Hours of downtime, unless otherwise noted
|Weather related||Vessel incident||All other causes||Total downtime hours||Weather (percentage of total)||System availability (percentage)|
NOTES: Weather-related causes include poor visibility, high wind, and ice. All other causes includes lock equipment malfunction, civil interference, pilotage, and water level/flow. These data pertain only to the two U.S. locks (Snell and Eisenhower) on the St. Lawrence Seaway between the Port of Montreal and Lake Ontario. Canada operates another five locks along this portion of the Seaway. In addition, Canada operates locks at the Welland Canal along the Seaway. System availability does not include the time when the locks are closed for the winter, typically from late December to late March.
SOURCES: 19982001: U.S. Department of Transportation, Saint Lawrence Seaway Development Corporation (SLSDC), Annual Reports (Washington, DC: Annual Issues), available at http://www.greatlakes-seaway.com. 20022008: SLSDC, personal communication, December 2009.