In 1969, the rushing water that is Niagara Falls came to a halt for several months. Looking at the Falls today, it’s hard to imagine a time when all of the water just stopped. But it did. One of the three falls, the American Falls, became little more than a trickle.
Why Did Niagara Falls Run Dry?
American Falls is well known for having a pile of rocks, or talus, at its base. This accumulation is caused by rock slides that have occurred over the years. In the 1960s, experts became concerned that additional rockslides would completely erode that portion of the Falls.
This fear is what prompted the American-Canadian commission to make the decision to dewater the American Falls for a whole five months. To do so, over 1,200 trucks worked to dump around 28,000 tons of rocky fill into a cofferdam upstream of the Falls. As a result, this diverted the flow of water toward the larger Horseshoe Falls.
This gave researchers a chance to study the composition of the falls and make a long-term plan moving forward. With no water in their way, the US Army Corps of Engineers was able to conduct an in-depth investigation on the matter.
Creepy fact: workers uncovered two corpses during their investigation!
Did Tourists Keep Coming?
Tourists kept coming, wanting to see what the Falls looked like with no water running down it. This also gave them the chance to collect a sea of coins that had been thrown into the water over the years. Meanwhile, engineers mapped and probed the stresses, faults and pressures of the rock.
What Did Workers & Engineers Do?
Special equipment was planted to track rock movements in a variety of locations, and steel bolts and cables were used to keep rocks stabilized around Luna Island and Bridal Veil Falls. In addition, drainage holes were placed to reduce hydrostatic pressure around the falls.
Engineers decided it was best to leave the mass of talus that had accumulated beneath the American Falls, as nature intended. While it would have been simple enough to remove it, it would have been a lot of work for a goal that would only serve an aesthetic purpose, while going against the grain of nature.
A few months after the waterfall went dry, the cofferdam was slowly removed, and water began pouring over the American Falls once again.
It’s likely that the Falls will run dry again at some point, perhaps giving you the chance to see what it looks like when no water free-falls over the edge. Rumor has it, two old bridges that hang above the Falls require replacement and in order to do so, engineers would likely need to dewater one or more of the waterfalls.
Will Niagara Falls Ever Really Dry Up?
It is estimated that the Falls formed around 12,000 years ago during the Pleistocene period. Over this time, the area has been under the pressure of constant erosion – one look at the powerful water gushing over the falls and it’s easy to understand why. With each passing year, this erosion causes the face of the cliff to break off and move slightly farther back. The exact rate of erosion will vary over time based on factors like how much water is going over the cliff, how high the drop off is, and what types of rocks make up the base of the waterfall.
Over the last 12,000 + years, Niagara Falls has moved around seven miles upstream. Given this rate of movement, it will be around 23,000 years before the falls disappear into Lake Erie. That’s plenty of time for you and all of your children and grandchildren to come enjoy the splendor that awaits at this incredible natural site.
Visit the Famous Falls!
Come visit Niagara Falls in all its splendor – and spend the night out in nature at our nearby campground. Learn more about our family-friendly accommodations at Campark