TABLE 2-3-8 St. Lawrence Seaway U.S. Locks Downtime by Cause: 1995–2007
Hours of downtime, unless otherwise noted
Total Weather System
Weather Vessel All other downtime (percentage availability
related incident causes hours of total) (percentage)
1995 88.5 32.6 16.7 137.8 64.2 99.0
1996 143.4 38.3 5.9 187.6 76.4 97.0
1997 65.2 31.2 35.6 132.0 49.4 98.0
1998 43.2 43.3 12.1 98.6 43.8 98.5
1999 2.0 46.3 1.3 49.6 4.0 99.2
2000 53.7 27.8 2.6 84.1 63.9 98.7
2001 56.8 45.1 8.9 110.8 51.3 98.3
2002 41.1 16.9 5.1 63.1 65.1 99.1
2003 57.6 15.9 0.0 73.5 78.4 98.9
2004 43.8 15.0 7.2 66.0 66.4 99.0
2005 16.9 12.1 6.0 35.0 48.3 99.5
2006 19.1 34.5 8.8 62.4 30.6 99.1
2007 39.7 23.6 10.4 73.7 53.9 98.9
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, typicaly from late December to late March.
SOURCES: 1995–2001: U.S. Department of Transportation, Saint Lawrence Seaway Development
Corp. (SLSDC), Annual Reports (Washington, DC: Various years), available at http://www.greatlakes-
seaway.com. 2002–2007: SLSDC, personal communication, as of August 2008.