Laura Bliss is a staff writer at CityLab, covering transportation and technology. She also authors MapLab, a biweekly newsletter about maps (subscribe here). Her work has appeared in the New York Times, The Atlantic, Los Angeles magazine, and beyond.
Researchers say road salt is causing dangerously high lead levels in the city’s water.
Last summer, after decades of piping in water from Detroit, the city of Flint, Michigan, turned on the valve to its own Flint River. Reporters heralded the new water source for Flint’s 100,000 citizens as a proud symbol of the city’s independence from Detroit. “It will take two days before Flint residents can taste history,” one local news story proclaimed. The local water was toast-worthy at one city ceremony:
[O]fficials raised glasses of water in celebration.
“Individuals shouldn’t notice any difference,” said Steve Busch, Lansing and Jackson district supervisor in the DEQ’s office of drinking water and municipal assistance.
… When [Flint Mayor Dayne] Walling flipped the switch, pumps powered down as water ceased flowing from the 36-inch water main from Detroit.
“There have been a lot of questions from our customers because this is such a major change,” he said. “When the treated river water starts being pumped into the system, we move from plan to reality. The water quality speaks for itself.”
The story now reads as ironic, for Flint’s arrangement is not working out well. Soon after the switch was made, residents began to complain about the taste, smell, and appearance of their water. Problems arose with the disinfectants used to clean it. The city is now in the throes of controversy around the river water’s quality.
Prompted by a concerned citizen, independent researchers from Virginia Tech tested water taken from nearly 300 homes in Flint. In about 20 percent of the samples, they found ‘serious’ levels of lead—15 parts per billion or higher in some homes, which is well above the EPA’s legal limit.
That conflicts with tests the city had done according to the Michigan Department of Environmental Quality’s procedures, which showed the water met safety standards. The city has so far stood by its commitment to Flint River water, stating it “has no problem with cooperating in additional testing.”
According to Marc Edwards, the Virginia Tech team’s lead hydrologist, the problem with Flint River water is that it’s highly corrosive—about 19 times more than Detroit water. That corrosiveness is breaking down old lead pipes and soldering that connect homes to water mains.
Water usually becomes capable of destroying metal when it’s got lots of salt in it. How does salt get into the Flint River? Edwards says it occurs naturally to an extent, but that the big culprit is likely road salt, which is mostly sodium chloride. It’s estimated that about the U.S. uses about 109 pounds of road salt per person every year. Cities actually faced road salt shortages last winter because demand was greater than ever.
“There are many other utilities in the Northeast that have been seeing these rising chloride levels,” says Edwards. “We’re working with utilities that had had no lead problem up until recently. As road salt use rose, it reached a trigger point.”
In Flint, Edwards says, the city was not adding a corrosion inhibitor to the water for “inexplicable” reasons.
Corrosion and lead problems are likely to spread to other utilities nationwide—a product of America’s love affair with road salts, the dismal state of water infrastructure and, of course, rising sea levels.
Edward’s advice to cities? “The first step if you have a lead problem is to tell people so they can protect themselves while you’re working on it,” he says. It seems Flint hasn’t been so forthcoming.