What is the significance of stack date and why is it important..??
Also known as Cut-off time, Vessel cut-off, Gate cut-off etc, the term STACK DATE has a massive significance in the loading of an export or empty container on board a ship and is a crucial element in the whole port operation..
For the sake of simplicity I will refer to it as stack date or stack period throughout this article..
Stack dates (stack opening and stack closing dates – also known as stack period) are set by the port or container terminal in conjunction with the vessel operator based on the ETA of the ship at a port..
Depending on the port, terminal and country, stack dates maybe nominated as Provisional initially (sometimes as early as 2 weeks prior to the ETA (Expected Time of Arrival) of a ship)..
Once a steady ETA of the ship has been declared by the shipping line (this maybe possible when the ship is say 4 days away from the port), the stack date may then be nominated as Firm..
The stack period may normally be between 3-5 days again depending on the port, terminal and country.. There is no fixed rule on this..
An example of the stack period with both Provisional and Firm stacks is shown from Durban Container Terminal which also incorporates City Deep (Inland Port)..
The stack period maybe announced by the shipping line or the customer may get this information from the ports system or notices..
Based on these stack dates, the shipper and/or his agent must make all efforts to bring their full export containers into port within the stack period..
If the shipping lines are loading any empty containers that also must be brought into the port within the stack period..
But why is a stack period required..??
Imagine the current mega ships that are capable of carrying more than 20,000 TEUs..
Let us assume that at one port, the shipping line has 6,900 containers to be loaded on a ship..
Now imagine the line’s container stowage planner who needs to do the stowage planning and allocate stow positions for these 6,900 containers on board the ship.. (For further info on stowage planning, please read my previous article Container Stowage Planning and how it works)..
Also imagine the yard planner who needs to be in a position to feed these 6,900 containers to the ship in good time so the ship does not idle at the berth..
Now finally imagine what would happen to the yard planner and the ship if these 6,900 containers all arrive at different times at the port including while the ship is working..!!!!!
THERE WILL BE TOTAL CHAOS leading to short shipped boxes, ship delays, schedule not being met, container shut out and general mayhem..
The main reason that a stack period is implemented is so that there is enough time
- for the transporters to bring the containers to be loaded on the into the port,
- for the exporters and their agents to do the shipping documentation in time,
- for the ship planners to plan the ship effectively,
- for the yard planners to plan their feeding properly and ensure all containers are present
so that when the ship arrives, the loading operations may comment without undue delay..
Once again, depending on the port, terminal, shipping line, number of containers to be loaded etc, the stacks could close 2-3 days before the berthing of the ship or later, depending on the circumstances..
So what happens if the containers are not in the stack within the stack period..??
If the containers are not in stack within the stack period, the port may not allow the containers to be brought into the terminal for that particular ship..
The reason is that if there any extensions to the stack period it could interfere with the feeding of the containers to the ship and the loading plan which could result in ship delays..
Although it is possible that the port authority may make an exception and allow later arrivals, if there are a lot of such containers, these extensions can cause delays to the working of the ship which in turn will affect the customer’s documentation and also affect other ships that are waiting for that berth at the port..
So it is in everyone’s interest that the stack dates are monitored and followed to ensure that the boxes reach the stacks in time and are loaded..
It is normal for ICDs (Inland Container Depots) to have their own stack period in order to cater for the boxes that need to be railed from the ICD to the sea port..
What is the practice in your port with regards to stack date and what is it called..?? Does it work as mentioned above..??
Article has been updated and republished..