Characterizing Longitudinal Vessel Arrival and Queue Behavior from AIS at the Port of Houston

We present the methods and results for automatic identification system (AIS) vessel tracking data analysis to support port operations and simulation efforts in the Houston region. While AIS data have been widely used to measure port performance, we specifically study the validity of assuming a Poisson arrival process for the Houston anchorage and quantify observed anchorage waiting behavior for container, noncontainer cargo, and tanker vessels in a longitudinal analysis from 2019 to 2024. Statistical testing and graphical analysis are used to examine the interarrival times. We contend that the Poisson assumption is likely valid for container and noncontainer cargo vessel types, but less clear for tanker vessels. The queue analysis shows that the Houston anchorage is dominated by tanker vessels, of which a majority experience waiting, and that deviations in container vessel queue size and duration were observed in late 2021 and 2022, corresponding to the global demand surge for container cargo. These findings directly support simulation studies for the Port of Houston and provide empirical evidence of long-term vessel arrival and waiting behaviors in the Houston anchorage.