Years of prioritising cost efficiency over operational resilience have left container shipping increasingly exposed to port congestion, according to a new report from UK consultancy Drewry.

Drewry said global average vessel waiting times during the first seven months of 2026 were nearly double those recorded in the corresponding period of 2019. Average time spent in port rose by 31%, with a growing proportion of port calls now taken up by vessels waiting for a berth rather than undergoing cargo operations alongside.

The findings come as worldwide congestion reaches record levels. More than 4.3m teu of containership capacity is currently waiting to berth, exceeding the absolute peak recorded during the Covid-era disruption.

One factor is the rise of “burst congestion”, in which delayed vessels arrive in clusters and create short-term demand that overwhelms terminals, even where infrastructure is adequate during normal operating conditions. The World Bank also highlighted this pattern in its latest Container Port Performance Index.

Drewry’s analysis indicates that high berth utilisation significantly extends recovery times. A terminal operating at 90% berth utilisation can require about one week to recover from a single day of disruption. At 75% utilisation, the corresponding recovery period is approximately two days.

Maersk chief executive Vincent Clerc recently linked congestion in Europe, the east coast of South America, West Africa and the Middle East to insufficient investment in terminal capacity over roughly 15 years following the global financial crisis. He said investment had lagged while trade volumes and imbalances increased.

Jan Hoffmann, the World Bank’s ports lead, has similarly warned that investment may fail to keep pace with demand, particularly as uncertainty leads investors to seek higher returns before committing capital.

Drewry said the causes are more complex than investment levels alone. Across nine major container ports, capacity increased by 21% between 2019 and 2026, compared with a 28% rise in volumes. Terminal operators have also raised utilisation to improve returns, reducing the spare capacity available when disruption occurs.

Carrier scheduling practices can add to the pressure. Blank sailings, extra loaders and ad hoc voyages may produce sudden peaks in terminal demand, contributing to the clustering of vessel arrivals.

Durban illustrates how congestion can spread across port operations. Vessel waiting times there currently range from eight to 12 days, while some carriers have warned that delays could extend to 20 days as disruption affects berths, yards and landside activities.

Drewry concluded that terminal operators cannot independently fund large amounts of unused buffer capacity. The consultancy said the container shipping ecosystem remains structured around cost optimisation rather than resilience.