The Old Ice Boom
Since 1964, an ice boom has been stretched across the mouth of the Niagara River at Lake Erie. It has kept the ice build up in Lake Erie from flowing into the lower gorge of the Niagara River causing an ice bridge.
The old ice boom had been constructed of 30 foot (9.1m) floating timbers connected by steel cables. 22 span cables were used to connect each span section. Each span consisted of 13 timbers individually chained. Each span was anchored at the bottom at 400 foot (122m) intervals by using 2.5 inch (6.4cm) steel stay cables.
Current Ice Boom
In 1997, the modern ice boom was utilized for the first time.
The boom is made up of 22 span cables and each boom span consists of a series of 11 hollow steel surface floating pontoons. These are anchored to the river bed at 400 foot (122 meter) intervals by a 2½ inch (6.4 cm) diameter steel stay cables. Each pontoon is 30 inches (76 cm) in diameter and 30 feet (9m) long.
In 1999, the first 7 spans were reduced to 10 pontoons each. This was done to create a more equal spacing between the pontoons. It was believed the spacing would avoid collisions of multiple pontoons during rough weather, avoiding damage to the pontoons. The modern ice boom requires less maintenance, is more buoyant, and more efficient at restraining the ice pack.
The ice boom is flexible. It is designed to assist in the formation of a stable ice arch at the mouth of the Niagara River.
The ice boom will not stop all of the ice from flowing from Lake Erie into the Niagara River. During periods of storms or high winds, the ice arch breaks and the pressure on the ice boom becomes excessive. Then the boom pontoons will submerge to allow the ice to flow over it. When the pressure returns to normal, the boom pontoons return to the floating position again cutting off the ice flow.
The ice boom prevents excessive ice build up in the Niagara River, which prevents ice build up at the hydro-electric water intakes downstream. This has resulted in the reduction of hydro production in the years before the installation of the ice boom. It also reduces shoreline erosion and destruction to property along the shoreline of the Niagara River.
Lake Erie has an average depth of approximately 60 feet (18.2m) and will, during most winters, freeze over completely creating 10,000 square miles (25,900 sq. km) of ice. The Niagara River is only 23 square miles (60 sq. km) and could not handle such a large volume of ice.
With or without the ice boom, only 2% of all ice from Lake Erie enters the Niagara River. The remainder (98%) of the ice pack melts in Lake Erie.
The ice boom does not alter the time the ice will melt in Lake Erie. Studies have also shown that the ice boom has little effect on the daily weather in Buffalo, New York.
Each spring, the International Niagara Board of Control determines the date when the ice boom is removed. Their decision is based upon the amount of ice remaining in Lake Erie and the weather conditions at that time. Normally, the required date for the removal of ice boom is April 1st, unless there is still more than 250 square miles (650 square kilometres) of ice in the eastern portion of Lake Erie. The earliest removal of the ice boom occurred on March 5th 1998 and the latest removal of the ice boom occurred on April 25th 1997.
On January 28th 1938, an ice bridge caused the Falls View International Bridge, also known as the Honeymoon Bridge, to collapse.
On February 4th 1912, the Great Ice Bridge disaster occurred when the ice bridge suddenly broke apart carrying three persons to their deaths.