The National Guard has arrived in Flint, Michigan, passing out bottled water and filters in an effort to protect residents from the city’s tainted water supply. Photograph by Brittany Greeson / The New York Times / Redux

Even before the drinking water in Flint, Michigan, was found to be tainted with lead—before water from some areas tested at more than twice the level considered to be toxic waste, and public-health officials said that every last child in the city should be treated as if the child had been poisoned—the governor’s office knew that the water was discolored, tasted bad, smelled strange, and was rife with “organic matter.” They knew, as one memo sent to Governor Rick Snyder in February, 2015, noted, that “residents have attended meetings with jugs of brownish water.” Officials figured that a reason it looked that way was the presence of rust. And they thought that was just fine. They wished, in fact, that the residents would realize how good they had it, when it came to the water’s substance, and stop complaining about its style. Various safe-water laws, the February memo said, “ensure that water is safe to drink. The act does not regulate aesthetic values of water.” The “aesthetics” (the word comes up several times in e-mails about Flint, which the governor released Tuesday night under pressure) were bad because “it’s the Flint River”; “the system is old”; “Flint is old”—the water, in a word, fit their picture of the city, in which about forty per cent of its hundred thousand people lived below the poverty line (and more than half are black). Until April, 2014, Flint had been part of Detroit’s water system, which had Lake Huron as its source. It was scheduled to be connected to a new pipeline in 2016 or 2017, which would save money; Flint is in such desperate financial straits that it was under the oversight of an Emergency Manager. When that manager felt he couldn’t negotiate a low enough price for Detroit water in the interim, the city was left with the option of drinking from the river that ran by it, and past its active and derelict factories, and had been last regularly used decades before. The city would treat the water itself. All the city had to do was pass a few tests; as long as it did, it didn’t matter if the residents were, in effect, drinking dirt. But then, almost immediately, the water began to fail the tests. In August, 2014, and again that September, the water was found to have unacceptably high levels of fecal coliform bacteria, and specifically E. coli. Certain neighborhoods were instructed to boil their water, while the city added chlorine to the supply to disinfect it. It took a lot of chlorine—and that may be where Flint’s troubles really began. (NBC has a timeline of the crisis.) The city’s water managers, unaccountably, seem not to have added any anti-corrosion agents to the water. Nor did they check for corrosion issues in a way they ought to have for a city Flint’s size. (In a remarkable memo a year later, Brad Wurfel, the spokesman of the state’s Department of Environmental Quality, said that the staff had “made a mistake,” and followed the wrong protocol.) By October, 2014, General Motors had announced that it would no longer use the water, because it was corroding its equipment. It was also—and this should have been entirely predictable—eating into the lead pipes that delivered the water to people’s homes, causing them to crumble into the water. Flint is old, and its water system took decades to build. It took only months of cheap, corrosive water to mangle and perhaps permanently destroy it.

Still, the memos from the governor’s office continued to dismiss “the rusty factor” as aesthetic. It might not be good enough for G.M.’s machines, but it was fine for people. The water, as the governor’s office told the public, was still, passing the tests—except in the case of one known carcinogen, TTHM, which was produced by the interaction of chlorine and that “organic matter.” The water wasn’t passing those tests, but it was close enough, and, anyway, since TTHM caused cancer after long exposure, but not within the few years people in Flint were being asked to drink it. The TTHM regulations, a memo to the governor noted, were only estimated to prevent two hundred and eighty bladder-cancer cases each year, “out of more than 330 million people,” and so “it’s not like an imminent threat to public health.” The exchanges in the governor’s office continued to center around how to get one simple message out to the people of Flint: “residents should feel confident that their water is safe to drink unless the DEQ or City notifies them otherwise.”

The memos note that there are plenty of contaminants that the tests don’t look for: E. coli was a particular health hazard, but it should have been a proxy, a sign, like the “aesthetic” issues, that water as dirty as that might have other problems, too. The state and city seem to have ignored that basic lesson of epidemiology—they didn’t seem to register until recently, for example, that there had also been a spike in cases of Legionnaire’s Disease in Flint, which might also have had something to do with the water. Ten people died in that outbreak.

Lead is an imminent and persistent threat to public health. It can cause miscarriages and the births of babies who are too small. Children whose developing brains are exposed to lead can have developmental delays and disabilities for their entire lives. Older people can suffer memory loss, weight loss, circulation problems, behavioral problems; they can feel sick and exhausted. Lead stays in your bones even once it leaves your blood. And there were soon signs that the people in Flint were drinking lead. They weren’t told to stop using the water; indeed, for months, the opposite was the case.

Residents were not only reporting that their water seemed strange. They were reporting that they were sick, had rashes, that their entire bodies were weak. The various Michigan authorities continued to report that they couldn’t find anything unusual—certainly not lead, except maybe some “seasonal” spikes, or statistical flukes. At most, people should let their water run for a while before using it. And yet, in February, 2015—a year ago—an E.P.A. water expert named Miguel Del Toral sent the Michigan D.E.Q. a memo saying that it might be testing the wrong way. “Folks tend to discount these values as anomalies, but particulate lead release is a normal part of the corrosion process and it is universal (common) in all systems,” he wrote. Flint’s habit of “pre-flushing the tap” the night before samples were collected might be skewing things. Del Toral continued, “My point on that was that people are exposed to the particulate lead on a daily basis, but the particulate lead is being flushed away before collecting compliance samples which provides false assurance to residents about the true lead levels in the water.”

The question going forward is whether Michigan authorities deliberately gamed their testing protocol to overlook the lead that they should at least have suspected was there. Under the rules, the lead level would be judged unacceptable if ten per cent of samples the water authorities collected show more than fifteen parts per billion. In June, 2015, the Detroit Free Press examined documents on the testing obtained by the A.C.L.U.; the paper reported that after Flint had collected only thirty-nine of an expected hundred samples, a D.E.Q. official wrote to let city officials know that those samples were looking high. Somewhat ambiguously, he expressed “hope” that the rest of the samples would be “below the AL,” or action level, for lead. Going above that level would put the department in the position of having to do something. The samples are supposed to come from around the city and reflect a judgment about what homes might be at risk. Instead, for whatever reason, as the Free Press noted, a quarter of the remaining samples “came from a single stretch of Flushing Road in Flint,” which had a water-main section only a few years old. “Not surprisingly, all of those samples measured very low for lead,” the paper reported. And the testers still got the numbers under the acceptable level only by throwing out one sample that was extraordinarily high—over a hundred parts per billion. They later said, bizarrely, that it was because the household used a filter, which would, if anything, suggest that the lead there was even higher.