When wolves made their comeback, they actually changed rivers. They killed deer, lessening the amount of deer, which may I mentioned, was overpopulated. This brought back more trees, which led to bears and many other animals to come back into a higher population which then led to other animals with low numbers to come back into population. This chain reaction continued which eventually caused the rivers to meander less and more pools were formed due to erosion.
In 2013, Flint officials discussed changing their water source to save money. In 2014, they switched, even though the source was NOT ready. Within weeks, people began to witness changes in the water. It was discolored, and not to mention it smelled foul. This water had high levels of molecules that were very similar to methane. Many people got sick, and 15 people died from the Flint Water Crisis.