The tons of water that flowed over the Niagara Falls on the United States side along the U.
The tons of water that flowed over the Niagara Falls on the United States side along the U.S. - Canadian border were shut off on Thursday (12 June). It was accomplished by the building of a coffer dam up river in just four days.
The water was dammed to permit a study of the rock structure where the water spills over a high cliff so that ways could be flattened out and would finally disappear. The rocky debris at the foot of the falls will be hauled away as part of the cleaning process.
In the next few days a sprinkler system will be installed to keep the face of the falls wet so that the brittle rocks will not crack and add to the erosion problem. The falls will be kept this way until December when the dam holding back the river will be blown up. By that time the necessary work on the structure of the falls should be accomplished.