It might sound impossible… but in 1969, one of Niagara Falls was turned off.
Not slowed down. Not frozen.
Completely stopped.
Over time, rock from the cliff behind the American Falls had been breaking away and piling up at the base.
This pile of rock, called talus, had grown so large that it was changing the look of the Falls. In some areas, it had reduced the drop from about 100 feet to less than half that height.
There was a serious question:
Should the rocks be removed to restore the Falls to its original appearance?
To answer that, the United States Army Corps of Engineers was brought in to study the situation.
To investigate, they needed to shut off the water flowing over the American Falls.
So they built a massive temporary dam, called a cofferdam, stretching from the mainland to Goat Island.
In just a few days, thousands of tons of rock and earth were used to block the river and divert the water toward the Canadian side, increasing the flow over the Horseshoe Falls.
By June 1969, the American Falls ran dry.
For the first time in modern history, the rock face was fully exposed.
With the water gone, engineers were able to closely examine the cliff and the massive pile of rock below.
They discovered:
And there were other, more unexpected discoveries as well.
At the base of the Falls, decades of dropped and washed-in items had collected, including coins, debris, and personal belongings that had made their way over the edge.
Among those findings were two human skeletons, believed to be individuals who had gone over the Falls years earlier.
In short, the Falls were doing exactly what waterfalls naturally do... slowly changing over time, while quietly holding onto pieces of the past.
After studying the site, the International Joint Commission made the final decision.
Yes, the rocks could be removed.
But they chose not to.
Why?
Because removing the talus would mean artificially maintaining the Falls forever, constantly interfering with a natural process.
Instead, they decided Niagara should be left to evolve on its own.
In November 1969, the cofferdam was removed.
Water returned to the American Falls, flowing over the same rock formations you see today.
Niagara Falls might look permanent, but it’s always in motion.
Rock falls, erosion, shifting water, it’s all part of what makes this place what it is.
And sometimes, the best decision is to leave it alone.
Some of the most surprising moments in Niagara’s history come from attempts to control it. But time and again, nature has the final say.
See how these stories become part of the experience when you visit Niagara Falls on our tour.
Best Niagara Falls tour in Canada for 20 years.
