Monthly data, not seasonally adjusted
Lock delay is the extra time that commercial traffic spends moving through the nation's inland waterways. This delay is most often the result of high volumes at transit points, as well as occasional failures in equipment. This results in increased operating costs.
For reporting rivers, inland commercial traffic in 2011 spent 231,815 hours in lockage and 221,674 hours delayed, waiting for lockage. The greatest total delay in 2011 was at the Markland Lock on the Ohio River with 52,032 hours.
Monthly data, 12-month centered moving average
A moving average facilitates analysis of trends in highly variable data series.
|Commercial Vessel and Tow Delay||Mar-11||Mar-12|
|Total Ohio River System Hours of Delay||5,027||5,844|
|Percent change from same month previous year||-8.6||16.3|
|Total Upper Mississippi River System Hours of Delay||2,517||9,947|
|Percent change from same month previous year||151.6||295.2|
|Total Other Waterway Systems Hours of Delay||920||1,443|
|Percent change from same month previous year||-49.4||56.9|
NOTES: Data for the Upper Mississippi River System includes the Mississippi (north of the Ohio confluence), Illinois, Chicago, and Kaskaskia Rivers. Data for the Ohio River System includes the Ohio, Cumberland, Green, Barren, Kanawha, Allegheny, and Monongahela Rivers. Other rivers for which data are available are the Arkansas River, which has a confluence with the Mississippi below the Ohio, and the Tennessee and Clinch Rivers, which ultimately flow into the Ohio, but also feed traffic to the Tennessee-Tombigbee Waterway.
SOURCE: U.S. Army Corps of Engineers, Navigation Information Connection, Operations and Maintenance of Navigation Installations Report 10W, available at http://www2.mvr.usace.army.mil/nic2/default.cfm as of August 2012.