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CHAPTER 9 Marine Terminal Container Yard Congestion Container Yard Congestion Impacts The impact of congestion at marine terminals can be seen in the relationship between volume and turn times in Figure 91. Although the general relationship is clear, the specifics will vary by terminal. In the examples, the first terminal is relatively unaffected by volumes of up to 1,100 per day while the second shows marked increases in turn times for volumes above that level. Congestion also results from disruptions to marine terminal operations. Such disruptions have resulted from work stoppages, labor shortages, changes in ocean carrier calls, and rail service shortfalls. A short-lived event such as a systems problem will lead to congestion while the terminal gets back to normal. More extended problems such as changes to vessel, carrier, or alliance termi- nal assignments may result in congestion for weeks or months as the terminal, the customers, and the drayage firms adapt. Errors or disruptions within the CY are generally not documented in terminal operating sys- tems, seldom result in trouble tickets, and most incidents by themselves are not serious, yet can be a major source of cumulative delay. The research team learned of a wide variety of potential problems, including the following: Drivers and tractors getting out of order in lines waiting to receive containers in the stacks, Lift equipment malfunctions, Errors in communication between the gantry crane operator and driver, Drivers pulling the wrong container in wheeled terminals, Lift equipment transferring the wrong container in stacked terminals, High wind conditions that can slow or interfere with lift equipment operations, Inexperienced drivers going to the wrong pickup point or being unaware of procedures, Retrieving containers that require excessive rehandling due to their position in the stack, Labor shift changes, Redirection of assets from yard operations to ship operations, Traffic jams that can occur because too many trucks are in the terminal at a given time, and Specific lane blockages from trucks queuing behind a specific crane. All of these delays are considered a normal part of terminal operations and are not typically seen as the first areas that require specific intervention. Nevertheless, terminals do have some ability to reduce the probability of routine CY delays. For example, ports can institute driver education efforts that include a notification system for changes in terminal procedure. Better coordination between gate operators and lift operators can ensure that the CY does not become excessively crowded. Furthermore, solid redundancy procedures to handle excessive demand for a particular gantry crane can help to prevent localized gridlock from occurring within the terminal. 71