Not during peak tourism months
As the hydroelectric stations became even more advanced, the falls became even less spectacular. Using water turbines reduces the waterflow rate, which reduces the magnificence of the waterfalls. Engineers realized what they were doing and devised a plan that would benefit everyone.
The power plants struck a deal with the tourism industry of Niagara Falls. In the contract, the power plants would carry out its business while tourism slowed down. In the peak seasons, the plants would either limit their energy production or seize operations altogether. Plus, there would always be a surplus of electricity to cover several months of reduced productivity.