The city began experiencing problems in spring of 2014 after switching its water supply to the Flint River to save money. The corrosive water stripped lead from pipes, elevating levels in drinking and bathing water. The city's children were found to have high levels of lead in their blood, and city officials declared a public health emergency in October.
But state officials knew about the lead problem earlier. An internal state health study from July found high lead levels in Flint children after the 2014 water switch. However, residents weren't notified of the problem until two months later and continued to drink the contaminated water.
Although the city switched back to Detroit's water system, officials are concerned that the damage to the pipes means they will continue leaching lead into the water.
Snyder activated the Michigan National Guard last week to help hand out bottled water and other supplies. President Obama also signed an emergency declaration Saturday that will authorize FEMA to provide water, filters, cartridges and other items to the city for 90 days.