EPA chief: Protective film building up in Flint pipes

Jacob Carah
Special to The Detroit News

Flint — Environmental Protection Agency Administrator Gina McCarthy said the city’s lead levels are dropping as the municipal water system builds up a protective biofilm in the pipes.

McCarthy, who on Tuesday visited Flint for a second time, said the pipes are recoating with a phosphate barrier that prevents lead from leaching into the drinking water. Flint’s system was reconnected to Detroit’s water supply in October, which has corrosion treatment that is healing the more than 8,000 lead service lines.

“Our phosphate levels, for the first time with confidence, are also improving,” McCarthy said.

The biofilm was destroyed after the city’s switched its water source to the Flint River in April 2014 and failed to properly treat the water with corrosion control.

According to EPA data, the overall lead levels are dropping within the water system. McCarthy said it’s encouraging to see the developments from water testing but remains adamant more sampling needs to be done to ensure the “organophosphates are keeping the lead lines intact” so the city can move on to containment and removal of those lines.

“The numbers we’re seeing are good, but I’m not going to tell people anything more than that until I see the data and it’s based on science,” she said.

The EPA will release its most recent findings to the community “near the end of March and that information will be available to the public in April.”

Taking a tour of the Food Bank of Eastern Michigan, McCarthy said Tuesday there is much improvement with the quality of water but more work to be done.

“Yes, Flint is unique, and hopefully will never be repeated again, but we have an obligation to look at our water systems across the U.S. to make sure our current system is being operated correctly,” she said

McCarthy encouraged residents to continue to flush their systems in the morning to move protective chemicals through the system.

“Flush the system for at least a couple minutes, better to do five if you can,” she said.

Remarking on the NSF-certified filters provided to residents, McCarthy said the EPA tested filters with lead-tainted water over 150 parts per billion — the ceiling the filters are rated for — and said they were successful in bringing water to safe levels.

“We have done our due diligence on those filters,” McCarthy said.

Officials were alarmed in January by water samples of unfiltered water from the Michigan Department of Environmental Quality suggested Flint’s lead contamination in parts of the city was stronger than residential faucet filters can handle.

Meanwhile, Mark Durno, supervisory engineer for the EPA, explained Tuesday further steps the agency would take to improve the quality of the city’s water.

“We’ll be making a proposal to the city about a possible flushing program where they do some flushing to get chemicals, like chlorine and orthophosphate, to treat the pipes better distributed throughout the system,” he said.

Durno suggested “dead areas” in the system could benefit by opening up fire hydrants to get water moving.

“In a perfect world, the system would get downsized,” he said.

Also on Tuesday, McCarthy rolled out the work the agency has done on the ground since arriving in Flint. The stats include: knocking on 7,000 doors, passing out 1,575 fact sheets, convening at 90 places of worship, libraries and senior centers. The EPA has a goal of 300 meetings at community centers by April.