Does Niagara Falls freeze in Winter?
The Niagara River handles 212,000 cubic feet of water per second. The average depth is approximately 16 feet with a flow rate of 4 to 8 miles per hour. The Niagara River does not freeze over. The Falls of Niagara and the river below the Falls does not freeze either. The volume of water going over the Falls, the depth and speed of the water below the Falls also precludes freezing. The water will not be stopped or frozen solid.
The ice bridge however does form at the base of Falls and over portions of the Niagara River below the Falls. The ice bridge is formed in late December to the end of February and into mid March dependant on the weather.
Lake Erie which drains into the Niagara River is a large lake but rather shallow. By the end of December, the entire lake surface is frozen over. Although an ice boom has been put into place since the 1960′s at the mouth of the Niagara River and Lake Erie. The boom holds back most of the ice but not all. When the ice goes over the Falls in volume the ice freezes to the edges of the gorge and builds upon itself until the river is covered in this giant layer of ice. This layer has grown to eighty feet thick in the past and currently 40 feet is not uncommon.
The Falls of Niagara still flows as does the water under the ice and the ice shelf seems to rise on layer of air that builds under the ice surface.
The American Falls have frozen over on six occasions since the keeping of records began. Each were attributed to ice jams that have actually curtailed the flow of the American Falls to mere trickles.
Unlike the Horseshoe Falls (which has never frozen over), the American Falls are susceptible to freezing because of the small amount of water flow. Normally the American Falls has a peak mean flow of 10,000 cubic feet of water per second. The winter mean water flow is reduced to less than 8,000 cubic feet of water per second. This minimal flow is barely sufficient to cover the rock face of the Falls. During harsh winters, ice frequently built up at eastern end of Goat Island causing an ice dam to reduce the water flow to the northern channel which feeds water to the American Falls. As a result water flow is restricted sufficiently that any remaining waters quickly freeze over.
The installation of the ice boom at the mouth of Lake Erie, the building of the International water control dam (which regulates water flow) and milder winters have all but eliminated the possibility of the American Falls ever completely freezing over in modern times.
The American Falls water flow was reduced to such an extent in 1909, 1936, 1938 and 1949 that it froze over.
On February 7th 1936, as a result of an ice jam at the eastern end of Goat Island the American Falls froze completely. The flow started to freeze on January 27th. The American Falls remained frozen for a period of 15 days before the ice dam upriver broke apart and returned the flow of water of the Falls to normal.
The American Falls today receives only 10% of the total water flow. In the early 1900′s that flow was much less, perhaps only 5%. The low level of water flow was amplified because of the beginning of water diversion for hydro generation and the lack of a method to divert water towards the American shoreline. The riverbed above the Falls slopes towards the Canadian shore.
Long before the ice boom was utilized at the mouth of Lake Erie to hold back the lake ice, all the ice flowed through the Niagara River. The amount of ice flowing into the river depended upon winds blowing over the lake. West & south-west winds brought more ice flow into the river while east winds would lessen the amount.
The April 1909 ice flow was sufficient to dam off the flow of water at the eastern end of Goat Island. What water was left (a mere trickle) quickly froze. People were able to walk on the river bed just above the American Falls where there was normally water. It wasn’t until the ice jam shifted and broke apart, that the water flow was returned to normal.
A second similar ice jam occurred in January of 1938. The ice jam was so substantial that it too cut off the main flow of water to the American Falls. Again the American Falls was reduced to a trickle and quickly froze. More importantly, it was this ice flow that caused the collapse of the Upper Steel Arch Bridge (Honeymoon Bridge).
People are not allowed on the ice bridge.
The ice shelf is constantly growing, shifting and breaking up. In most winters the ice bridge can build and suddenly break up several times.
In 1997, the ice bridge was bigger than usual because several sections of the ice boom were knocked out in early winter during a storm.
The enormous amount of mist generated from the falling water creates a picturesque sight as it freezes on contact against anything it falls upon along the shoreline creating a crystallized winter wonderland.
Do the Falls Freeze over in the Winter?
Yes and No…… We’ll try to explain
The tremendous volume of water never stops flowing, However, the falling
water and mist create ice formations along the banks of the falls and river.
This can result in mounds of ice as thick as fifty feet. If the Winter is cold for long enough, the ice will completely stretch across the river and form what is known as the “ice bridge”. This ice bridge can extend for several miles down river until it reaches the area known as the lower rapids.
Until 1912,visitors were allowed to actually walk out on the ice bridge and
view the Falls from below. February 24th of 1888 the local newspaper
reported that at least 20,000 people watched or tobogganed on the ice.
Shanties selling liquor, photographs and curiosities abounded. On February
4th 1912 the ice bridge broke up and three tourists lives were lost.
There can also be a great deal of “mini-icebergs” which flow down the
Niagara River from frozen Lake Erie. The flow of ice has been reduced
considerably by the yearly installation of the “ice-boom” on Lake Erie. The
ice-boom is a long floating chain (2miles- 3.2 KM) of steel floats strung across the Niagara River from Buffalo New York to Fort Erie Ontario.
It is set in place during the month of December and removed during the
month of March or April. It is maintained by the New York State Power
Authority. The ice boom helps prevent the ice from clogging the river and most importantly the hydroelectric companies water intakes.
HOWEVER…. The flow of water was stopped completely over both falls
on March 29th 1848 due to an ice jam in the upper river for several hours. This is the only known time to have occurred. The Falls did not actually freeze over, but the flow was stopped to the point where people actually walked out and recovered artifacts from the riverbed!