Port Congestion is the term commonly used to describe the situation where vessels have to queue up outside a port and are waiting for a spot so they can load or offload. Ports have a limited amount of dockage and in most cases capacity does not match demand. That is why vessels usually have to wait in the anchorage, before being able to access the port and use the cranes or the pier.
Now, an anchorage is a location at sea where anchors can be lowered. The purpose of securely resting a ship at sea can be for waiting to enter ports as well as for taking on cargo or passengers where insufficient port facilities exist. Such locations usually allow vessels to safely anchor in protection from bad weather conditions and other hazards as well.
So now, based on the time all vessels spent at the Port or the Anchorage, MarineTraffic can provide you with more information about each Port and its congestion in the form of two bar charts. After clicking on the Port Details page, simply scroll down to find the Port Congestion, currently on its beta version.
The bar chart illustrates the Median time that all vessels spent in the Anchorage or the Port each week of the year. The Median is the value separating the higher half of the records sorted by time from the lower half. The basic advantage of the median compared to the mean, which is often simply described as the average, is that it is not skewed so much by extremely large or small values, and so it's safe to assume that in this instance, it provides the most accurate value. This is useful in the calculation of Port Congestion as there are other reasons why a vessel might have remained at anchor, other than congestion, such as warm lay-up, authorities demands, etc.
The Port Congestion information is calculated per port, per week, for all commercial vessels. In order to calculate the time at port/anchorage, we consider all vessels that departed the previous week from the port, while having arrived in the port within the last 2 months. Similarly vessels maximum anchorage stay accounted for is in the last 5 months.
The default grey bar represents all vessels. If you click and drag your mouse within the chart, you will be able to select a more specific section to zoom in. Hovering your mouse over a bar gives you a summarized view of the information on the chart. To return to the previous state, click on the Reset Zoom button.
Now, if you are interested in getting information about a specific market, you will notice at the bottom of the chart a vast selection of options. You can either select the type you are interested in or choose more that one to create a comparison bar chart.
And that is not all the information you can get from this chart. If you are looking to go deeper than the market, you can click on any specific type and get a breakdown per Vessel Class. As before, hovering the mouse over the bar will give you an overview and clicking and dragging the mouse will zoom to a specific area. To return to the previous view, simply click on any bar of this chart.
Note: Look at the sub-heading text to get information on how to get more or return to the previous state.