Why is the water so blue at Niagara Falls?

The river cuts through sandstones, limestones and some dolostones. But the culprit for the beautiful blue is the limestone! Limestone is composed primarily of calcium carbonate (CaCO3) and is white in color. As the river breaks down this rock into tiny crystals, these crystals will get mixed up into the water.



The stunning blue-green color of the water at Niagara Falls is a result of the immense power of erosion and the specific mineral composition of the Great Lakes basin. As the massive volume of water flows from Lake Erie toward Lake Ontario, it carries a high concentration of "rock flour," which consists of finely ground particles of limestone, shale, and sandstone. When sunlight hits the water, these suspended minerals absorb most of the spectrum but scatter the blue and green wavelengths back to our eyes. Additionally, the sheer depth and speed of the water contribute to its clarity and hue. It is estimated that 60 tons of dissolved minerals are swept over the falls every minute. This natural phenomenon is most vibrant during the spring and summer months when the flow is at its peak. In 2026, visitors can still observe that the water is notably clearer and "bluer" than many other large river systems, as the Great Lakes act as giant settling basins that trap heavier sediments before the water reaches the Niagara River.

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An estimated 60 tons of dissolved minerals are swept over Niagara Falls every minute. The colour comes from the dissolved salts and “rock flour”, very finely ground rock, picked up primarily from the limestone bed but probably also from the shales and sandstones under the limestone cap at the Falls.

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On August 18th 1954, teenagers, Ted Mercier, Joseph Hawryluk and Graham Scott swam across the Niagara River from the Canadian shore near Seneca Street to the American shore approximately 400 yards (the length of 4 football fields) downstream.

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The verdant green color of the water flowing over Niagara Falls is a byproduct of the estimated 60 tonnes/minute of dissolved salts and rock flour (very finely ground rock) generated by the erosive force of the Niagara River.

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From trophy trout and salmon to smallmouth bass and walleye, every species of fish that swims in the Great Lakes can be found in the waters around Niagara Falls USA. Book a charter, find a scenic stretch of shore or sign up for a derby — you're sure to find your own perfect watering hole.

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Niagara Falls Facts The sound of the Falls has been described as thunder, and is caused by air bubbles breaking as they are slammed up and out of the water. The plunge pool beneath the falls is 35m(100 feet) deep. It is estimated that Niagara Falls erodes at the rate of 1foot per year.

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Below the Chippawa-Grass Island Pool control structure, the river falls 15 metres (50 ft.) to the brink of the falls. The deepest section in the Niagara River is just below the falls. It is so deep that it equals the height of the falls above: 52 metres (170 ft.)

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The fresh water that plunges over Niagara takes around 685,000 gallons (2.6 million litres) of water from four great lakes: Lake Superior, Lake Michigan Lake Huron and Lake Erie - in fact, ? of the world's fresh water is found in these four great lakes.

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Preferred Region. The majesty that is Niagara Falls has had its, well, less majestic moments over the past two centuries. In fact, twice the falls have dried up completely – once stopped by nature and the second time 120 years later, it was stopped by man.

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In Niagara Falls, the source of our drinking water is located in the area of the Welland River at the Niagara River in the Village of Chippawa.

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But no feat has attracted more visitors than a scientific survey conducted in 1969. That year, the U.S. Army Corps of Engineers turned off American Falls. The engineers wanted to find a way to remove the unseemly boulders that had piled up at its base since 1931, cutting the height of the falls in half.

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Under an international treaty, the flow of water over Niagara Falls is reduced during the night to allow more of the water to flow into intakes used for power generation. This plan ensures that the Falls' natural beauty remains unaffected during prime viewing hours.

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Back in 1969, the Falls were “turned off.” Here's why and how it happened. Niagara Falls thrills visitors with a constant flow of wonder, but have you ever imagined a time when the Falls were not technically … the Falls?

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An area 12,300 years in the making, Niagara Falls is a natural wonder unlike any other. The history of Niagara Falls goes back thousands of years, to the Ice Age, when large torrents of water were released from the melting ice, draining into what is now known as the Niagara River.

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Niagara Gorge - Devil's Hole/ Whirlpool Rapids Loop (NY) The Niagara River Gorge is a 300-foot deep, 7-mile long chasm cut out of the Niagara Escarpment along the US-Canada Border downstream of Niagara Falls itself.

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Angel Falls, Venezuela Beginning with the one that is the tallest uninterrupted waterfall, at the height of 3,200 feet, Angel Falls is the largest waterfall in the world.

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People do not recommend swimming in the Niagara River, nor is it allowed in most areas. The river has strong currents, turbulent rapids, and unpredictable undertows, especially in the Lower Niagara River below Niagara Falls.

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Some of the more common species that inhabit the area are cardinals, robins, wood peckers, blue jays, herons, wrens, finches, thrushes, gulls, Canada geese, and chickadees. The chickadee and cardinal stay in the area year round.

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It's estimated that 90% of the fish that go over Niagara Falls, survive. Still, being stunned from the fall may leave the fish open to predation from the various birds that make the Niagara Gorge below the falls their hunting grounds.

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