Funding and Managing the U.S. Inland Waterways System: What Policy Makers Need to Know: What Policy Makers Need to Know (2015)
Chapter: Appendix F Summary of Correlations Between Lock Performance and Lock Age (in 2014) Calculated from the Date of Known Major Rehabilitation Construction
| River System | Average Age of Lock Installations (years) | Correlation with Effective Age of Locks on a River System | |||||||
| Lockages | Vessels Delayed (%) | Tows Delayed (%) | Average Vessel Delay | Average Tow Delay | Average Closure Duration | Closure Frequency | |||
| All installations | 61.04 | 0.2184 | 0.1404 | -0.0750 | 0.1321 | -0.1226 | 0.1691 | 0.2254 | |
| Ohio River | 35.45 | -0.0076 | -0.0957 | -0.0959 | 0.1081 | 0.0400 | 0.2407 | -0.0477 | |
| Mississippi River | 24.86 | -0.3019 | 0.1758 | -0.0103 | -0.2738 | -0.0463 | 0.6458 | 0.1295 | |
| Illinois River | 22.28 | -0.5754 | 0.0357 | -0.2425 | -0.3880 | -0.2560 | -0.6243 | -0.5700 | |
| Columbia–Snake Rivers | 44.88 | -0.1953 | 0.1088 | 0.1566 | 0.0851 | 0.0677 | 0.8220 | 0.4676 | |
| Gulf Intracoastal Waterway | 71.80 | 0.1603 | 0.1273 | 0.1050 | -0.1422 | -0.1403 | 0.2972 | -0.1875 | |
| Arkansas River | 45.33 | 0.4568 | -0.7410 | -0.7359 | -0.7123 | 0.4552 | -0.2562 | -0.1563 | |
| Black Warrior, Tennessee, Tennessee–Tombigbee, Tombigbee | 61.04 | 0.3474 | 0.5655 | 0.7040 | 0.3585 | -0.1630 | -0.1735 | 0.7485 | |
| Monongahela River | 56.67 | 0.5545 | 0.7521 | 0.8632 | 0.5526 | 0.3800 | Gaps in data | 0.6358 | |
| Allegheny River | 61.75 | -0.0454 | 0.3048 | -0.0426 | 0.1435 | -0.1276 | Gaps in data | 0.0612 | |
NOTE: High positive correlation (dark blue shading), greater than 75 percent correlation; high negative correlation (dark pink shading), less than -75 percent correlation; medium positive correlation (light blue shading), between 50 and 75 percent correlation; low correlation (white), within ±50 percent correlation. Some rivers indicate negative correlations with lock age because the correlations are affected by traffic level and rehabilitation; that is, some of the older locks have less traffic and so fewer traffic-related problems, or they may be rehabilitated and so experience fewer closures and delays.
SOURCE: U.S. Army Corps of Engineers Lock Use, Performance, and Characteristics, http://www.navigationdatacenter.us/lpms/lpms.htm, Locks by Waterway, Tons Locked by Commodity Group, Calendar Years 1993–2013; Locks by Waterway, Lock Usage, Calendar Years 1993–2013; and Locks by Waterway, Locks Unavailability, Calendar Years 1993–2013. Accessed July 2014.
