Darlene McClendon, a sixth-grade teacher at Eisenhower Elementary School in Flint, said the water crisis has made her worry more about the future of her students. (Brittany Greeson for The Washington Post)

Michigan Attorney General Bill Schuette filed another round of criminal charges Tuesday in  the ongoing water crisis in Flint, the latest action in a nearly year-long investigation to hold accountable those responsible for a disaster that exposed thousands of children to dangerously high lead levels.

Schuette announced felony charges against four people, including two former state-appointed emergency managers who oversaw a disastrous switch of the city’s drinking water source to the Flint River. Darnell Earley, whom Gov. Rick Snyder (R) put in charge of the city’s finances from late 2013 through early 2015, and Gerald Ambrose, who held the emergency manager position through April 2015, could face decades in prison.

Prosecutors allege that the emergency managers conspired with two Flint employees, public works Superintendent Howard Croft and utilities Administrator Daugherty Johnson, to enter into a contract under false pretenses that bound the city to use the river for its drinking water, even though the local water plant was in no condition to properly deliver safe water to residents.

Even after the officials were told repeatedly that the Flint water department wasn’t ready to make the switch in 2014 and that the city should keep getting its water from Detroit, investigators say Earley and Ambrose pushed the change forward in a bid to save money. The decision ultimately exposed children and other residents to lead-tainted water and resulted in the death of a dozen people from Legionnaire’s disease.

“This fixation [on money] has cost lives. This fixation came at the expense of protecting the health and safety of Flint,” Schuette said in a news conference Tuesday. “It’s all about numbers over people, money over health. . . . Flint was a casualty of arrogance, disdain and a failure of management. An absence of accountability.”

The four men charged Tuesday all face felony charges of false pretenses and conspiracy to commit false pretenses. Earley and Ambrose also face charges of willful neglect of duty and misconduct in office.

Investigators have now filed 43 criminal charges against 13 current and former state and local officials.

In April, Schuette announced initial charges against three state and local workers for their roles in the water crisis. That included more than a dozen separate counts against two officials at the Michigan Department of Environmental Quality, as well as a Flint water quality supervisor. They were accused of misconduct in office and tampering with evidence, as well as for willful neglect of duty.

In June, Schuette filed civil charges against two engineering firms that allegedly “botched” their work on the water supply system, contributing to the crisis.

The following month, six more state employees were charged with misconduct in office for their alleged roles in contaminating Flint’s water supply. Those charges, against three Department of Health and Human Services employees and three from the Department of Environmental Quality, included claims that some had hid or disregarded test results showing high lead levels in the blood of Flint residents and had tampered with water test results sent to federal officials.

So far, Schuette said Tuesday, some defendants have entered pleas, while other cases are proceeding toward trial.

The disaster in Flint, a once-thriving industrial city of about 95,000, began nearly three years ago. For decades, the city had used water piped in from Lake Huron, with anti-corrosion chemicals added along the way by Detroit water officials.

In April 2014, with the city under the control of Earley, an emergency manager appointed by the governor, officials followed through on an earlier decision to switch to the Flint River to save money. According to prosecutors, they did so while ignoring “warnings and test results” that the plant was unable to guarantee safe water to residents. The state’s environmental quality agency also failed to ensure that corrosion-control additives were part of the new water supply, which allowed lead and other substances such as iron to leach from aging pipes.

Residents began to complain almost immediately of brown, smelly water that burned their eyes and left them with rashes. Public officials repeatedly issued reassurances that the water was safe. Only after researchers in Flint publicly disclosed tests showing spikes in lead levels in children’s blood did Flint switch back to Detroit water. Even now, more than a year later, the tap water there has not been declared safe to drink, and many city residents are still drinking, bathing and cooking with bottled water.

While investigators  Tuesday said their inquiry is beginning to wind down, they vowed to press on until the reckoning they promised nearly a year ago is complete.

“We’re much closer to the end than we are to the beginning, but we’re not at the end,” said Andrew Arena, the chief investigator in the probe. “There are some people out there right now who know that they’ve done wrong, and they know we’re coming after them. They’re not going to have a very merry Christmas.”

Read more:

Michigan must deliver bottled water to Flint residents, judge rules

‘There will be more to come,’ attorney general vows after criminal charges filed in Flint water crisis

Six more Michigan employees charged with misconduct in Flint water crisis

The EPA’s lead-in-water rule has been faulted for decades. Will Flint hasten a change?