The Berth Allocation Problem with Channel Restrictions

Shipping channels are often a constraint to port capacity because of the significant capital cost and environmental impact of channel dredging. Channels are often narrow in places, which constrains the capability of vessels passing in opposing directions. Capacity impacts of channel operations are significant in tidally restricted ports, where deep draft vessels are able to move through the channel only during narrow windows around high tide to maintain sufficient under-keel clearance. There has been much research to date around berth allocation and sequencing, but in channel-constrained ports, the value of these existing approaches can be limited. This is particularly apparent in a numerical example presented in this paper where the berth allocations are suboptimal when the channel is not considered. In this paper, we present an approach to optimize the scheduling of channel movements and, furthermore, to integrate the channel scheduling and berth allocation/sequencing problems. A mixed integer program formulation is presented for this problem, based on a no-wait bidirectional flow shop with parallel machines. Benchmark problems consistent with the literature for berth allocation/sequencing have been modified to incorporate a range of channel configurations and used as test cases for the proposed model.