How much does Niagara Falls erode each year ?

Studies to determine how much erosion was taking place were started in 1842. Between that year and 1905 erosion took place at the rate of 1.16 meters, or 3.8 feet per year, at Horseshoe Falls. Between 1906 and 1927 the erosion rate declined to .70 meters, or 2.3 feet per year. The decline was due to water being diverted for hydro electric generation. Currently remedial efforts are underway to reduce the erosion even more. It is estimated that erosion is reduced to less than 1 foot per year due to those efforts. At American Falls the flow rate of 10,000 cubic feet per second is insufficient to cause any major erosion. As it stands today, American Falls has an erosion rate of about 3 to 4 inches per year. The biggest factor for the American falls is the fact that it has cracks at the Crestline in the top cap rock layer. Underneath that is a softer shale layer. The lifting action of water coming through these cracks cause them to become larger and along with the freezing and thawing ...  more

Accurate surveys of erosion of the Falls of Niagara began in 1842. From 1842 to 1905, the average rate of erosion of the Horseshoe Falls was 1.16 meters (3.8 feet) per year. From 1906 to 1927, this rate of erosion was reduced to .70 meters (2.3 feet) per year. This reduction coincided with the large quantity of water being diverted for hydro-electric generation. Today, through increased water diversion and anti-erosion remedial steps, the rate of recession at the Horseshoe Falls has been reduced to a fraction of what it used to be. Today it is estimated that erosion of the Horseshoe Falls is less than one foot per year. In the future, through remedial efforts and further water diversion that the amount of erosion at the Horseshoe Falls has been projected to be reduced to approximately 1 foot every 10 years. Remedial work has included: 1) In 1906, approximately 122 meters (400 feet) of crestline of the Horseshoe Falls at the Table Rock was filled in to ensure a more even flow of water ...  more