At each port, the Port Authority is responsible for the maintenance and development of the port facilities and for maintaining navigable access to the port for commercial shipping. To proactively plan the operations, the Port Authority needs to initiate solutions to comply with the demands for e.g. depth or operability during approach and departure.

A potential and expensive deepening of the main navigational channel is regarded as one of several proactive planning initiatives that a modern port operator has to carry out on a regular basis in order to accommodate for the ever-increasing demands of the commercial shipping industry.

Joined forces

In collaboration with DHI, we have developed a new method to evaluate and quantify the approach and departure operability issues.

A study based on the probability of grounding can be used to increase the operability, i.e. an approach channel can be optimised with regard to dredged quantities and cost. Thereby optimising the operability.

Based on a panel model of a ship in a given loading condition we are able to calculate the theoretical motions of a ship in different sea states, which combined with statistical methods, enables the probability of grounding to be determined.

DHI use their MIKE by DHI software package to calculate current, tide and waves for a given period and a given location.

Based on our computations the DHI numerical channel optimisation software (NCOS) calculates the operability by checking passages of a route starting every ½ hour. The actual environmental condition is used to look up the grounding risk. An agreed risk level provides the program with a span to mark a passage as operational or too risky to enter. Finally, the program is able to provide estimates of the operational limitations for the channel.

Besides giving operational percentages, the method pinpoints the “high” risk areas and thereby optimises the approach channel not least as otherwise expensive dredging can be minimised.