CNN  — 

Michigan’s top prosecutor has called it the biggest case in the state’s history, one that failed Flint families. How did it happen? Here’s how it started and what’s next.

What happened?

To save money, the state switched Flint’s water supply in 2011 from Lake Huron to the notoriously filthy Flint River. When the Michigan Department of Environmental Quality failed to treat the corrosive water, it ate into the city’s iron and lead pipes and leached into the drinking water.

Predictably, people got sick. They complained of skin lesions, memory loss and depression and expressed concerns about Legionnaire’s disease, miscarriage and childhood development.

All the while, officials maintained the water was safe. Former Mayor Dayne Walling famously drank the water in front of local media.

What’s happening now?

The first charges have finally been filed.

Mike Glasgow, who was the supervisor of the Flint treatment plant at the time, is accused of tampering with evidence for changing lead results in an official report and failing to do his job.

Mike Prysby of the Michigan Department of Environmental Quality is accused of authorizing an operating permit for the Flint Water Treatment Plant “knowing the plant would fail to provide safe drinking water.” He’s also accused of misleading federal and county officials and conspiring to manipulate test results with colleague Stephen Busch.

Together, the pair are accused of directing residents to “preflush” their taps before water sample was collected for officials reports – in violation of the Michigan Safe Drinking Act. Finally, Prysby and Busch are accused of not requiring Flint to treat its corrosive river water with chemicals that could have prevented lead from leaching from pipes in violation of the act.

What’s next?

Lawsuits and likely more charges – for whom, exactly, is the million dollar question.

Some Flint residents want to see those at higher levels of state government held accountable, including Gov. Rick Snyder.

On Wednesday, Attorney General Bill Schuette sidestepped questions about possible charges against Snyder. But he said the first round of criminal counts are just the beginning and that more would come.

To quote him directly, “Stay tuned.”