The history of the Niagara Falls goes all the way back to the end of the Ice Age. About 12,000 years ago, water cascaded from newly melted ice, forming what we know as the Niagara Falls. 12,000 years old is relatively young compared to other waterfalls, some dating back to 2.5 million years old.
In what is now Lewiston, New York, the water spilled over the edge of the Niagara Escarpment. The force of the water wore away the rock layers, moving the falls upstream, where it met its present location. Today, the Falls have a striking green color because of the erosive power of water. The color comes from dissolved salts and “rock flour.” Rock flour is a finely powdered rock formed by glacial or other erosion. Sixty tons of dissolved minerals are swept over Niagara Falls every minute.
The 685,000 gallons of water that come down from the Niagara Falls do not come from thin air. It comes from four great lakes: Lake Superior, Lake Michigan, Lake Huron, and Lake Erie. These four great lakes also hold a fifth of the world’s fresh water. The water travels over the Falls when it travels from the Niagara River and then to Lake Ontario before traveling downstream to the St. Lawrence River, and then finally it reaches the Atlantic Ocean.
The Falls are continually forming. The Niagara River's yearly cycle of freezing and thawing, together with gradual erosion and periodic rock falls, all contribute to its continual formation. During peak tourist hours, more than 168,000 cubic meters of water
flow over the crestline of the Falls every minute. The Falls may be the fastest moving waterfall and has moved back
seven miles in the last 12,000 years. The
first persons to see the might of Niagara Falls were likely local Native Americans. The City of Niagara was the birthplace of hydroelectric power. Hydroelectricity is the process of producing electricity by harnessing the gravitational force of falling or flowing water. The water from the falls is used for a wide range of reasons including hydroelectricity, drinking, boating, swimming, and fishing. More than one million people of the Canadian and United States population use the waters of the Niagara Rivers.
The flow from Lake Erie into the Niagara River can change depending on whether there is high or low precipitation throughout the year. The International Joint Commission (the USA and Canada) have been controlling the levels since 1910. With nearly 18% of the world's fresh water supply, the Great Lakes are the most extensive surface freshwater system in the world. The falls are estimated to disappear in 10,000 years when the water reaches Lake Erie.