It's typically removed when the weather warms up enough, the boom is to prevent ice from going into Niagara River
If the weather cooperates, the New York Power Authority and Ontario Power Generating will begin the process of removing the ice boom on the Niagara River today.
Each winter, since 1964, the boom has been placed near the outlet of Lake Erie, to prevent ice flow into the river. That ice has the potential to jam up, possibly causing damage to the shoreline and reducing water flow for the hydro-electric station.
As of yesterday, the water temperature near the ice boom was just above freezing.
This would be the earliest the boom has been moved, the previous earliest date was February 28th, 2012.
The latest date to remove it was May 3, 1971.