<Li> Fifteen criminal indictments </Li> <Tr> <Th> Deaths </Th> <Td> 15 </Td> </Tr> <P> The Flint water crisis began in 2014 when the drinking water source for the city of Flint, Michigan was changed to the Flint River . Due to insufficient water treatment, over 100,000 residents were potentially exposed to high levels of lead in the drinking water . After a pair of scientific studies proved lead contamination was present in the water supply, a federal state of emergency was declared in January 2016 and Flint residents were instructed to use only bottled or filtered water for drinking, cooking, cleaning, and bathing . As of early 2017, the water quality had returned to acceptable levels; however, residents were instructed to continue to use bottled or filtered water until all the lead pipes have been replaced, which is expected to be completed no sooner than 2020 . </P> <P> The Flint drinking water contamination issue started in April 2014 when Flint changed its water source from treated Detroit Water and Sewerage Department water (sourced from Lake Huron and the Detroit River) to the Flint River . Officials failed to apply corrosion inhibitors to the water . As a result, there was a series of problems that culminated with lead contamination, creating a serious public health danger . The Flint River water that was treated improperly caused lead from aging pipes to leach into the water supply, leading to extremely elevated levels of the heavy metal neurotoxin . In Flint, between 6,000 and 12,000 children have been exposed to drinking water with high levels of lead and they may experience a range of serious health problems . Due to the change in water source, the percentage of Flint children with elevated blood - lead levels may have risen from about 2.5% in 2013 to as much as 5% in 2015 . The water change is also a possible cause of an outbreak of Legionnaires' disease in the county that has killed 10 people and affected another 77 . </P>

When did flint michigan's water become contaminated