What significant event highlighted issues with water quality in Flint, Michigan?

The Flint Water Crisis is the significant event that brought national attention to serious issues with water quality in Flint, Michigan. This crisis began in 2014 when the city's water source was switched to the Flint River without adequate treatment to prevent lead leaching from aging pipes. As a result, residents were exposed to high levels of lead in drinking water, leading to extensive public health concerns, reports of illnesses, and a public outcry for government accountability. The crisis highlighted the importance of sustainable water management practices, infrastructure maintenance, and the need for stringent water quality standards to protect public health. This event serves as a critical example of how governmental decisions can directly impact community health and safety. Other events listed in the options, such as oil spills or river fires, while significant, do not relate specifically to the water quality issues faced by the residents of Flint.