This was the prediction posited by the by the United States Engineering Corps. They believed that the constant rushing of the water was causing damage at the base of the cliff, making it unstable, and while they could deal with a very slow year on year retreat, they weren’t prepared for a large flood which would ensue if the cliff fell away in a large chunk. So they decided to perform a geological survey on the cliff face and perform any required maintenance work
But how does one work on a waterfall that is hurling 168,000 m3 of water over its top every minute?
The Army Corps of Engineering took the simplistic approach. The water was a problem – so they took away the water.
In an unprecedented move they de-watered the Niagara Falls, rerouting the water through a newly cut riverbed which allowed the water to rejoin the river further down. After this the cliff and several miles of river were left bone dry.
Over the course of the next six months they cleared away debris from the base of the cliff and drilled some holes into the cliff to maintain a constant moisture level. They also set up a walkway.
A mere 20 feet away from the cliff face it became a great site for the tourists who wandered across with perplexed looks. Especially when they were allowed to amble down the dried out river bed.
The dry times had to come to an end and after installing some hydroelectric turbines at its base the Engineers decided to blow up their temporary dam and allow the water to flow once more.
To this day the Niagara Falls gallantly gush water day by day by day. Nothing has since impeded their flow. In this case, the mission was a success.
However thousands of tourists never saw and never will see the splendour of a dry Niagara Falls, one of the few modern day wonders.