other officials blamed aging lead pipes, insisting on the city’s website that the water was “absolutely safe to drink.”
But Newark changed course after a study found that lead was leaching into the water because of ineffective corrosion treatment at the city’s Pequannock plant. Last year, lead levels in more than half the samples tested at homes served by the plant exceeded the 15 parts per billion standard.
For now, bottled water will only be available to residents in the Pequannock service area who have lead service lines and had received filters from the city, according to the statement from Mr. Murphy and Mr. Baraka. The bottled water will be available while officials conduct additional testing.
The Natural Resources Defense Council sued Newark and the state last year, accusing them of violating federal safe drinking water laws. The next court date is Thursday.