when did flint michigan's water become contaminated
Flint water crisis 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.
Great Lakes In 2009, the lakes contained 84% of the surface freshwater of North America;[40] if the water were evenly distributed over the entire continent's land area, it would reach a depth of 1.5 meters (5 feet).[15] The source of water levels in the lakes is tied to what was left by melting glaciers when the lakes took their present form. Annually, only about 1% is "new" water originating from rivers, precipitation, and groundwater springs that drain into the lakes. Historically, evaporation has been balanced by drainage, making the level of the lakes constant.[15] While the lake levels have been preserved, intensive human population growth only began in the region in the 20th century and continues today.[15] At least two human water use activities have been identified as having the potential to affect the lakes' levels: diversion (the transfer of water to other watersheds) and consumption (substantially done today by the use of lake water to power and cool electric generation plants, resulting in evaporation).[41]